The International Magazine on Banana and Plantain...INFOMUSA The International Magazine on Banana...

INFOMUSAINFOMUSAThe International Magazine on Banana and Plantain

INFOMUSA is published with thesupport of the Technical Centerfor Agricultural and Rural Cooperation (CTA).

CTA

Vol. 9 No. 1June 2000

IN THIS ISSUESurvey of bananaendophytic fungi fromCentral America andscreening for biologicalcontrol of R. similis

Screening of Fusarium wiltresistant bananas to root-lesion nematodes

Resistance of VietnameseMusa germplasm tonematodes

Somatic embryogenesis inliquid media. Maturationand enhancement ofgermination of FHIA-18

Improvement of FHIA-21hybrid by mutagenesis invitro

Evaluation of Musa spp.for resistance to Moko

Multilocational evaluationof FHIA hybrids in Ghana

Survey on bananas in theDemocratic Republic ofCongo

Round table on cookingbanana in subtropicalzones

Which banana varietyshould I grow?

MusaNews

Thesis

Books etc.

Announcements

INIBAP News

PROMUSA News

2 INFOMUSA — Vol 9, N° 1

Vol. 9, No. 1

Cover photo: Roadside hawkers in India (S. Uma,NRCB)

Publisher:International Network for the Improvementof Banana and Plantain

Managing editor:Claudine Picq

Editorial Committee:Emile Frison, Jean-Vincent Escalant, Suzanne SharrockPrinted in FranceISSN 1023-0076

Editorial Office: INFOMUSA, INIBAP, Parc Scientifique Agropolis II,34397 Montpellier Cedex 5, France. Telephone + 33-(0)4 67 61 13 02; Telefax: + 33-(0)4 67 61 03 34; E-mail: [email protected]

Subscriptions are free for developingcountries readers. Article contributionsand letters to the editor are welcomed.Articles accepted for publication may beedited for length and clarity. INFOMUSAis not responsible for unsolicited mater-ial, however, every effort will be made torespond to queries. Please allow threemonths for replies. Unless accompaniedby a copyright notice, articles appearingin INFOMUSA may be quoted or repro-duced without charge, provided acknowl-edgement is given of the source.French-language and Spanish-languageeditions of INFOMUSA are also published.To avoid missing issues of INFOMUSA, no-tify the editorial office at least six weeksin advance of a change of address.

Views expressed in articles are thoseof the authors and do not necessarilyreflect those of INIBAP.

INFOMUSA Vol. 9, No. 1

CONTENTS

Survey of banana endophytic fungi from Central America and biologicalscreening for control of the burrowing nematode(Radopholus similis) ............................................................................................3

Screening of Fusarium wilt resistant bananas to root-lesion nematodes....................................................................................6

Screening of Vietnamese Musa germplasm for resistance and tolerance to root-knot and root-lesion nematodesin the greenhouse ..............................................................................................8

Somatic embryogenesis in liquid media. Maturation and enhancement of germination of the hybrid cultivarFHIA-18 (AAAB) ................................................................................................12

Improvement of the hybrid plantain clone FHIA-21 by mutagenesis in vitro ....................................................................................16

Evaluation of Musa spp. for resistance to Moko disease (Ralstoniasolanacearum, race 2)........................................................................................19

Multilocational evaluation of FHIA hybrids in Ghana ..........................................20

Results of a survey on bananas conducted among farmers in the DemocraticRepublic of Congo ............................................................................................22

Round table on cooking banana in subtropical zones ........................................24

– Preliminary study on the advantages of the cooking banana ‘Topocho verde’ (ABB) for the Canary Islands ................................................24

– The importance of plantains and cooking bananas in Africa: outlets for thesubtropical zones ..............................................................................................25

– Cooking bananas – Classification, production and utilization in South-EastAsia ....................................................................................................................28

Which banana variety should I grow? ..................................................................31

MusaNews................................................................................................................34

Thesis........................................................................................................................37

Books etc. ................................................................................................................39

Announcements ......................................................................................................39

INIBAP News ............................................................................................................40

PROMUSA News ....................................................................................................I-IV

The mission of the International Network for the Improvement of Banana andPlantain is to sustainably increase the productivity of banana and plantain grownon smallholdings for domestic consumption and for local and export markets.

The Programme has four specific objectives:

• To organize and coordinate a global research effort on banana and plantain,aimed at the development, evaluation and dissemination of improved cultivarsand at the conservation and use of Musa diversity

• To promote and strengthen collaboration and partnerships in banana-relatedresearch activities at the national, regional and global levels

• To strengthen the ability of NARS to conduct research and development activi-ties on bananas and plantains

• To coordinate, facilitate and support the production, collection and exchangeof information and documentation related to banana and plantain.

INIBAP is a programme of the International Plant Genetic Resources Institute(IPGRI), a Future Harvest Centre.

INFOMUSAINFOMUSAThe International Magazine on Banana and Plantain

INFOMUSA is published with thesupport of the Technical Centerfor Agricultural and Rural Cooperation (CTA).

CTA

Vol. 9 No. 1June 2000

IN THIS ISSUESurvey of bananaendophytic fungi fromCentral America andscreening for biologicalcontrol of R. similis

Screening of Fusarium wiltresistant bananas to root-lesion nematodes

Resistance of VietnameseMusa germplasm tonematodes

Somatic embryogenesis inliquid media. Maturationand enhancement ofgermination of FHIA-18

Improvement of FHIA-21hybrid by mutagenesis invitro

Evaluation of Musa spp.for resistance to Moko

Multilocational evaluationof FHIA hybrids in Ghana

Survey on bananas in theDemocratic Republic ofCongo

Round table on cookingbanana in subtropicalzones

Which banana varietyshould I grow?

MusaNews

Thesis

Books etc.

Announcements

INIBAP News

PROMUSA News

L. Pocasangre, R.A. Sikora, V. Vilich and R.P. Schuster

Fungi that colonise healthy planttissue and either persist there ina dormant phase or initiate more

extensive but symptomless infectionsare known as endophytes (Carroll1988, Boddy and Griffith 1989, Yates etal. 1997). When the colonisation leadsto a protection of the tissue against bi-otic and/or abiotic stress, these fungiare called mutualistic (Carroll 1990,Latch 1993).

A survey of endophytic fungi was car-ried out in Central America duringJanuary to February 1997. The surveyed countries were Honduras,Costa Rica, Guatemala and Cuba inthe Caribbean. Eight banana planta-tions were sampled in the region.Twenty-one different Musa spp. culti-vars were sampled, including dessertbanana, cooking banana and plantainbelonging to seven different Musagenomes: AA, AB, AAA, AAB, ABB,AAAB and AABB.

The burrowing nematode Radopholussimilis (Cobb) Thorne is the most im-portant nematode species in bananaand plantain production in CentralAmerica, West Africa and Australia(Pinochet 1986, Sarah 1989, Schipkeand Ramsey 1994). Conventionalplanting material (suckers) is mainlyresponsible for the dispersion of nema-todes into new banana plantations.

The use of tissue culture plantlets pro-vides pest free planting material. How-ever it is well known that tissue cul-ture plantlets are more susceptible tonematodes and Fusarium wilt thansuckers (Musanews 1997, Smith et al.1998). This susceptibility of tissue cul-ture plantlets may be caused by thefact that the plantlets are producedunder aseptic conditions and are freeof mutualistic fungi, which could in-crease root health status of theseplants.

The purpose of this investigation wasto study the natural incidence of endo-phytic fungi on healthy plants of differ-ent banana cultivars in Central Amer-ica and determine the effect of thesefungi on the rate of reproduction of R. similis in inoculated and noninocu-lated tissue culture plantlets on fourcommercial banana cultivars.

Material and methodsCountries surveyed in Central AmericaRoot and corm tissue samples werecollected from eight banana planta-tions from three countries in CentralAmerica: Costa Rica (CATIE, Turrialbaand EARTH, Guacimo), Guatemala(Tiquizate, Molina group plantation),Honduras (FHIA, La Lima, El Rosarioand La Ceiba, Dole plantations) andCuba (Remedios and Antillas, IBP ex-perimental stations).

The banana cultivars surveyed wereselected according to their commer-cial importance for fruit exportation

and for local consumption in the re-gion. All banana plantations surveyedhave been planted with banana as amonocrop for more than 15 years.

Isolation of endophytic fungiThe isolation of endophytic fungi wascarried out from the roots and cormusing the protocol showed in the Fig-ure 1. Primary roots were split into twolongitudinal sections and placed in a5% sodium hypochlorite solution forfive minutes and washed with steriletap water three times. The root sec-tions were placed on autoclaved papertowelling to remove excess water andthe outer layer of root was then peeledoff with a scalpel. The remaining inter-nal tissue was cut into small pieces ofapproximately 1 to 1.5 cm length witha heat sterilized knife. These smallpieces were placed on potato dextroseagar 10% strength (PDA 10%) contain-ing 150 ppm Streptomycin and Peni-cillin. The cultures were incubated at25°C in the dark and the fungi weretransferred to new plates for testingand identification one week later.

The isolation of endophytic fungifrom the corm was done from theouter cortex and central cylinder. Thecorms were split in two longitudinalsections and small blocks of approxi-mately 0.5-1.0 cm length were cut fromtissue and sterilized as describedabove. The fungal isolation was doneusing the protocol described for roots.

Plant materialsTissue culture plantlets of Gran Enano(AAA), Williams (AAA), Gros Michel(AAA) and FHIA-23 (AAAA) were pro-duced using the propagation methodof Wong (1986). The plantlets were ob-tained using lateral shoot tips and in-oculated on medium containing MS Salts (Murashige and Skoog, 1962).The MS medium was supplementedwith 30g/l of Sucrose, 2.5mg/l of Benzy-laminopurine BAP and 0.5mg/l of In-dolacetic acid IAA. The incubationconditions were 25±2 °C and 16 hoursdaylength.

Inoculation and in vivo screening ofendophytic fungiConidial suspensions of endophyticfungi were obtained by using Sun and

Figure 1. Sterilization and isolation protocol used for detection of endophytic fungi from roots andcorm tissue.

INFOMUSA — Vol 9, N° 1 3

Survey of banana endophytic fungi from CentralAmerica and screening for biological control of theburrowing nematode (Radopholus similis)

Biological control Potential of endophytes

longitudinal section of a corm

ccc

longitudinal section ofroots

cc = central cylinder c = cortex

surface sterilizationNaOCl

incubation on agar

transfer of mycelium

pure culture storage

Su’s technique (1984). Cultures of en-dophytic fungi from seven-day-oldgrown on potato dextrose agar were fil-tered through two layers of Cheese-cloth. The conidial suspension was adjusted to 1.2 x 106 cfu/ml by supple-menting Ringer solution. The roots ofplantlets about 12 cm tall were im-mersed in conidial suspension for fiveminutes before replanting in 650 cm3

pots with sterilised sand. The controlplantlets were treated with Ringer so-lution without endophytic fungi. Theplantlets were reinoculated with endo-phytic fungi after two weeks of thefirst inoculation. Reinoculation wasmade around the roots of each plantby pipetting 5ml spores suspension inthree holes at the base of the pseu-dostem. Twenty-eight endophytic fungiisolated from banana roots in CentralAmerica and Africa were screened forantagonistic activity to R. similis onthe cultivar Gran Enano. The most ef-fective endophytic isolates were retestedon four banana cultivars and were alsoused for more detailed studies.

Source of nematodes and inoculationproceduresNematode inoculum consisted of apopulation of R. similis isolated fromthe cultivar Valery in Talamanca, CostaRica. The nematodes were increasedin monoxenic culture on carrot discs(O’Bannon and Taylor 1968). Onemonth after the inoculation with endo-phytic fungi, the plantlets were inocu-lated with 500 nematodes per pot. Ap-plication was made around the roots ofeach plant by pipetting the nematodesuspension into three holes at the baseof the pseudostem.

Two months after inoculation, nema-tode densities were determined in rootsystem and soil. Nematodes in the rootsystem were obtained by cutting freethe whole root system from theplantlets. The root system was stainedin a 0.1% acid-Fuchsin solution andmacerated in a blender for 15s. Nema-todes in two 10-ml aliquots werecounted and the total number of ne-matodes per root system was calcu-lated. Nematodes in the soil were ob-tained by removing a sample of 200gof sand from the pot and placing it ona modified Baermann dish. After twodays, nematodes were collected andconcentrated on a 25µm sieve. Thetotal number of nematodes per pot wasdetermined by calculations based onnematode counts in a 10ml aliquot ofthe total solution.

Statistical analysisThe experimental design used for alltrials was a completely randomised

block design. All data were analysed byanalysis of variance (PROC ANOVA,SAS Version 6.12 for Windows, SAS In-stitute, Cary, USA). Nematode countswere transformed before statisticalanalysis using ln (x + 1). Means werecompared by Duncan’s multiple rangetest (P≤ 0.05).

ResultsA total of 132 endophytic fungi wererecovered from the 120 tissue samplesof the roots and corms in the region.The frequency of occurrence of endo-

phytic fungi was higher in the rootsthan in the cortex and central cylinderof the corm (Table 1).

Fusarium spp. were the predomi-nant endophytic fungus in all coun-tries surveyed and was found in all lo-calities studied. The frequency ofoccurrence of Fusarium spp. washigher in the roots than in the cortexand central cylinder of the corm(Table 2).

Different degrees of activity towardR. similis were found among the endophytic isolates. Three isolates


Table 1. Number of endophytic fungi isolated from different tissue of 21 bananacultivars in Central America.

Country Roots Cortex Central Cylinder Total

Honduras 22 14 8 44

Guatemala 9 6 1 16

Costa Rica 15 4 2 21

Cuba 43 6 2 51

89 (67,5 %) 30 (22,7 %) 13 (9,8 %) 132 (100 %)Values in% are the frequency of occurrence of the fungi per banana tissue.

Table 2. Origin of identified endophytic fungi isolated from different bananacultivars in Central America

Fungus code Fungus genus Cultivar/Genome Tissue Place

Honduras (H)

H-06 Fusarium spp. Giant Cavendish (AAA) central cylinder FHIA collection

H-07 Fusarium spp. Lacatan (AAA) roots FHIA collection

H-12 Fusarium spp. Cavendish (AAA) roots FHIA collection

H-14* Fusarium spp. Cavendish (AAA) roots FHIA collection

H-15 Trichoderma sp. Cavendish (AAA) central cylinder FHIA collection

H-19* Fusarium spp. Bluggoe (ABB) roots FHIA collection

H-20* Fusarium spp. Dwarf Cavendish (AAA) roots FHIA collection

H-26* Fusarium spp. Ney Poovan (AB) roots FHIA collection

H-31 Verticillium spp. P.J. Buaya (AA) cortex FHIA collection

H-35 Fusarium spp. Gran Enano (AAA) roots Dole, Rosario

H-36 Fusarium spp. Gran Enano (AAA) cortex Dole, Rosario

H-37 Acremonium spp. Gran Enano (AAA) cortex Dole, Rosario

H-39 Fusarium spp. Gran Enano (AAA) roots Dole, La Ceiba

H-42 Fusarium spp. Gran Enano (AAA) cortex Dole, La Ceiba

H-43 Fusarium spp. Gran Enano (AAA) cortex Dole, La Ceiba

Costa Rica (CR)

CR-01 Fusarium spp. Gran Enano (AAA) roots CATIE, Turrialba

CR-04 Fusarium spp. Gran Enano (AAA) roots CATIE, Turrialba

CR-09 Fusarium spp. Gran Enano (AAA) roots EARTH, Guacimo

CR-10 Fusarium spp. Gran Enano (AAA) roots EARTH, Guacimo

CR-19 Fusarium spp. Gran Enano (AAA) cortex EARTH, Guacimo

CR-21 Acremonium spp. Gran Enano (AAA) cortex EARTH, Guacimo

Guatemala (G)

G-01 Fusarium spp. Gran Enano (AAA) roots Tiquizate

G-05 Verticillium spp. Gran Enano (AAA) roots Tiquizate

G-08 Fusarium spp. Gran Enano (AAA) cortex Tiquizate



Cuba (C)

C-03 Fusarium spp. FHIA-01 (AAAB) roots IBP, Remedios

C-09 Fusarium spp. FHIA-03 (AABB) roots IBP, Antillas

C-13* Fusarium spp. FHIA-03 (AABB) roots IBP, Antillas

C-20 Fusarium spp. FHIA-03 (AABB) roots IBP, Remedios

C-22 Fusarium spp. FHIA-03 (AABB) roots IBP, Remedios


C-39 Fusarium spp. Gros Michel (AAA) roots IBP, Remedios


C-49 Fusarium spp. FHIA-21 (AAAB) roots IBP, Remedios* Effective endophytic fungi, which caused reduction in the number of R. similis/g root higher than 80% in relation to control.

caused a reduction in the number of R. similis/g root higher than 90% onthe cultivar Gran Enano and only nineof 28 isolates were considered less ac-tive with a reduction lower than 30%(Table 3). The most effective endo-phytic isolates: H-14, H-19, H-20, H-26and C-13 were retested on four bananacultivars: Gran Enano, Williams, GrosMichel and FHIA-23 and the fungiwere able to cause reductions in thenumber of R. similis/g root higherthan 80% on all banana cultivars (datanot shown). These effective endo-phytic isolates were also used for moredetailed studies that are not includedin this publication.

DiscussionThe results of this survey demon-strated that the frequency of occur-rence of endophytic fungi was higherin the roots than in the cortex andcentral cylinder of the corm of com-mercial banana cultivars. From 132fungi isolated, 89 were isolated fromthe roots, 30 from the cortex and 13from the central cylinder of the corm.

Fusarium spp. are found in bananaas natural endophytes and have beendetected in the roots of different ba-nana cultivars in several countries(Speijer 1993, Amin 1994, Schuster etal. 1995). The results of this surveydemonstrated that the most frequentlyfound endophytic fungi isolated werestrains of Fusarium. The fungi werefound in the eight localities sampled inCentral America and Cuba in theCaribbean. Strains of Fusarium spp.were isolated from different bananacultivars, including dessert, cookingand plantain belonging to diploids,triploids and tetraploids genomes.These results suggest that Fusariumspp. are natural endophyte in bananaand the fungi are not restricted to acultivar or genomes as a particularhost.

Different degrees of activities to-ward R. similis were found among the28 Fusarium spp. isolates used inscreening studies on the cultivar GranEnano. 11 isolates caused a reductionin the number of R. similis/g roothigher than 70%. In contrast, only nineof 28 isolates were considered less ac-tive due to the their reduction activitywas lower than 30%. These differencesin activity among the isolates may beexplained by the ability of the fungi togrow extensively inside and then im-pede the penetration of nematodes inthe roots (Pocasangre et al., unpub-lished). Hallmann and Sikora (1996)found that non-pathogenic Fusariumoxysporum strains were the most ef-fective endophytic fungi toward plant

parasitic nematodes. They also foundthat the toxic metabolites produced byFusarium oxysporum were highly ef-fective towards sedentary parasitesand less effective towards migratoryendoparasites.

The results of our investigations sug-gest that the endophytic fungi could beused to improve the critical hardeningphase of banana micropropagation andreduce initial applications of pesti-cides at this stage. The duration of bio-logical control as the plant maturesstill needs further study.

AcknowledgementsThe authors would l ike to thank Dr Phil Rowe (FHIA, Honduras), Dr Roberto Young (Dole, Honduras),Dr Panfilo Tabora (EARTH, CostaRica), Mr Amnon Ronen (Galitec,Guatemala) and Dr Juan Peréz Ponce(IBP, Cuba) for the local arrange-ments and provided transportationfor collecting the samples from thebanana plantations. We are alsograteful to M.Sc. Miguel Dita, M.Sc.Yelenys Capo (IBP, Cuba) and DrMauricio Rivera (FHIA, Honduras)for technical assistance and labora-tory facilities for the isolation offungi. This work was funded by theGerman Academic Exchange Service(DAAD) and Standard Fruit Company(Dole, Honduras). �

ReferencesAmin N. 1994. Untersuchungen Ÿber die bedeutung

endophytischer pilze fŸr die biologische bekˇmp-fung des wandernden endoparasiten Radopholussimilis (Cobb) Thorne an Bananen. Ph.D. The-sis, University of Bonn, 112 pp.

Boddy L. & G.S. Griffith. 1989. Role of endophytesand latent invasion in the development of decaycommunities in sapwood of angiospermous trees.Sydowia 41: 41-73.

Carroll G.C. 1988. Fungal endophytes in stems andleaves: from latent pathogen to mutualistic sym-biotic. Ecology 69: 2-9.

Carroll G.C. 1990. Fungal endophytes in vascularplants: Mycological research opportunities inJapan. Trans. Mycol. Soc. Japan 31: 103-116.

Hallmann J. & R.A. Sikora. R.A. 1996. Toxicity offungal endophyte secondary metabolites to plantparasitic nematodes and soil-borne plant patho-genic fungi. European Journal of Plant Pathology102: 155-162.

Latch G.C.M. 1993. Physiological interactions of en-dophytic fungi and their hosts. Biotic stress tol-erance imparted to grasses by endophytes. Agri-culture, Ecosystems and Environments 44: 143-156.

Murashige T. & F. A Skoog. 1962. A revised mediumfor rapid growth and bioassays with tobacco tis-sue cultures. Plant Physiology, 15:473-497.

Musanews 1997. Latin America and the Caribbeannews. INFOMUSA 6 (2): 52-57.

O’Bannon J. H. & A.L. Taylor. 1968. Migratory en-doparasitic nematodes reared on carrot discs.Phytopathology 58: 385.

Pinochet J. 1986. A note on nematode control prac-tice on bananas in Central America. Nematrop-ica 16(2): 197-203.

Sarah J-L. 1989. Banana nematodes and their con-trol in Africa. Nematropica 19(2): 199-217.

Schipke L.G. & M.D. Ramsey. 1994. Control of ba-nana burrowing nematode (Radopholus similis)by fenamiphos applied through micro-irrigationin North Queensland. Austr. J. of Experim. Agric.34: 109-114.

Schuster R.P., R.A. Sikora & N. Amin. 1995. Poten-tial of endophytic fungi for the biological controlof plant parasitic nematodes. Med. Fac. Land-bouww. University of Gent 60/3b: 1947-1952.

Smith M. K, A.W. Whiley, C. Searle, P.W. Langdon,B. Schaffer & K. C. Pegg. 1998. Micropropagatedbananas are more susceptible to Fusarium wiltthan plant grown from conventional material.Aust. J. Agric. Res. 49: 1133-1139.

Speijer P.R. 1993. Interrelationships betweenPratylenchus goodeyi Sher & Allen and strainsof non-pathogenic Fusarium oxysporum Schl.Emd. Snyd. & Hans. in roots of two banana culti-vars. Ph. D. Thesis, University of Bonn, 200 pp.

Sun E.J. & H.J. Su. 1983. Rapid method for deter-mining differential pathogenicity of Fusariumoxysporum f.sp. cubense using banana plantlets.Trop. Agric. 61(1): 7-8.

Wong W.C. 1986. In vitro propagation of banana(Musa spp.): Initiation, proliferation and devel-opment of shoot-tip culture on defined media.Plant Cell Tissue and Organ Culture 6: 159-166.

Yates I.E., C.W. Bacon & D.M. Hinton. 1997. Effectsof endophytic infection by Fusarium monili-forme on corn growth and cellular morphology.Plant Diseases 81: 723-728.


Table 3. Classes of activity of 28Fusarium spp. isolates on thereproduction rate of Radopholus similison the cultivar Gran Enano (AAA).

Classes Number % of of activity of isolates isolates

negative effect 2 7

< 30 % 7 25

30-50 % 3 11

50-70 % 5 18

71-90 % 8 28

> 90 % 3 11

Total 28 100Values in percentages are the reduction in the number of R. similis in relation to control plantlets.

The authors work at the Institute of Plant Pathol-ogy, Soil-Ecosystem Phytopathology Section, Univer-sity of Bonn, Nussallee 9, D-53115 Bonn, Germany.

R. Stoffelen, R. Verlinden, J. Pinochet, R. Swennen

and D. De Waele

Many important banana geno-types and most of the world’sbanana production areas are

affected by Fusarium wilt or Panamadisease caused by the soilborne fungusFusarium oxysporum f. sp. cubense(Foc). The fungus colonizes and oc-cludes the xylem of the host plant andcauses thereby reddish-brown discol-oration. Leaves become bright yellow,wilt and collapse around the pseu-dostem (Ploetz 1994). The pathogencan survive for long periods in the soiland cannot be controlled with fungi-cides. As a consequence, susceptiblegenotypes cannot be grown in an in-fested field for up to 30 years.

In the framework of the InternationalMusa Testing Programme (IMTP)phase II of INIBAP, the resistance ofimproved banana and plantain hybridsto Fusarium wilt was evaluated (Or-jeda 1998). As a result of this pro-gramme, several sources of resistanceto these fungal diseases are now avail-able (Shepherd et al. 1994, Pires deMatos et al. 1998, Orjeda et al. 1999,Tang and Hwang 1999).

Banana and plantain are not only at-tacked by fungi but also by otherpathogens including plant-parasitic ne-matodes of which Radopholus similis,Pratylenchus coffeae, Pratylenchusgoodeyi, Helicotylenchus multicinctusand Meloidogyne spp. are the most com-mon and damaging species (Gowen andQuénéhervé 1990). In nematode-infestedfields, losses caused by reduced plantgrowth, longer vegetative period, smallerbunches, toppling and reduced longevityof the plantation can be very high.

The objective of this study was toevaluate ten Fusarium wilt resistant ormoderately resistant Musa genotypes,as identified by IMTP, on their resis-tance to the root-lesion nematodes R. similis and P. coffeae. Three suscep-tible reference genotypes ‘Gros Michel’,‘Williams’ and ‘Bluggoe’ were includedas well (Jones 1994). The resistance toP. goodeyi and Meloidogyne spp. ofthese genotypes was recently evaluatedby Pinochet et al. (1998). Throughout

the study, the methodology as de-scribed by Speijer and De Waele (1997)was followed.

Materials and methodsPreparation of plantsIn vitro propagated plantlets weretransplanted in 1-liter plastic potsfilled with autoclaved loamy sand. Thepots were maintained in a greenhouseat an ambient temperature of 20-27°Cand a 12-hour photoperiod. The potswere irrigated as needed and fertilizedwith a hydroponic solution every threeweeks after nematode inoculation.

Preparation of nematode inoculumThe R. similis and P. coffeae popula-tions used were originally isolatedfrom infected Musa roots: R. similisfrom a banana cultivar ‘Valery’ (AAA-group) in Talamanca, Costa Rica, andP. coffeae from a plantain (AAB-group)in Kade, Ghana. Radopholus similisand P. coffeae were reared monoxeni-cally on carrot disk cultures at 28°C inthe dark (Moody et al. 1973, Pinochetet al. 1995). The inoculum was ad-justed to deliver a suspension of nearly1000 eggs and vermiform living nema-todes per plant in 3 holes made in thesoil around the roots.

Estimation of host plant resistanceThe plants were inoculated with nematodesfour weeks after acclimatization. Plants in-oculated with R. similis were harvested ateight weeks after inoculation and thosewith P. coffeae two weeks later because ofthe longer life cycle of this nematode. Asubsample of 15 g of fresh roots was macer-ated in a blender during two periods of 10Óseparated by a 5Ó interval. The nematodeswere then passed through 250, 106 and 40mm-pore sieves. The nematodes remainingon the 40 µm-pore sieve were collected andcounted in 6-ml aliquots of each sampleusing a binocular microscope.

Experimental design and data analysisThe genotypes were divided into twobatches, each including ‘Grande Naine’(AAA-group) as susceptible reference culti-var. Four successive experiments were con-ducted to determine the host plant re-sponse of the genotypes of both batches toR. similis and P. coffeae. Each experimentwas a randomized complete block with

eight replicates per genotype. Nematodenumbers were log10(x + 1) transformed andsubjected to analysis of variance (ANOVA).The means were separated by Tukey’s testat P < 0.05.

ResultsRadopholus similisIn batch 1, significant differences in sus-ceptibility to R. similis were observed(Table 1). The nematode numbers per rootsystem of the two ‘Pisang Jari Buaya’ acces-sions and ‘Yangambi Km5’ were signifi-cantly lower compared to the susceptiblereference cultivar ‘Grande Naine’. Becausethe numbers of nematodes recovered perroot system were lower than the inoculum,the ‘Pisang Jari Buaya’ accessions ITC0312and ITC0690 and ‘Yangambi Km5’ can beconsidered resistant to R. similis. The sus-ceptibility to R. similis of the genotypes‘Gros Michel’, ‘FHIA-01’ and ‘Bluggoe’ wasnot significantly different from ‘GrandeNaine’.

All genotypes screened in batch 2 werestatistically as susceptible to R. similis as‘Grande Naine’: ‘PA 03.22’, ‘PV 03.44’, ‘P.lilin’, ‘Saba’, ‘GCTCV 215’, ‘GCTCV 119’ and‘Williams’ (Table 1). Only the nematodenumbers recovered from ‘PA 03.22’ were sig-nificantly lower compared to ‘Williams’.

Pratylenchus coffeaeAll genotypes screened in batches 1and 2 were statistically as susceptibleto P. coffeae as ‘Grande Naine’, the sus-ceptible reference cultivar (Table 1).In batch 1, the highest number of ne-matodes per root system was recov-ered from ‘Bluggoe’. ‘Bluggoe’ was sig-nificantly more susceptible to P. coffeae compared to all other geno-types evaluated in batch 1 except‘Grande Naine’. In batch 2, the highestnumber of nematodes per root systemwas recovered from ‘Saba’. ‘Saba’ wassignificantly more susceptible to P. coffeae compared to all other geno-types evaluated in batch 2, including‘Grande Naine’ (Table 1).

DiscussionOut of the 14 Musa genotypes threeshow resistance to R. similis : the‘Pisang Jari Buaya’ accessions ITC0312and ITC0690, and ‘Yangambi Km5’. Theresistance of ‘Pisang Jari Buaya’ and‘Yangambi Km5’ to R. similis has beenreported previously (Wehunt et al.1978, Pinochet and Rowe 1979, Price1994, Fogain and Gowen 1998). The‘Pisang Jari Buaya’ accessions belongto the Pisang Jari Buaya subgroupwhich consists of diploid AA varieties ofwhich several varieties showed either


Improvement Nematode resistance evaluation

Screening of Fusarium wiltresistant bananas to root-lesionnematodes

resistance to or are less susceptible toR. similis (Wehunt et al. 1978). Our ob-servations that two accessions of‘Pisang Jari Buaya’ originating from dif-ferent localities (accession ITC0312from Malaysia; accession ITC0690 fromIndonesia) are resistant to R. similisreconfirm the status of this genotype asR. similis resistant. The use of ‘PisangJari Buaya’ in the Musa breeding pro-gramme of the Fundación Hondureñade Investigación Agrícola (FHIA) inHonduras, resulted in the release of thecommercial hybrid ‘FHIA-01’ (AAAB)(Rowe and Rosales 1993). Recent stud-ies showed that ‘FHIA-01’ was partiallyresistant to R. similis when 3- to 4-months-old plants grown from cormswere evaluated. However, plants grownfrom in vitro maintained tissue cultureplants were as susceptible to R. similisas the susceptible reference cultivars(INIBAP 1998). Our results confirmthat ‘FHIA-01’ plants derived from invitro propagation are not resistant toR. similis at least during eight weeksafter inoculation.

‘Yangambi Km5’, the second source ofresistance to R. similis, is a triploidAAA variety collected in the Democra-tic Republic of Congo. Although maleand female fertile, this variety is notbeing used in Musa breeding pro-grammes because all progenies pro-duce abnormal leaves and/or erect andsemi-erect bunches.

‘Gros Michel’ is reported as a cultivarwith lower susceptibility to R. similiscompared with the susceptible cultivar

‘Poyo’ (AAA-group) (Mateille 1992,Price 1994). In this study the host plantresponse of ‘Gros Michel’ is not clearbecause the number of nematodes perroot system is not significantly differentfrom the susceptible reference cultivar‘Grande Naine’ and from the resistant‘Pisang Jari Buaya’ accessions and‘Yangambi Km5’.

None of the 14 Musa genotypes evalu-ated in this study is resistant to P. coffeae. These results confirm earlierreports on the susceptibility of ‘PisangJari Buaya’ to P. coffeae (Pinochet andRowe 1978, INIBAP 1998). Partial resis-tance of ‘Yangambi Km 5’ to P. coffeae isobserved on in vitro plants and cormsafter inoculation (INIBAP 1998). How-ever in this study, ‘Yangambi Km5’ wasas susceptible to P. coffeae as the refer-ence cultivar ‘Grande Naine’.

All Musa sources of resistance to F. oxysporum f. sp. cubense with excep-tion of ‘Pisang Jari Buaya’ and‘Yangambi Km5’, are highly susceptibleto both R . similis and P. coffeae .Screening by Pinochet et al. (1998) re-vealed that all genotypes were also sus-ceptible to Meloidogyne javanica andM. incognita and were good hosts for P. goodeyi except ‘Yangambi Km 5’.When these genotypes are grown infields infested with these nematodesyield losses may be expected.

AcknowledgementsThe authors thank the late P. Speijer(IITA, Uganda) and J.L. Sarah (CIRAD-AMIS) for supplying nematode popula-

tions and I. Van den Houwe (INIBAPTransit Center) for supplying the Musagermplasm. Technical assistance wasgiven by J. Reynders (K.U.Leuven). Thisresearch was financed by the CommonFunds for Commodities/FAO/WorldBank Banana Improvement Project andthe Catholic University of Leuven(K.U.Leuven). This research was car-ried out within the framework of theNematology working group of theGlobal Programme for Musa Improve-ment-PROMUSA. �

ReferencesFogain R. & S.R. Gowen. 1998. Yangambi Km 5

(Musa AAA, Ibota subgroup) a possible source ofresistance to Radopholus similis and Praty-lenchus coffeae. Fundamental and Applied Ne-matology 21: 75-80.

Gowen S.R. & P. Quénéhervé. 1990. Nematode para-sites of bananas, plantains and abaca. Pp. 431-460 in Plant Parasitic Nematodes in Subtropicaland Tropical Agriculture. (M. Luc, R.A. Sikora &J. Bridge, eds.). CAB International, Wallingford,United Kingdom.

INIBAP. 1998. INIBAP Annual Report 1997. INI-BAP, Montpellier, France.

Jones D.R. 1994. International Musa Testing Pro-gramme Phase II. Pp. 23-31 in The Improvementand Testing of Musa: a Global Partnership. (D.R.Jones, ed.). INIBAP, Montpellier, France.

Mateille T. 1992. Comparative development of threebanana-parasitic nematodes on Musa acumi-nata (AAA group) cvs Poyo and Gros Michelvitro-plants. Nematologica 38: 203-216.

Moody E.H., B.F. Lownsberry & J.M. Ahmed. 1973.Culture of the root-lesion nematode Praty-lenchuvulnus on carrot disks. Journal of Nema-tology 5: 225-226.

Orjeda G. 1998. Evaluation of Musa germplasm forresistance to Sigatoka disease and Fusarium wilt.INIBAP Technical Guidelines 3. IPGRI, Rome,Italy; INIBAP, Montpellier, France; CTA, Wa-geningen, The Netherlands.

Orjeda G., J.V. Escalant & N. Moore. 1999. The In-ternational Musa Testing Programme (IMTP)phase II overview of final report and summary ofresults. INFOMUSA 8(1): 3-10.

Pinochet J. & P.R. Rowe. 1978. Reaction of two ba-nana cultivars to three different nematodes.Plant Disease Reporter 62: 727-729.

Pinochet J. & P.R. Rowe. 1979. Progress in breedingfor resistance to Radopholus similis on bananas.Nematropica 9: 76-78.

Pinochet J., C. Fernandez, C. & J.L. Sarah. 1995. In-fluence of temperature on in vitro reproductionof Pratylenchus coffeae , P. goodeyi , andRadopholus similis. Fundamental and AppliedNematology 18: 391-392.

Pinochet J., M.C. Jaizme, C. Fernandez, M. Jaumotand D. De Waele. 1998. Screening bananas forroot-knot nematode (Meloidogyne spp.) and le-sion nematode (Pratylenchus goodeyi) resis-tance for the Canary Islands. Fundamental andApplied Nematology 21: 17-23.

Pires de Matos A., M. de Freitas Borges, S. deOliviera e Silva, Z.J. Maciel Cordiero & S. de

Table 1. Nematode reproduction on ten Fusarium resistant and three Fusariumsusceptible genotypes and the reference cultivar ‘Grande Naine’ measured eight (R. similis) or ten (P. coffeae) weeks after inoculation.

Accession name Reaction to ITC Numbers of Numbers of Fusarium code R. similis P. coffeae per

per root system root system

Batch 1 Pi= 1006 eggs Pi= 1004 eggs and vermiforms and vermiforms

Pisang Jari Buaya resistant 0312 673 a 1673 a

Yangambi Km5 resistant 1123 792 a 1724 a

Pisang Jari Buaya resistant 0690 999 a 1374 a

Gros Michel susceptible 1122 2513 ab 1392 a

FHIA-01 resistant 0504 3790 bc 1585 a

Bluggoe susceptible 0643 9786 c 4590 B

Grande Naine 1256 6761 bc 2082 ab

Batch 2 Pi= 926 eggs Pi= 1178 eggs and vermiforms and vermiforms

PA 03.22 resistant 1261 4987 A 9530 B

PV 03.44 resistant 1262 8400 AB 6298 AB

Pisang lilin resistant 0001 10 857 AB 8731 AB

Saba resistant 1138 12 754 AB 27 817 C

GCTCV 215 resistant 1271 13 156 AB 4454 A

GCTCV 119 resistant 1282 14 686 AB 8278 AB

Williams susceptible 0570 23 216 B 12 936 B

Grande Naine 1256 14 686 AB 9601 ABITC = INIBAP Transit Center; Pi = initial population.

Data were log10(x + 1) transformed before analysis. Means in the same column followed by the same letter do not differsignificantly according to Tukey’s method (P<0.05).


Moraes Andrade. 1998. Reaction of banana geno-types to Fusarium wilt (Fusarium oxysporumf.sp. cubense) under field conditions in Brazil.Pp. 311-319 in Memorias XIII Reunión ACOR-BAT, Guayaquil, Ecuador, 23-27 Noviembre, 1998.(Arizaga, ed.). CONABAN, Guayaquil, Ecuador.

Ploetz R.C. 1994. Fusarium wilt and IMTP Phase II.Pp. 57-69 in The Improvement and Testing ofMusa: a Global Partnership. (D.R. Jones, ed.).INIBAP, Montpellier, France.

Price N.S. 1994. Field trial evaluation of nematodesusceptibility within Musa. Fundamental and Ap-plied Nematology 17: 391-396.

Rowe P. & F. Rosales. 1993. Diploid breeding atFHIA and the development of Goldfinger (FHIA-01). INFOMUSA 2: 9-11.

Shepherd K., J.L.L. Dantas & S. de Oliveira e Silva.1994. Breeding Prata and MaVa cultivars inBrazil. Pp. 157-168 in The Improvement andTesting of Musa: a Global Partnership. (D.R.Jones, ed.). INIBAP, Montpellier, France.

Speijer P. & D. De Waele. 1997. Screening of MusaGermplasm for Resistance and Tolerance to Ne-matodes. INIBAP Technical Guidelines 1. IPGRI,Rome, Italy; INIBAP, Montpellier, France; CTA,Wageningen, The Netherlands.

Tang C.Y. & S.C. Hwang, 1999. Performance of ba-nana clones under the challenge of Fusariumwilt in Taiwan. INFOMUSA 8(1): 10-12.

Wehunt E.J., D.J. Hutchinson & D.I. Edwards. 1978.Reaction of banana cultivars to the burrowingnematode (Radopholus similis). Journal of Ne-matology 10: 368-370.


Ruth Stoffelen, Raf Verlinden, Rony Swennenand Dirk De Waele work at the Laboratory of Tropi-cal Crop Improvement, Catholic University of Leuven(K.U.Leuven), K. Mercierlaan 92, 3001 Heverlee, Bel-gium. Jorge Pinochet works at Agromillora CatalanaS. A., El Rebato, s/n, 08739 T. M. Subirats, Spain.

Genetic resources Early screening of nematode resistance

I. Van den Bergh, D. De Waele, Ho Huu Nhi, Duong Thi Minh Nguyet,

Nguyen Thi Tuyet and Doan Thi Thanh

Vietnam lies in the origin centre ofbananas, with excellent condi-tions for banana production.

Among the fruit crops, bananas rankfirst in terms of gross output and pro-duction area (Vinh and Quy 1995). Ba-nanas are mostly grown for domesticconsumption.

During 1994-1995, a banana collec-tion mission was held in Vietnam.More than 80 genotypes and wildspecies were collected (Khoi and Val-mayor, 1995). Following preliminarycharacterisation, 64 distinct genotypesand 9 wild species have been identi-fied (INIBAP 1997). These genotypesare being maintained in a field collec-tion at the Phu Ho Fruit Research In-stitute (Vinh Phu province) and in anin vitro collection at the Vietnam Agri-cultural Science Institute (Hanoi). Apart has also been sent to the INIBAPTransit Centre (ITC) in Leuven (Bel-gium) to be included in the world col-lection of bananas.

These genotypes must now be evalu-ated for their overall performance andtheir disease and pest resistance/toler-ance characteristics. In this study, themost important genotypes werescreened for their resistance/toleranceto Meloidogyne spp., root-knot nema-todes that cause galling of the primary

and secondary roots (De Waele andDavide 1999), and P. coffeae, root-le-sion nematodes that cause a necroticand reduced root system (Stoffelen etal. 1999).

Materials and methodsTwo experiments with Meloidogynespp. and two with P. coffeae were car-ried out. The genotypes used in the ex-periments are listed in Table 1. Intotal, 19 Vietnamese banana genotypesand two genotypes received from ITCwere screened. The genotypes‘Yangambi Km 5’, ‘Gros Michel’ and‘Grand Nain’ were included as refer-ence genotypes: highly resistant toR. similis, moderately resistant toR. similis and susceptible to all nema-todes, respectively (Speijer and DeWaele 1997).

For all the experiments, in vitroplantlets were used. The plantletswere cultured and propagated onMurashige and Skoog (1962) medium.They were transferred to trays, filledwith sterilised sand and treated sev-eral times with the fungicide Daconil.After two to three weeks, the plantswere transferred to 12-cm-diameterplastic pots, filled with a mixture ofsterilised soil and humus. They wereagain treated with Daconil and alsowith the insecticides Suprathion,Ortus, Trebon or Dipterex. The plantswere watered as needed and a nutri-tional solution was applied two times.

After 6 to 14 weeks, 20 plants ofevery genotype were chosen at random

and arranged in a randomised com-plete block design. Of every genotype,10 plants were infested with 4000 juve-niles and eggs of Meloidogyne spp., ob-tained from mixed tomato roots, or 1000 vermiform nematodes of P. coffeae, obtained from mixed carrotdiscs (O’ Bannon and Taylor 1968).The 10 other plants were used as con-trol plants.

The plants were harvested 11 to 15weeks after inoculation. Several datawere recorded to assess the damagecaused by the nematodes (a measurefor the tolerance/sensitivity of thegenotypes) and the reproduction ofthe nematodes (a measure for the re-sistance/susceptibility of the geno-types).

Following the method described bySpeijer and de Waele (1997), the fol-lowing data were recorded:

General data: plant height (cm),shoot weight (g), weight of the rootsystem (g), number of standing leaves,girth at the base (cm).

Data on nematode reproduction:number of egg-laying females on the sec-tion of five 10-cm, pieces of roots (ELF),for experiment with Meloidogyne spp.,nematodes per 10 g of roots and per rootsystem.

Data on root damage assessment:percentage of dead roots (%), root-knot galling (RKG), for experimentwith Meloidogyne spp., root necrosisindex (RNI, %), for experiment withP. coffeae.

The maceration-sieving method wasused for the extraction of the nema-todes.

For the statistical analysis of the re-sults, the software package SPSS 9.0for Windows was used. For normal pop-ulations, ANOVA was used to analyzethe data and mean separation was per-formed with Tukey’s Honestly Signifi-cant Difference Test. For non-normalpopulations, the non-parametricKruskal-Wallis Rank Test was used toanalyse the data and mean separation

Screening of Vietnamese Musa germplasm for resistance and tolerance to root-knot and root-lesion nematodes in the greenhouse

was performed with the KW-Bonfer-roni Method. The combined confi-dence level of all the paired tests is atleast 0.95 (combined confidence coef-ficient α = 0.05).

Results and discussionMeloidogyne spp.General dataIn the first experiment, infection withMeloidogyne spp. resulted in an in-crease in the weight of the root systemand a decrease in the number of stand-ing leaves. There was no effect on theplant height, the shoot weight or thegirth of the plants. In the second ex-periment, infection with Meloidogynespp. had no effect on any of the mea-sured general data (Table 2).

Nematode reproductionIn the first experiment, there were nodifferences in the numbers of nema-todes of the different genotypes. In thesecond experiment, there were no dif-ferences in the numbers of egg-layingfemales or the numbers of nematodes

per 10 g of roots of the different geno-types, but there were some significantdifferences in the numbers of nema-todes per root system of the differentgenotypes. ‘Ngu Thoc’ had a signifi-cantly lower number of nematodes perroot system than ‘Tieu Vua Trang’,‘Com Chua’ and ‘Ben Tre’ (Table 3).

Root damage assessmentThere were never differences in thepercentages of dead roots of the differ-ent genotypes, but in both experi-ments, some significant differences inthe root-knot galling of the differentgenotypes could be detected. In thefirst experiment, ‘Yangambi Km 5’showed a significantly lower root-knotgalling than ‘Voi’. In the second experi-ment, ‘Man’, ‘Ngu Thoc’ and ‘Tay’showed a significantly lower root-knotgalling than ‘Ben Tre’ (Table 3).

Discussionin the first experiment, the knotsformed by Meloidogyne spp. can prob-ably explain the increase in the weight

of the root system of the infectedplants. In the second experiment, theaverage root-knot galling was muchlower than in the first experiment (0.8in comparison to 2.4), which might ex-plain why in the second experiment,infection with Meloidogyne spp. hadno effect on the root weight. The num-ber of egg-laying females and nema-todes per 10 g of roots and per rootsystem was also lower in the secondexperiment than in the first (Table 3).This might explain why in the secondexperiment, infection with Meloidog-yne spp. had no effect on the numberof standing leaves.

In the first experiment, all the geno-types showed the same level of resis-tance/susceptibility to Meloidogynespp. The second experiment indicatesthat ‘Ngu Thoc’ might show some resis-tance to Meloidogyne spp., while ‘TieuVua Trang’, ‘Com Chua’ and ‘Ben Tre’are probably very susceptible toMeloidogyne spp. These results arehowever not very convincing and fur-ther research is needed.

In both experiments, there weresome significant differences in theroot-knot galling of the different geno-types, which indicates the existence ofdifferences in tolerance/sensitivity ofthe genotypes to Meloidogyne spp.‘Yangambi Km 5’, ‘Man’, ‘Ngu Thoc’ and‘Tay’ possibly show some tolerance tothe gall-forming activity of Meloidog-yne spp. For ‘Ngu Thoc’, the low root-knot galling could also be a conse-quence of the low number ofnematodes in the roots instead of anevidence of tolerance. ‘Voi’ and ‘BenTre’ are probably highly sensitive tothe gall-forming activity of Meloidog-yne spp.

P. coffeaeGeneral dataIn the first experiment, infection withP. coffeae resulted in a decrease in theheight of the plants and the shootweight. There was no effect on theweight of the root system, the numberof standing leaves or the girth of theplants. In the second experiment, in-fection with P. coffeae had no effect


Table 1. Genotypes used in the screening experiments.

Name Group VN- number ITC code Meloidogyne spp. P. coffeae

1998 1999 1998 1999

‘Tay But’ AA VN1-001 ITC1367 ✔ ✔ ✔

‘Ngu Tien’ AA VN1-004 ITC1420 ✔ ✔

‘Com Lua’ AA VN1-117 ITC1421 ✔ ✔

‘Ngu Thoc’ AA VN1-017 ITC1358 ✔ ✔

‘Tien’ AA VN1-075 ITC1368 ✔

‘Tieu Mien Nam’ AA VN1-120 ITC1370 ✔ ✔

‘Tieu Xanh’ AAA VN1-006 ITC1406 ✔ ✔

‘Tieu Cao’ AAA VN1-042 ITC1376 ✔ ✔

‘Tieu Vua Trang’ AAA VN1-064 ✔ ✔

‘Ben Tre’ AAA VN1-065 ITC1410 ✔

‘Cao Hong’ AAA VN1-079 ITC1407 ✔ ✔ ✔

‘Man’ AAB VN1-035 ITC1379 ✔ ✔

‘Com Chua’ AAB VN1-116 ITC1380 ✔ ✔

‘Xiem Mat’ AAB VN1-141 ITC1425 ✔ ✔

‘Voi’ AAB VN1-144 ITC1381 ✔ ✔

‘Tay’ ABB VN1-012 ITC1426 ✔

‘Gao’ ABB VN1-015 ITC1357 ✔ ✔

‘Ngop Lun’ ABB VN1-024 ✔ ✔

‘Ngop Cao’ ABB VN1-025 ITC1364 ✔ ✔

‘FHIA-23’ AAAA ITC1265 ✔ ✔

‘Kluai Hom Khom’ AAA ITC0527 ✔ ✔

‘Yangambi Km 5’ AAA ITC1123 ✔ ✔ ✔

‘Gros Michel’ AAA ITC1122 ✔ ✔

‘Grand Nain’ AAA ITC1256 ✔ ✔

Table 2. Meloidogyne spp.: results of the general data of the experiments.

Plant height (cm) Shoot weight (g) Root weight (g) Standing leaves Girth (cm)

Experiment 1998 A B C D E

Not infected with Meloidogyne spp. 27.6 a 81.8 a 28.3 a 6.7 b 8.2 a

Infected with Meloidogyne spp. 27.8 a 79.0 a 31.6 b 6.2 a 8.3 a

Experiment 1999 F G H I J

Not infected with Meloidogyne spp. 28.2 a 117.2 a 52.6 a 5.7 a 10.5 a

Infected with Meloidogyne spp. 27.5 a 112.8 a 54.7 a 5.7 a 10.4 aA, D, E, I, J: Data were not transformed before analysis.

B, F, H: Data were log10x transformed before analysis. The untransformed data are presented in the table.

C, G: Data were square root transformed before analysis. The untransformed data are presented in the table.

Means in the same column followed by the same letter do not differ significantly according to Tukey (A, B, C, F, G, H) or KW-Bonferroni (D, E, I, J) for α= 0.05.

on any of the measured general data(Table 4).

Nematode reproductionIn the first experiment, ‘Yangambi Km5’ and ‘Tieu Xanh’ had a lower numberof nematodes than ‘Ngop Lun’ and‘Voi’. In the second experiment, ‘NgopCao’ was the only genotype with a highnumber of nematodes (Table 5).

Root damage assessmentThere were never differences in thepercentages of dead roots of the differ-ent genotypes. Only in the first experi-ment, some significant differences inthe root necrosis of the different geno-types could be detected. ‘Yangambi Km5’ showed a significantly lower rootnecrosis than ‘Ngop Lun’ (Table 5).

DiscussionIn the second experiment, the num-bers of nematodes found in the rootsof almost all plants were very low,which might explain why no differ-ences between the infected and non-infected plants could be found.

‘Ngop Lun’, ‘Voi’ and ‘Ngop Cao’ arevery susceptible to P. coffeae. In thefirst experiment, ‘Yangambi Km 5’ and‘Tieu Xanh’ had the lowest number of

nematodes in the roots; but one cannot directly jump to the conclusionthat these genotypes are resistant toP. coffeae, since in the second experi-ment, the number of nematodes foundin the roots of ‘Yangambi Km 5’ did notsignificantly differ from the numberfound in the roots of the highly suscep-tible reference genotype ‘Grand Nain’.In both experiments, this number waslow for almost all plants.

In the first experiment, high num-bers of nematodes in the roots coin-cided with high damage levels and viceversa. The low levels of damage in thesecond experiment can not be attrib-uted to tolerance of the genotypes, butare probably due to the low numbersof nematodes found in the roots of al-most all plants. Only for ‘Ngop Cao’,one can conclude that a significantlyhigher number of nematodes in theroots did not cause any significantdamage.

ConclusionMeloidogyne spp.Infection with Meloidogyne spp. canresult in an increase in the weight ofthe root system and a decrease in thenumber of standing leaves, but furtherresearch is needed. There was never

an effect of infection with Meloidog-yne spp. on the plant height, the shootweight or the girth of the plants.

There is some indication that ‘NguThoc’ might show some resistance toMeloidogyne spp., while ‘Tieu VuaTrang’, ‘Com Chua’ and ‘Ben Tre’ arevery susceptible to Meloidogyne spp.

‘Yangambi Km 5’, ‘Man’, ‘Ngu Thoc’and ‘Tay’ possibly show some toleranceto the gall-forming activity ofMeloidogyne spp, while ‘Voi’ and ‘BenTre’ are highly sensitive to the gall-forming activity of Meloidogyne spp.

P. coffeaeInfection with P. coffeae can result in adecrease in the height of the plantsand the shoot weight, but further re-search is needed. There was never aneffect of infection with P. coffeae onthe weight of the root system, thenumber of standing leaves or the girthof the plants.

‘Ngop Lun’, ‘Voi’ and ‘Ngop Cao’ arevery susceptible to P. coffeae. There issome indication that ‘Yangambi Km 5’and ‘Tieu Xanh’ might show some re-sistance to P. coffeae.

‘Ngop Cao’ and ‘Yangambi Km 5’were the only possible sources of toler-ance found in the experiments.


Table 3. Meloidogyne spp.: results of the damage assessment and nematode reproduction data.

Name Group Percentage of RKG(1) ELF(2) Nematodes Nematodes per dead roots (%) per 10 g of roots root system


‘Tay But’ AA 2.2 a 2.0 ab 4.3 a 7057 a 17036 a

‘Ngu Tien’ AA 0.9 a 1.7 ab 3.6 a 7039 a 21385 a

‘Tieu Mien Nam’ AA 1.5 a 2.2 ab 3.9 a 7813 a 21626 a

‘Tieu Xanh’ AAA 5.4 a 2.4 ab 4.0 a 8579 a 17448 a

‘Tieu Cao’ AAA 2.0 a 2.8 ab 3.6 a 5896 a 21918 a

‘Cao Hong’ AAA 7.4 a 2.6 ab 3.6 a 6552 a 23213 a

‘Xiem Mat’ AAB 2.2 a 2.7 ab 3.5 a 8003 a 30107 a

‘Voi’ AAB 3.1 a 2.9 b 4.5 a 8699 a 26333 a

‘Gao’ ABB 2.0 a 2.8 ab 4.0 a 3676 a 14185 a

‘Ngop Lun’ ABB 2.0 a 2.6 ab 3.9 a 4939 a 15870 a

‘FHIA-23’ AAAA 4.3 a 2.6 ab 3.9 a 5252 a 17688 a

‘Kluai Hom Khom’ AAA 2.2 a 2.3 ab 4.0 a 4213 a 11835 a

‘Yangambi Km 5’ AAA 2.5 a 1.4 a 3.6 a 6707 a 21371 a

Total 2.9 2.4 3.9 6493 19990

Experiment 1999 F G H I J T D

‘Com Lua’ AA 4.5 a 0.8 ab 1.0 a 3320 a 14096 a ab

‘Ngu Thoc’ AA 1.8 a 0.4 a 0.5 a 1431 a 6317 a a

‘Tieu Vua Trang’ AAA 0.0 a 1.5 ab 1.3 a 4368 a 28154 a b

‘Ben Tre’ AAA 0.0 a 1.9 b 1.7 a 4056 a 18630 a b

‘Man’ AAB 0.0 a 0.2 a 0.2 a 2347 a 12020 a ab

‘Com Chua’ AAB 0.0 a 0.6 ab 0.5 a 3052 a 27297 a b

‘Tay’ ABB 0.0 a 0.4 a 0.2 a 1308 a 7252 a ab

‘Ngop Cao’ ABB 0.0 a 1.0 ab 0.5 a 2508 a 14403 a ab

‘Gros Michel’ AAA 0.0 a 0.7 ab 0.8 a 1468 a 7163 a ab

‘Grand Nain’ AAA 0.0 a 0.5 ab 1.0 a 2360 a 9260 a ab

Total 0.7 0.8 0.8 2661 15039A, B, C, F, G, H: Data were not transformed before analysis.

D, E, I, J: Data were log10 (x + 1) transformed before analysis. The untransformed data are presented in the table.

Means in the same column followed by the same letter do not differ significantly according to Tukey (D, E, I, J), Duncan (J) or KW-Bonferroni (A, B, C, F, G, H) for (= 0.05.

(1) = no galling; 1 = trace infections with a few small galls; 2 = < 25 % roots galled; 3 = 25 - 50% roots galled; 4 = 50 - 75% roots galled; 5 = > 75 % roots galled.

(2) = no egg masses; 1 = 1 - 2 egg masses; 2 = 3 - 10 egg masses; 3 = 11 - 30 egg masses; 4 = 31 - 100 egg masses; 5 = > 100 egg masses.

Further research and screening ex-periments are certainly needed. Sincethe numbers of nematodes found in the root system were in general verylow, even on the highly susceptible reference genotype ‘Grand Nain’, research on pathogenicity (reproduc-tive and damage potential) of theP. coffeae population used in the exper-iments might reveal some interestinginformation.

AcknowledgementsFinancial support by the InternationalNetwork for the Improvement of Ba-nana and Plantain (INIBAP), theFlemish Agency for Development Co-operation and Technical Assistance(VVOB), the Flemish InteruniversityCouncil (VL.I.R.) and the AustralianCentre for International Agricultural

Research (ACIAR) is gratefully ac-knowledged. �

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O’ Bannon J.H. & A.L. Taylor. 1968. Migratory en-doparasitic nematodes reared on carrot discs.Phytopathological Notes: 385.

Speijer P.R. & D. De Waele. 1997. Screening ofMusa germplasm for resistance and tolerance tonematodes. INIBAP Technical Guidelines No. 1.INIBAP, Montpellier, France, 42pp.

Stoffelen R. et al. 1999. Screening of Papua NewGuinea bananas to root-lesion and root-knot ne-matodes. INFOMUSA 8 (1): 12-15.

Vinh D.N. & T.D. Quy. 1995. Banana production inVietnam: constraints and potential. Pp. 51-57 inVietnam: banana production, biotechnology anddiversity: Report of an international workshop(George P. et al., eds). Banana ImprovementProject.


D. De Waele works at the Laboratory of Tropical CropImprovement, Catholic University of Leuven (K.U.Leu-ven), K. Mercierlaan 92, 3001 Heverlee, Belgium. The other authors work at the Vietnam AgriculturalScience Institute, Van Dien, Thanh Tri, Hanoi, Vietnam.

Table 4. P. coffeae: general data of the experiments.

Plant height (cm) Shoot weight (g) Root weight (g) Standing leaves Girth (cm)


Not infected with P. coffeae 22.4 b 52.7 b 16.6 a 6.5 a 6.7 a

Infected with P. coffeae 21.3 a 47.2 a 15.4 a 6.4 a 6.5 a

Experiment 1999 F G H I J

Not infected with P. coffeae 30.9 a 124.7 a 57.0 a 5.5 a 8.2 a

Infected with P. coffeae 30.6 a 119.4 a 53.2 a 5.4 a 8.1 aA, B, G, H: Data were square root transformed before analysis. The untransformed data are presented in the table.

C: Data were cube root transformed before analysis. The untransformed data are presented in the table.

F: Data were log10x transformed before analysis. The untransformed data are presented in the table.

D, E, I, J: Data were not transformed before analysis.

Means in the same column followed by the same letter do not differ significantly according to Tukey (A, B, C, F, G, H) or KW-Bonferroni (D, E, I, J) for α= 0.05.

Table 5. P. coffeae: results of the damage assessment and nematode reproduction data.

Name Group Dead roots (%) RNI (%) Nematodes Nematodesper 10 g of roots per root system

Experiment 1998 A B C D

‘Tay But’ AA 1.7 a 1.9 ab 94 ab 114 abc

‘Ngu Tien’ AA 0.9 a 0.6 ab 146 ab 208 abc

‘Tien’ AA 1.8 a 1.9 ab 93 ab 174 abc

‘Tieu Xanh’ AAA 4.5 a 0.3 ab 65 a 69 ab

‘Tieu Cao’ AAA 0.0 a 0.9 ab 129 ab 221 abc

‘Cao Hong’ AAA 0.0 a 0.3 ab 124 ab 313 abc

‘Xiem Mat’ AAB 1.4 a 0.9 ab 344 ab 648 abc

‘Voi’ AAB 7.1 a 12.8 ab 2,297 b 2,894 bc

‘Gao’ ABB 1.7 a 2.2 ab 2,031 ab 3,890 abc

‘Ngop Lun’ ABB 1.0 a 8.7 b 2,840 b 5,027 c

‘FHIA-23’ AAAA 0.7 a 1.7 ab 393 ab 658 abc

‘Kluai Hom Khom’ AAA 0.0 a 1.2 ab 601 ab 577 abc

‘Yangambi Km 5’ AAA 0.0 a 0.1 a 29 a 42 a

Total 1.4 2.3 662 1,093

Experiment 1999 E F G H

‘Tay But’ AA 0.0 a 0.0 a 60 ab 247 ab

‘Com Lua’ AA 0.0 a 0.2 a 28 a 115 a

‘Ngu Thoc’ AA 1.8 a 0.5 a 28 a 153 a

‘Tieu Mien Nam’ AA 0.0 a 0.2 a 16 a 75 a

‘Tieu Vua Trang’ AAA 2.9 a 0.7 a 48 ab 228 ab

‘Cao Hong’ AAA 0.0 a 0.8 a 72 ab 425 ab

‘Man’ AAB 0.0 a 0.0 a 16 a 121 a

‘Com Chua’ AAB 0.0 a 0.3 a 16 a 109 a

‘Ngop Cao’ ABB 0.0 a 0.7 a 534 b 2,886 b

‘Yangambi Km 5’ AAA 3.8 a 0.0 a 12 a 46 a

‘Gros Michel’ AAA 0.0 a 0.0 a 20 a 105 a

‘Grand Nain’ AAA 0.0 a 1.6 a 36 a 118 a

Total 0.7 0.4 75 390

Means in the same column followed by the same letter do not differ significantly according to KW-Bonferroni for α= 0.05.

R. Gomez Kosky, T. Gilliard, L. A. Barranco and M. Reyes

Annual production of bananasand plantains is estimated to beapproximately 88 million tonnes

(FAO 1999), making them one of thelargest food crops in the world afterrice, maize and wheat (INIBAP 1997).

The crop is under serious threatfrom phytosanitary problems such asblack Sigatoka (Mycosphaerella fijiensisMorelet), Panama disease or bananawilt (Fusarium oxysporum f. sp.cubense), the virus diseases bananabunchy top (BBTV-Banana Bunchy TopVirus) and streak mosaic (BSV-BananaStreak Virus) and nematodes, whichcause enormous yield losses. All thisincreases production costs and the de-velopment of new varieties is increas-ingly urgent.

Since 1984, FHIA (Fundación Hon-dureña de Investigación Agrícola)has run a vast programme of researchon hybrids resistant to black Sigatoka.Among these, the cultivar FHIA-18(AAAB) displays tolerance to the dis-ease, good field behaviour and verygood agronomic qualities. It is now oneof the main cultivars grown in Cuba.

The purpose of the work describedhere was the development, within theframework of somatic embryogenesisof banana, of a liquid culture mediumfor the maturation of somatic embryos,for increasing current germinationpercentages and for detecting the ap-pearance of possible somaclonal varia-tions during plant weaning.

Material and methodsPreparation of cell suspensionsThe plant material used consisted of im-mature male flowers from inflores-cences of the hybrid cultivar FHIA-18(AAAB). The latter were collected di-rectly from the plants at a distance ofapproximately 20-30 cm from the last fe-male flower. The male buds were thencut 10 cm from the tip and the bractswere removed to give 3-cm lengthsready for transfer to the laboratory.

The material was disinfected with al-cohol 70% (v/v) for 15 min. Fourteenhands or rows of flowers were then ex-

tracted under a binocular microscopefrom among those closest to the flowermeristem. The 5th to the 12th wereplaced in flasks containing the MA1 in-duction medium proposed by Escalantet al. (1994) for callus formation.

The cell suspensions were initiatedfrom highly embryogenic cultures ofsomatic embryos derived from callusformed in five months from the hands.Medium MA2 proposed by Bieberach(1995) was used for this.

Mass of approximately 150-200 mgfresh weight somatic embryos wereplaced in 25-ml Erlenmeyer flasks con-taining 2 to 3 ml medium. The flasks werethen placed on an orbital agitator at 90rpm at 27°C in continuous darkness.

The cell suspension formed was fil-tered on 500µm metal filters after 15days. The different studies performedduring this work were performed onthese cell suspension filtrates.

Subculturing was performed every15 days in conformity with the protocoldeveloped by Escalant et al. (1994).Cell growth was evaluated by the sedi-mented cell volume method proposedby Schoof (1997). For this, 15-mlaliquots of cell suspension were placedin 15-ml graduated conical tubes. Thevolume of sedimented cells was mea-sured after sedimentation for 5 min. Ateach subculture, the final cell concen-tration was adjusted to 3% indepen-dently of total capacity of the Erlen-meyer flask used.

Formation of somatic embryosSomatic embryos were obtained onmodified Schenck and Hildebrandt’smedium (1962): SH mineral salts;Murashige and Skoog vitamins (1962),malt extract 100 mg/l, L-glutamine 100mg/l, L-proline 230 mg/l, naphthale-neacetic acid (ANA) 0.2 mg/l, kinetin0,05 mg/l, lactose 10 g/l, zeatin 0.05mg/l, sucrose 45 g/l, pH 5.3.

The influence of the initial concen-tration on the formation of somaticembryos was studied by testing fourcell cluster fresh weights (50, 100, 250and 500 mg) for 25 ml medium. Thenumber of embryos formed was evalu-ated after 15 and 30 days of culture bytaking several 1-ml cell suspensionsamples after agitation of the flasks for

several seconds. Several repetitionsper test were performed in 250-ml Er-lenmeyer flasks under culture condi-tions identical to those described inthe preceding paragraph.

Secondary multiplication of somaticembryosThe purpose of the experiment was todetermine the effect of initial inocula-tion density on the secondary multipli-cation of somatic embryos in agitatedliquid medium. A basic MS medium wasused, complemented with 0.3 mg 6-ben-zylaminopurine (6-BAP), 1 mg in-dolacetic acid (AIA), 3% sucrose, withpH 5.3 before autoclaving. Inoculationdensities of 0.2, 0.4 and 0.6 g freshweight somatic embryos at the globularstage were tested in 25 ml medium withfive repetitions in 250-ml Erlenmeyerflasks. The different tests were weighedon an analytical balance on day 60 ofculture. The number of embryos formedwas evaluated by placing several 1 gfresh weight samples of somatic em-bryos in Petri dishes 5 cm in diametercontaining a water-Phytagel mixture.Counting was performed under a binoc-ular microscope after solidification ofthe mixture. The embryos were alsomeasured with a graduated rule on thereverse side of the dish.

Maturation of somatic embryosThree different concentrations weretested for the maturation of the so-matic embryos obtained: 400, 800 and1,000 mg fresh weight of somatic em-bryos at globular stage for 30 ml modi-fied Murashige and Skoog medium(1962): MS salts, MS vitamins, biotin1.0 mg/l, 6-BAP 0.5 mg/l, AIA 2.0 mg/l,sucrose 45 mg/l, pH 5.8 in 250 ml Er-lenmeyer flasks agitated at 90 rpm,27°C in continuous darkness.

Maturation was evaluated weekly.Samples were taken for this and ob-served under a binocular microscope.The moment at which the embryosreached maturity was detected by ob-servation of the changes in their mor-phology.

GerminationThe different tests described belowwere performed with 500 ml RITA tem-


Improvement Cell culture techniques

Somatic embryogenesis in liquid media. Maturationand enhancement of germination of the hybridcultivar FHIA-18 (AAAB)

porary immersion systems each con-taining 200 ml liquid medium. Theywere kept in phytotrons at 25°C ± in40 µM.m-2.s-1 fluorescent light with a16-hour photoperiod and an immersionfrequency of 1 min 3 times a day (Es-calant et al. 1994).

Germination of mature somatic em-bryos was performed using the threeprocedures below.

The effect of Biobras-6 (an equivalent of brassinosteroid) on germination in semi-solid medium

The five following treatments wereapplied:Treatment Description

T1 Control (germination medium, Escalant et al.1994)

T2 6-BAP + AIA + 0.005 mg/l Biobras-6

T3 6-BAP + AIA + 0.010 mg/l Biobras-6

T4 0.005 mg/l Biobras-6

T5 0.010 mg/l Biobras-6

Twenty embryos were placed in cul-ture flasks containing 30 ml mediumand kept in a growth chamber withsolar light at 50 to 62.5 µM.m-2.s-1 andat 27°C ± 2°C. Samples were chosen atrandom with 15 repetitions per treat-ment. The numbers of embryos thathad formed complete plantlets werecounted after 45 days of culture.

The effect of Biobras-6 on germination inRITA temporary immersion systemsThe effects of two Biobras-6 concen-trations (0.005 and 0.01 mg/l) weretested with the same initial embryo in-oculation density (0.5 g).

The effect of the initial somatic embryoinoculum density on germinationFour initial concentrations were stud-ied in the third protocol: 0.3, 0.5, 0.7and 1.0 g somatic embryos in a basicMS medium complemented with 0.5mg/l 6-BAP, 2.0 mg/l AIA and the bestBiobras-6 concentration found in thepreceding experiment. Three RITAwere used per treatment, containingMS medium (1962) complementedwith 0.5 mg/l 6-BAP, 2.0 mg/l AIA and30 g/l sucrose, with pH 5.8.

The experiments were controlled atthe same time by preparing 250 mlglass jars containing 20 somatic em-bryos and 30 ml semi-solid medium(Phytagel 2 g/l) of the same composi-tion as that of the RITA preparations.Twelve repetitions were performedunder the same culture conditions. Allthe jars and RITA preparations wereplaced on shelves in a growth chamberunder 50-62.5 µM.m-2.s-1 solar light andat 27°C ± 2°C. The initiation of germi-nation was evaluated in both experi-

ments after Day 7 of culture and thetotal number of plantlets formed pertreatment was counted after 40 days.

As soon as plantlets appeared in theRITA preparations they were trans-ferred to 250 ml culture flasks contain-ing 30 ml medium containing MS saltsand 3% sucrose solidified by 6 g/l agarand with pH 5.8 before autoclaving.This was performed so that they couldcontinue growth for a further month ina culture chamber under natural light.

Comparative morphological study ofplants prepared by organogenesis orsomatic embryogenesisPlantlets 4 to 5 cm tall prepared by so-matic embryogenesis were weaned byplanting in 50-cavity polyurethane traysin artificial substrate consisting of amixture of casting and zeolite (3:1).They were watered by micro sprinklingfor 2 min three times a day. Anotherbatch of 200 plants obtained by in vitroculture of axillary buds was planted atthe same time. The following quantita-tive characters were observed in 50plants chosen at random in the twobatches after 50 days: plant height,length and breadth of leaf 2, petiolelength, distance between leaves 2 and 3and survival percentage. Qualitativecharacters such as pseudostem and leaflamina colour were also observed.

Results and discussionCell suspensionsEmbryogenic cell suspensions of thehybrid cultivar FHIA-18 (AAAB) weregenerated using somatic embryos atthe globular stage as the initial ex-plant. The formation of proembryosand of small, spherical embryogeniccells with dense cytoplasm containingstarch grains were observed on Day 10of the cell suspension cultures.

Similar observations were reportedby Cote et al. (1996) for cell suspen-

sions prepared from male flowers ofthe ‘Grande naine’cultivar (AAA). Inthe multiplication phase, these sus-pensions were formed of a great num-ber of actively dividing isolated spheri-cal cells and heterogeneous, irregularcell masses that were translucid ornot. This also agrees with the observa-tions made by De Vries et al. (1996) oncell suspensions of carrot. The cellcharacteristics above are consideredto be an indicator of the embryogeniccondition of the cell suspension(Williams and Maheswaram 1986).Other studies of Musa cell suspensionshave confirmed the presence of pro-tein bodies and starch in cells in em-bryogenic masses (Sannasgala 1989,Bieberach 1995).

The cell suspensions displayedchanges in composition during thefirst two months of culture. The quan-tity of cell masses increased while thatof isolated cells decreased to practi-cally negligible levels. These embryo-genic masses varied in size from 80 to300 µm and finally formed 80 to 95% ofthe cell suspensions.

The suspensions in this culturemedium also acquired a thick consis-tency directly related to thecell:medium volume balance.

Formation of somatic embryosGranular structures consisting ofproembryos and somatic embryos atthe globular stage began to appear atthe bottom of the Erlenmeyer flasksfrom Day 15 of culture onwards. Analy-sis of the results of the different inocu-lation densities tested for somatic em-bryo formation in liquid mediumrevealed significant differences be-tween the different treatments onboth Day 15 and Day 30 of culture.

The best results were obtained witha density of 100 mg/25ml in which1883 globular stage somatic embryos


Figure 1. Influence of inoculum density on the formation of somatic embryos of the cultivar FHIA- 18(AAAB) after 15 and 30 days of culture.*different letters represent significant differences with the Duncan test, p<0.005%

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formed per ml suspension in 30 days(Figure 1).

Other authors have observed evenbetter results for the number of so-matic embryos formed but on differentcultivars and placing 1 ml cell suspen-sion in a semi-solid medium (Bieber-ach 1995, Cote et al. 1996, Grapin et al.1998).

The diameter of the somatic embryosobtained from cell suspensions of FHIA-18 varied from 0.5 to 1.2 mm, i.e. an av-erage of 0.86 ± 0.25 mm. Their weightvaried from 0.65 to 0.90 mg dependingon the stage of development, i.e. an av-erage of 0.73 ± 0.16 mg. Bieberach(1995) described very similar results butfor other banana cultivars.

Secondary multiplication of somaticembryos

It was verified that the initial con-centration does have an effect on themultiplication of somatic embryos inmodified MS medium as significant dif-ferences between the different treat-ments appeared both in fresh weightand in the number of embryos afterculture for 60 days. With an initial con-centration of 0.6 g:25 ml medium, theincrease in fresh weight was x 42 in 60days with the formation of a greaternumber of complete embryos (Table 1).This was the fist time that this hadbeen achieved with banana in liquidmedium under agitation.

It should be noted that the matura-tion of somatic embryos was enhancedat a lower density (0.2 g:25 ml), butthat there was little multiplication.Once again, it is unnecessary todemonstrate the importance of deter-mining an inoculation concentrationadapted to each stage in the embryo-genesis process.

It is important to stress that cascadeembryogenesis may occur in the ab-sence of exogenous auxin; this is re-ferred to as auto embryogenesis, prolif-eration or mass propagation (Meckleet al. 1995). The embryos at the globu-lar stage display cascade multiplica-tion, each forming four to six new so-matic embryos, and so on. Somaticembryos can form from the epidermalcells of the first embryo (Escalant etal. 1994). The process can continue in-definitely, thus enabling the multipli-cation of somatic embryos in bioreac-tors instead of using cell suspensions.

Gómez et al. (2000, in press)achieved cascade multiplication of so-matic embryos of the cultivar Grandenaine (AAA) in agitated liquidmedium. These authors found that thelowest density of somatic embryos wasthe most effective: 0.1 g. This confirmsthe influence of the genotype in the in

vitro processes and indicates the needfor the development of methods suitedto each cultivar studied.

Escalant et al. (1994) were the firstto perform the secondary multiplica-tion of somatic embryos of the cultivarGrande naine (AAA), but in a tempo-rary immersion system. Their multipli-cation coefficients are very similar tothose reported here. However, theyreached the same level after a muchlonger period (six months).

Maturation of somatic embryosTwo of the initial densities studiedgave good results in this experiment inagitated liquid medium. Maturation ofsomatic embryos was rapid at a densityof 800 mg, taking only 15 days and with30% embryos reaching full maturity.However, the synchronisation of matu-ration was better at a density of 400mg since 70% of the embryos reachedmaturity, but later since this took 22 days.

No maturation occurred at density1000 mg and most of the embryos re-mained at the globular stage. Thisshows the close relation between ini-tial embryo density and the matura-tion process. It also shows that there isgreater accumulation of reserve sub-stances and less multiplication whenlow densities of some 400 mg are used,as is the case here. This phenomenonis not mentioned in the literature con-sulted since once they have formed,the somatic embryos at the globularstage are subcultured immediately onto a germination medium where lowsuccess rates are achieved, with alonger latency period.

GerminationThe effect of Biobras-6 in semi-solid cul-ture mediumIt was observed in this first experi-ment that the largest quantity of em-

bryos germinated in treatments T2and T3 combining Biobras-6, AIA and6-BAP, as these treatments displayedsignificant differences in comparisonwith the other treatments and thecontrol. Their germination percent-ages were 37 and 41% respectively.These results demonstrate the stimu-lating effect of Biobras-6 on germina-tion (Table 2) when this acts in syn-ergy with the mixture of regulatorsaimed at enhancing germination. Thebest treatment is T3, where 0.01 mg/lBiobras-6 was added. Work on calloge-nesis by Rayas et al. (1999) showsthat DAA-6 (Biobras-6) and MH-5, twosubstances similar to brassinosteroid,also had a favourable effect on callusgrowth and quality, in particular withconcentrations of 0.01 mg/l Biobras-6and 0.1 mg/l MH-5. Comparison of thegermination of somatic embryos insemi-solid medium with that in a tem-porary immersion system shows thatthe latter process is more effectivewith regard to both latency time andgermination percentage.

The effect of Biobras-6 on the germina-tion of somatic embryos with the RITAtemporary immersion systemThe results of this second experiment,in which somatic embryos were set togerminate using the RITA temporaryimmersion system, reveal a higher ger-mination percentage and significantdifferences to the other treatmentswhen a Biobras-6 concentration of 0.01mg/l was used. The number of embryosthat germinated in this treatment at-tained 600, making a germination per-centage of 85%, which is 15% higherthan that achieved without Biobras-6(Figure 2).

The use of Biobras-6 in in vitro cul-ture has already given good results forthe germination of papaya somatic em-bryos (Posada 1995). According to


Table 1. The effect of the initial inoculation density on the multiplication of somaticembryos of the hybrid cultivar FHIA-18 (AAAB) on Day 60 of culture.

Inoculation density (g/l) Total number of somatic embryos Fresh weight (g)

0.2 1 200 d* 18.65 d

0.4 4 550 c 15.50 c

0.6 16 680 a 25.00 a

0.8 9 450 b 12.35 b*different letters indicate significant differences in Dunett’s (C) proof at p < 0.05%.

Table 2. The effect of Biobras-6 on the germination of somatic embryos in semi-solid medium.

Treatment Description Number of Percentage ofgerminated embryos germination

T1 Control 80 27 cd*

T2 6-BAP+AIA+0.005 mg/l Biobras-6 107 37 b

T3 6-BAP+AIA+0.010 mg/l Biobras-6 122 41 a

T4 0.005 mg/l Biobras-6 100 33 c

T5 0.010 mg/l Biobras-6 100 33 c*different letters indicate statistically significant differences for P<5%.

Nuñez (1996), brassinosteroids displaystrong synergy with auxins. They canalso act with gibberellins either asauxins or as gibberellins or cytokinins.

Comparison of the temporary im-mersion system with the precedingtest on semi-solid medium shows thattemporary immersion combined withthe regulatory action of Biobras re-sulted in a positive improvement of theontogenesis of somatic embryos.

Indeed, bud formation is one of themajor difficulties in the somatic em-bryogenesis of many species, includingconifers (Tautorus et al. 1992, Lelu etal. 1994) and rubber tree (Michaux-Ferrière et al. 1992, Etienne et al.1997). This obstacle can be overcomeby the use of temporary immersion sys-tems. The positive impact of this typeof treatment seems to be related to theway in which the liquid medium isused. Indeed, it combines the advan-tages of permanent immersion, avoid-ing the problems of vitrification andlack of oxygen, and those of partial im-mersion on inert support (Roberts andSmith 1990) by mitigating absorptioninefficiency and reducing handling op-erations.

In temporary immersion systems, theentire surface of the plant material is inuniform contact with the nutrients ofthe medium, even when it is not im-mersed since a fine coating of mediumadheres to the plant tissue by capillaryattraction. This coating is insufficient toinhibit gas exchanges and the chemicalcomposition is renewed at each immer-sion. Aeration is also improved as eachimmersion also regenerates the ambientmedium (Teisson and Alvard 1995). Inaddition, short agitation of the plant ma-terial occurs. All these features have en-abled the germination of somatic em-bryos of various species (Citrus, Musa,Coffeae) that was hitherto impossible inErlenmeyer flasks or bioreactors (Teis-son and Alvard 1995), as the latter aremore complex, more difficult to handleand more expensive than RITA (Etienneet al. 1997).

It should be noted that the use ofRITA systems has also made it possibleto prevent the oxidation of somatic em-bryos of the cultivar FHIA-18 (AAAB).Bieberach (1995) reports similar resultson other cultivars, most of whose so-matic embryos started to germinate onDay 7 of culture. The same phenomenonhas also been observed with other tem-porary immersion systems consisting of10 l recipients (Nalgène company) inwhich 65.5 to 73% of embryos (500 to800 per recipient) germinated (Gómez,unpublished data).

Temporary immersion systems thusenhance more substantial, synchronised

development of somatic embryos, alsodescribed by Etienne et al. (1997) onHevea brasiliensis (Mull Arg) and byCabasson et al. (1997) on Citrus deli-ciosa (Ten).

The effect of the initial inoculation den-sity of somatic embryos on germinationin the RITA temporary immersion systemThe best density is 0.5 g, at which thebest germination percentage (85%)was observed. The percentages are farhigher than that of the control in allcases (Table 3). They are some of thehighest figures ever attained for thegermination of somatic embryos of ba-nana and plantain. This may be the re-sult of various factors, including thepositive effects of temporary immer-sion and the previously describedfavourable effects of the regulator Bio-bras-6 and, of course, the genotype. Nospecific information has hitherto beenreported concerning the germinationof somatic embryos of the hybrid culti-var FHIA-18 (AAAB).

Known germination percentages ofsomatic embryos of the genus Musavary between 0.45 and 80% accordingto the genotype and the culturemedium (Bieberach 1995, Cote et al.1996, Schoof 1997, Grapin et al. 1998).

The highest germination percent-ages obtained to date are those of Es-calant et al. (1994), who also usedtemporary immersion systems but onother banana cultivars.

Comparative morphological study ofplants resulting from organogenesis andthose being weaned after somaticembryogenesisThe results do not show any differ-ences between the two batches of

plants produced by organogenesis orsomatic embryogenesis except in thelarger size of those of embryogenic ori-gin (Table 4). In addition, no off-types,such as dwarf, giant or mosaic vari-ants, were observed (Sandoval et al.1997). These results agree with thoseof Cote et al. (1999) who worked oncell suspensions of the cultivar Grandenaine (AAA) and compared plants pro-duced using this technique with thoseproduced by traditional organogenesis;they did not find any morphologicaldifferences in the field.

This does not mean that there wereno somaclonal variations, but simplythat it was not possible to detect themat this stage of development. Sandovalet al. (1997) pointed out that in anycase at this stage it is only possible todetect approximately 60% of so-maclonal variations. They thereforesuggest that field evaluation should becontinued to cover the developmentcycle for several generations. In addi-tion, Schoof (1999) reported up to 97%somaclonal variations in‘Williams’plants produced from cell


*different letters indicate statistically significant differencesfor P<5%.

Table 3. Effect of the initial inoculation density on the germination of somaticembryos of the hybrid cultivar FHIA-18 (AAAB) on Day 30 of culture.

Inoculation Initial number of Number of Percentage of density (g) embryos germinated embryos germination

(X+ ET)

0.3 750 320 ±14.1 45 b*

0.5 750 600 ±16.7 85 a

0.7 1 050 402 ±14.3 26 bc

1.0 1 500 260 ±12.3 17 c

Control 300 43 ±7.71 14 c*different letters indicate significant differences in Dunett’s (C) proof at p < 0.05%.

Figure 2. The effect of Biobras-6 on thegermination of somatic embryos in the RITAtemporary immersion system.

Table 4. Comparison of plants of the hybrid cultivar FHIA-18 (AAAB) obtainedeither by somatic embryogenesis or by organogenesis.

Type of Petiole Length Width Distance Plant morphogenesis length of leaf 2 of leaf 2 between height

(cm) (cm) (cm) leaves (cm)2 and 3 (cm)

Organogenesis(axillary buds) 1.95± 0.19 a* 13.22± 0.7 a 6.68± 0.6 a 1.90± 0.2 a 6.60± 0.4 b

Somatic embryogenesis 1.86± 0.12 a 13.90±. 62 a 7.10± 0.4 a 1.91± 0.2 a7.30± 0.6 a

Average ± ET 1.90 ± 0.15 13.55 ± 0.67 6.90 ± 0.53 1.9 ± 0.2 6.95 ± 0.54

CV 0.13 0.21 0.13 0.15 0.3*Different letters represent significant differences at P< 5%.

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I. Bermúdez, P. Orellana P., J. Pérez Ponce, J. Clavero, N. Veitía,

C. Romero, R. Mujica and L. García R.

Black Sigatoka (Mycosphaerellafijiensis Morelet) is currentlythe most destructive disease in

the world for bananas and plantains.

Since it appeared in Cuba inNovember 1990, it has become themost widespread fungal disease in theplantations in the island.

The best solution for reducing thedamage caused by this devastating dis-ease is the breeding of resistant vari-eties. Since 1984, the FHIA (Fun-dación Hondureña de InvestigaciónAgrícola) has developed a vast re-

search programme on resistant hy-brids, which include ‘French Plantain’FHIA-21 (AAAB), which is resistant towilt, gives fruits of good size and qual-ity enabling good yields, but whosehabit is too tall.

The use of mutagenic agents com-bined with biotechnology techniquesmakes it possible to intensify geneticvariability in order to improve certain

suspensions; the variations apparentlyresulted from the «scalp» technique inwhich very strong 6-BAP concentra-tions are used. Research at the Labo-ratory Tropical Crops Improvement atCatholic University of Leuven (KUL)showed 100% somaclonal variation inplants produced from cell suspensionsof the cultivar Grande naine (AAA);the most common variations after 6months were dwarfism and thick, dis-torted leaves (INIBAP 1997).

AcknowledgementsThe authors thank Dr Jean-Vincent Es-calant for revising this work. �

ReferencesBieberach C. 1995. Embriogenésis somática y regen-

eración de plantas en cultivares de Musa sp. Tesispara optar al grado de Magister Scientiae. CATIE,Turrialba, Costa Rica. 84 pp.

Cabasson C., D. Alvard, D. Dambier, P. Ollitrault & C.Teisson. 1997. Improvement of citrus somatic em-bryo development by temporary immersion. PlantCell Tissue and Organ Culture 50: 33-37.

Cote F., R. Domergue, S. Monmarson, J. Schwendi-man, C. Teisson & J.V. Escalant. 1996. Embryo-genic cell suspensions from the male flower ofMusa AAA cv. Grand Naine. Physiologia Plan-tarum 97: 285-290.

Cote F., R. Domergue, M. Felliot & C. Dubois. 1999.Performance au champ de plants de bananiersissus de suspensions cellulaires embryogènes(Musa AAA cv. Grande Naine). INFOMUSA8(1):XII.

De Vries S.C., H. Booij, J. Cordewener, F.A. Van An-gelen, A. De Jong, A. Van Kammen, F. Loschiavo,G. Schellekens, P. Sterk & H. Terzi. 1996. Develop-mental mutants and extracellular proteins in car-rot somatic embryogenesis. Pp. 22-23 in ADEBIO,International Symposium of Biotechnology forMajor Crops.

Escalant J.V., C. Teisson & F. Cote. 1994. Amplifiedsomatic embryogenesis from male flowers oftriploid banana and plantain cultivars (Musaspp.). In Vitro Plant Cell. and Dev. Biol. 30: 181-186.

Etienne H., N. Lartaud, M. Michaux-Ferriere, P. Car-ron, M. Berthouly & C. Teisson. 1997. Improve-ment of somatic embryogenesis in Heveabrasiliensis (Mull. Arg.) using the Temporary Im-mersion Technique. In Vitro Plant Cell. and Dev.Biol. 33: 81 87.

FAO.1999. Boletín Trimestral de Estadística. 12(34).Grapin A., J.L. Ortíz, R. Domergue, J. Babeau, S.

Monmarson, J.V. Escalant, C. Teisson & F. Cote.1998. Establishment of embryogenic callus andinitiation and regeneration of embryogenic cellsuspensions from female and male imature flow-ers of Musa. INFOMUSA 7(1): 13-15.

Gómez R., J.V. Escalant, M. Reyes, L. Posada & M.Freire. 2000. Embriogénesis somática en mediolíquido en Musa (AAA) cv. Gran Enano. COR-BANA (in press).

INIBAP 1997. Annual report. International Networkfor the Improvement of Banana and Plantain.Montpellier, France.

Lelu et al.1994. An improved method for somaticplantlet production hybrid lanch (Larix X lep-toeuropaea) in somatic embryo maturation. Part1. Plant Cell Tissue Organ. Cult. 36: 07-115.

Michaux-Ferriere N. & J. Schwendiman. 1992. His-tology of somatic embryogenesis. Pp. 247-259 inReproductive Biology and Plant Breeding (Y.Dattée, C. Dumas & A. Gallais, eds). Springer-Verlag, Berlin.

Merkle S.A., W.A. Parrott & B.S. Flinn. 1995. Mor-phogenic aspects of somatic embryogenesis. pp.155-203 in In vitro Embryogenesis in Plant (T.A.Thorpe, ed.). Kluwer Academic Publishers, Dor-drecht, Netherlands.

Murashige T. & F. Skoog. 1962. A revised mediumfor rapid growth and bio assays with tobacco tis-sue cultures. Physiologia Plantarum 15: 473-497.

Nuñez V.M. 1996. Los brasinoesteroides y su activi-dad biológica. INCA. La Habana, Cuba.

Posada L. 1995. Desarrollo de la embriogénesissomática en la Fruta Bomba (Carica papaya L.).Trabajo de diploma. Universidad Central de LasVillas. 47pp.

Rayas A., M. García & R. Landa. 1999. Efecto delBiobras-6 en la organogénesis la malanga (Xan-thosoma spp.). Libro de resúmenes cortos, V°Coloquio Internacional de Biotecnología Vegetal.Ediciones GEO, La Habana, Cuba.

Roberts A.V. & E.F. Smith.1990. The preparation invitro of chrysanthemum for transplantation tosoil. I. Protection of roots by cellulose plugs.Plant Cell Tissue Organ Cult. 21: 129-132.

Sandoval J.A., L. Pérez & F. Cote. 1997. Estudiomorfológico y de la estabilidad genética de plan-tas variantes de banano (Musa AAA cv. GranEnano).Etapas de cultivo in vitro, aclimatación ycampo. CORBANA 22(48): 41-60.

Sannasgala K. 1989. In vitro somatic embryogenesisin Musa. Ph.D. thesis, K.U.Leuven, Belgium189pp.

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Schoofs H., B. Panis, H. Strosse, A. Moyo, J. Lopez,N. Roux, J. Colezel & R. Swennen. 1999. Bottle-necks in the generation and maintenance of mor-phogenic banana cell suspensions and plant re-generation via somatic embryogenesis therefrom.INFOMUSA 8(2): 3-7

Tautorus T.E., M.M. Lulsdorf, S.I. Kikcio & D.I. Dun-stan. 1992. Bioreactor culture of Picea marianaMill. and the species complex Picea glauca-en-gelmannii somatic embryos. Growth parameters.Appl. Microbiol. Biotechnol. 38: 46-51.

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Rafael Gomez Kosky and Maritza Reyes work atthe Instituto de Biotecnología de las Plantas, Universi-dad Central de Las Villas, Santa Clara, Cuba, email:[email protected]; Terrence Gilliard at theMinisterio de Agricultura de Santa Lucia and Luis Antonio Barranco at the Universidad de LasTunas, Las Tunas, Cuba.

Improvement Induced variability

Improvement of the hybrid plantain clone FHIA-21 by mutagenesis in vitro

agronomic characters such as fructifi-cation, yield, quality and resistance topathogens and diseases (Ho et al.1993, 1994). In addition, tissue culturetechniques facilitate the induction,breeding and dissemination of mu-tants.

In vitro shoot tip culture has beenused to induce mutations in severalMusa genotypes with different ploidylevels and different combinations ofgenomes of acuminata (A) and bal-bisiana (B) (Novak et al. 1986).

The work presented here was per-formed within the framework ofbiotechnology applied to genetic im-provement, with the following objec-tives:• the breeding of short stature so-

maclonal variants among irradiatedpopulations of the clone FHIA-21,

• the study of behaviour with regard toblack Sigatoka.

Material and methodsGermplasm was delivered to the labo-ratory for subsequent in vitro multi-pl ication using the protocol de-scribed by Orellana et al. (1991). Theformation of multiple buds was in-duced by placing shoot tips in an MSmedium (1962) complemented by 6-benzyl aminopurine (6-BAP) 20 mg/l,indolacetic acid (AIA) 0.65 mg/l andsucrose 30 g/l at pH 5.8. To inducevariability, the buds were subjectedto 25 Gy gamma radiation derivedfrom the disintegration of C60. Fivesubcultures were then performed toregenerate approximately 10,000 tis-sue culture plants that were hard-ened off in the greenhouse for 45days before being transplanted in thefield at Remedios experimental sta-tion. Minimum agricultural work wasperformed throughout the develop-ment of the plantation, without theapplication of fungicides, so that theresponse of plants to natural pres-sures could be observed.

Evaluations consisted of selectingplants with positive characters in thefield and studying the variability of thepopulation. Records were made ofplant height (with three categories),pseudostem girth, total leaves, thenumber of spotted (BS) leaves atbunch formation and then at harvest-ing, the number of hands and fingersof the bunches (three categories) andthe length of the central finger of thesecond and penultimate hands. Thelines with positive characteristics wereplanted at five plants per row at thesame experimental station to performa clone study with comparison withthe original clone. The most promisinglines were transferred in vitro in order

to increase the population for study inother environments.

The work was performed as in the di-agram below (Figure 1):

Results and discussionEvaluation revealed considerable vari-ability in the plant material with re-gard to plant height, pseudostem di-ameter, total number of leaves,changes in bunch level and impact ofBlack Sigatoka, clearly showing the ef-fectiveness of the combination of mu-tagen and tissue culture. Novak et al.(1990) obtained similar results in animprovement programme with muta-tion of clones of the genus Musa.

A high degree of variation in plantheight was observed in particular, as isshown in Table 1:

The results in Table 1 show that theenvironment has a marked influenceon both populations. Indeed, the nor-mal height of the original clone FHIA-21 varies from 250 to 300 cm in thefirst reproduction cycle. In addition,

the smallest plants in the irradiatedbatch included several variants withother favourable changes such as fin-ger size, bunch shape and leaf struc-ture that differ considerably from theoriginal clone. The aim of this workwas not only to seek low plants butalso to take into account all the otherpositive characters since the frequen-cies of variation in height were verysimilar on both the selected and non-selected irradiated batches. It is alsoimportant to underline that in the firstcycle, many banana and plantainclones do not attain the heightreached in subsequent cycles.

Considerable variation in the num-ber of fingers was also noted (Table 2)in the entire population in which59.86% of plants bore bunches withover 60 fingers. This frequency wasmaintained in the selected plants(57.1%).

Many authors have noticed that thefrequency of phenotypic and/or mor-phological variations (plant height,


Establishment of shoot tips of the original clone FHIA-21: 2 months

Formation of adventitious buds (multiple buds): 2 months

Mutagenic treatment of adventitious buds

4 or 5 subcultures to eliminate possible chimeras: 3 months

Regeneration and rooting of tissue culture plants: 2 months

Hardening off in the greenhouse: 2 months

Transplantation and growth of tissue culture plants in the field:

11 to 16 months (mother plant)

- Clonal study = 24 months

- Repetition of the experiment

- Field validation

Figure 1. Diagram of the improvement of the hybrid FHIA-21 by mutation.

Table 1. Variation in plant height during the first reproduction cycle.

Height categories (cm) Number of plants selected Frequency of variation (%)

Selected irradiated material

100-250 41 38.30

251-300 61 57.00

>300 5 4.70

Total 107 100.00

Non-selected irradiated material

100-250 103 35.76

251-300 169 58.68

>300 6 5.55

Total 288 100.00

leaf colour), physiological variations(growth and sucker multiplication, du-ration of flowering, fruit ripening) andagronomic variations (bunch quali-ties) varies from 3 to 40% in the firstgeneration plants according to theirgenotype and the radiation doses ap-plied (Novak et al. 1990).

Phenotypic variation frequency inthe 1024 first plants observed was4.78%. They reveal four somaclonalvariants that could be the False Horntype, although two of them are suscep-tible to black Sigatoka (Table 3).

Comparison of the average valuesand the deviations between the ob-servations of the selected populationand those of the total populationshows that the latter is taller thanthe selected population (Table 4). Incontrast, an average of about sixhands per bunch was observed in

both cases. The plants also had an av-erage of more than 60 fingers perbunch in most cases. This confirmsthe positive correlation betweenplant height and the total number offingers per bunch.

Analysis of population deviationsshows that the most variable parame-ters are height and number of fingers,as has already been reported.

Five of the selected plants displaythe best profile with a combination ofdifferent characters (Table 5) and var-ied reactions to black Sigatoka.

Significant differences in plantheight were observed between thelines themselves and also between thelines and the original clone FHIA-21.Lines IBP 24-14 and IBP 47-4 displaythe lowest values. However, the latteralso have poorer results than the otherlines and the control with regard to

several important agronomic charac-ters (number of fingers per bunch,bunch weight). In addition, theirbunches are of the False Horn typewhereas those of the others and thecontrol have French type bunches. Incontrast, lines IBP 14-23 and IBP 17-13, whose heights are significantlylower than the control FHIA-21, dis-play good agronomic behaviour in theother yield indicators. This makesthem very promising for the selectionof short plants in this hybrid.

It should be stressed that the con-trol FHIA-21 suffered a strong gener-alised black Sigatoka attack and couldnot produce completely developed fin-gers, which is in contradiction with re-ports that concluded that it has highresistance (Cote et al. 1994).

ConclusionsThe general frequency of variation ofirradiated hybrid FHIA-21 materialwas 4.78% during the first cycle(mother plant). The most variablecharacters are plant height and thenumber of fingers per bunch, amongother morphological variations. Themost stable characters are pseudostemdiameter and the number of hands perbunch.

Although the hybrid FHIA-21 bears aFrench type bunch, several variantswere observed that produced FalseHorn type bunches whose general mor-phology is very different to the originalclone.

Most of the population studied wasstrongly affected by black Sigatokaeven though plants that had reachedharvest with more than three activeleaves were selected. �

ReferencesCote F., F. Rosales, P. Rowe & C. Rivera. 1994. Reac-

ción a Sigatoka negra y comportamientoagronómico de plátanos híbridos (AAAB) someti-dos a desmane. Pp. 339-405 in Memorias XI Re-unión ACORBAT, San José, Costa Rica.

Ho Y.W., Y.P. Tan & C. Mak. 1993. Micropropagationfor commercial production of plantings materialswith special reference to banana. In Proceedings


Table 2. Variation in the number of fingers per bunch during the first cycle.

Variation in the number of fingers Number of plants Frequency (%)

Selected irradiated material

up to 40 fingers 21 20.00

41 to 60 fingers 24 22.80

over 60 fingers 60 57.10

Non-selected irradiated material

up to 40 fingers 16 10.08

from 41 to 60 fingers 43 29.25

over 60 fingers 88 59.86

Table 3. Phenotypic variations observed in comparison with the original clone inplants selected during the first cycle.

Number Low habit; Longest Short, Small, High Total of plants False Horn fingers slender straight resistance frequency observed type fingers fingers to black (%)

possible Sigatoka

1024 4 10 20 12 3 4.78

Table 4. Average and deviations between observations according to thepopulation.

Average Deviation

Population Height Pseudo- Number Number Height Pseudo- Number Number (cm) stem of hands of fingers (cm) stem of hands of fingers

girth (cm) girth (cm)

Non-selected irradiated material 270.71 48.48 6.61 68.78 25.40 6.29 6.19 18.83

Selected irradiated material 250.44 47.91 6.40 67.59 25.94 5.25 1.04 20.78

Table 5. Growth parameters evaluated in the selected lines.

Code of Plant Pseudo TLF* TLH** Planting Number of Bunch Girth of External length the line height stem girth to harvest fingers weight central finger*** of central

(cm) (cm) (months) (kg) (cm) finger (cm)

IBP 14-23 281.6b 54.2a 12.0a 6.2b 11.6c 83.2b 14.08b 3.4a 22.8a

IBP 17-13 282.5b 47.5b 10.5ab 9.0a 13.0a 64.0c 14.5b 2.75bc 20.0a

IBP 50-5 294.8ab 57.4a 11.4ab 4.6b 11.6c 100.0a 21.08a 3.40a 23.6a

IBP 24-14 236.0c 45.4b 9.4b 5.0b 13.0a 45.0d 5.15c 3.1abc 19.6a

IBP 47-4 215.0d 36.8c 7.0c 4.4b 12.8ab 57.2cd 5.98c 2.62c 19.6a

(FHIA-21) Control 302.8a 56.6a 9.8ab 6.6b 11.8bc 105a 13.8b 3.32ab 22.0a

Deviation (x) ±0.26 ±0.14 ±0.67 ±0.69 ±0.30 ±0.69 ±0.45 ±0.16 ±0.90

* TLF: Total leaves at flowering ; ** TLH: Total leaves at harvesting ; *** Central finger of the central hand.

Identical letters in the same column indicate that there is no significant difference at P<0.05.

S. de Oliveira e Silva, S. de Mello Véras, L. Gasparotto,

A. Pires de Matos, Z. Maciel Cordeiro,and B. Boher

The Moko disease of banana,caused by Ralstonia (Pseudomonas)solanacearum race 2 (Smith),

induces wilting of the leaves, startingfrom the young ones, and necrosis ofthe candle leaf as well. Immaturefruits of infected plants show yellowishcolor and dry rot of the pulp. Early in-fection, prior to flowering, causes ab-normal development of the bunch,fruit rot before ripening, and someplants may not yield a bunch. TheMoko disease can be disseminated ei-ther by insects, through infested soilor by root contact. These characteris-tics associated with unavailability ofresistant cultivars and low productiontechnology make the Moko disease avery serious problem for the bananacrop (Buddenhagen 1961, Stover 1972,Takatsu 1986, Matos et al. 1996).

R. solanacearum, race 2, was firstreported in Brazil in the Amazon Re-gion, State of Amapá (Tokeshi 1976).Currently this disease is also presentin the States of Amazonas, Para andAcre, all of them located in the Ama-zon Region (Takatsu 1986). Accordingto diagnostic surveys the number ofbanana orchards affected by the Astrain of R. solanacearum, race 2, inthe Amazon Region has been increas-ing in the past years (Matos et al.1996, Pereira et al. 1997).

Several recessive genes are involvedon the banana resistance to Moko(Vakilii 1965, Rowe and Richardson1975). Results reported by Stover(1972) showed several levels of sus-

ceptibility to Moko in banana cultivars,pointing out that the cultivar Pelipita(ABB) is highly resistant to thepathogen, thus indicating the geneticresistance as a viable control measurefor Moko in regions where the bananacrop is grown under very low produc-tion technology (Jones 1995).

Despite that possibility, no Moko-re-sistant germplasm was found whentetraploids (AAAB), such as PV03-44,JV03-15, PA03-22, Pioneira; triploids(AAA) Caipira, Nam, Nanica andNanic‹o, (AAB) Pacovan, Prata, PrataAn‹, Mysore, Thap Maeo and Ouro daMata; and plantains (AAB) Pacovi, Pa-covan and Bluggoe, (ABB) Figo, wereplanted in naturally infested soil (Silvaet al. 1998).

The objective of this paper was toevaluate the reaction of 31 diploid(AA) genotypes to the inoculation withR. solanacearum, race 2, aiming at se-lecting resistant ones to be used asmale parents in the banana breedingprogramme under conduction at theEmbrapa Cassava and Fruit Crops(CNPMF).

Material and methodsA total of 31 diploids (AA) genotypes -21 natural germplasm and 10 hybrids -from the Banana Germplasm Bank ofCNPMF, Cruz das Almas, State ofBahia, were evaluated. The experi-ment was carried out under green-house conditions, at the Embrapa Oc-cidental Amazon (CPAA), located inthe municipality of Manaus, Ama-zonas, North of Brazil, where the Mokodisease is endemic.

Eight plants of each diploid (AA)genotype were inoculated with theBiovar 1 of R. solanacearum, race 2,by injecting 1mL of a bacterial suspen-

sion, at a concentration of 108

CFU.mL-1, into the pseudostem, at 10cm from the soil level.

External symptoms were evaluatedat weekly intervals, based upon the fol-lowing disease rating scale:• No symptoms• Necrosis of the candle leaf• Yellowing of 2-3 leaves• Buckle of the petiole• Death of the plant

Plants without symptoms eightweeks after inoculation were consid-ered resistant to Moko disease.

Results and discussionSix weeks after inoculation the plantsstarted showing external symptomscharacteristics of the Moko disease.All plants that expressed externalsymptoms also showed vascular discol-oration characteristic of infection byR. solanaceraum, race 2. These re-sults indicate the efficiency of the in-oculation technique used to evaluateddiploid (AA) banana genotypes.

The natural germplasm Berlin,Buitenzorg, Fako Fako, Jambi, Jaran,Jari Buaya, Khai, Khi Maeo, Lidi, Mi-crocarpa, NBA 14, NBF 9, N⁄ 118, Ouro,P. Serum, Pipit, Pa Phathalung, Ton-gat, Tambi and Zebrina and the hy-brids 1304-04, 1318-01, 4223-06, F3P4,M-48 and M-61 showed susceptible reaction to the Biovar 1 ofR. solanacearum, race 2. On the otherhand, the diploid (AA) hybrids F2P2,1319-01, 1741-01 and SH3362, and BabiYadefana, a diploid cultivar from NewGuinea, expressed resistance to thepathogen. Some characteristics of thefive Moko-resistant genotypes are pre-sented in Table 1.

Although resistance to Moko diseasehas not been detected in triploid andtetraploid commercial varieties so far(Vakilii 1965, Silva et al. 1998), the re-sults presented in this paper show theoccurrence of genetic variabilityamong diploid (AA) banana genotypesable to express resistance to R. solanacearum, race 2.

The detection of resistance to Mokodisease in diploid (AA) genotypes

of a Seminar on The Fruits Industry in Malaysia,Jahor Bham, Malaysia.

Ho Y.W., C. Mak & Y.P. Tan. 1994. Strategies in theimprovement of banana cultivars for commercialscale cultivation. Pp. 71-82 in Proceedings of In-ternational Planters Conference, Kuala Lumpur,Malaysia.

Novak F.J., R. Afza, V. Phadvibulya, T., Hermelin, H.Brunner & B. Donini. 1986. Micropropagation

and radiation sensibility in shoot tip cultures ofbanana and plantain. Pp. 439 in Nuclear tech-niques and in vitro culture for plant improve-ment. IAEA, Vienna.

Novak F.J., R. Afza, M. Van Duren & M.S. Omar.1990. Mutation induction by gamma irradiationof in vitro cultured shoot tips of banana andplantain (Musa cvs.). Tropical Agriculture(Trinidad) 67: 21-28.

Orellana P.P., J. Pérez, D. Agramonte, R. Gómez, E.Jimenez, S. Martinez, E. Almaguer & R. Gómez.1991. La micropropagación del plátano a escalacomercial en Cuba. ACEVIC. Boletín Científico3(3): 29-38.


Genetic resources Diploid resistance to Moko

Evaluation of Musa spp. forresistance to Moko disease(Ralstonia solanacearum, race 2)

The authors work at the ‘Instituto de Biotecnologíade Las Plantas (IBP), UCLV, Santa Clara, Villa Clara,Cuba.

opens up a real possibility of creatingresistant commercial varieties,through conventional breeding tech-niques. Considering that only a smallnumber of genotypes was evaluated, itis expected that new sources of resis-tance to R. solanacearum, race 2would be detected as evaluations con-tinue. �

ReferencesBuddenhagen I.W. 1961. Bacterial wilt of bananas:

History and known distribution. Tropical Agricul-ture 38:107-121.

Jones D.R., ed. 1995. The improvement and testingof Musa: a global partnership. First Global Con-ference of the International Musa Testing Pro-gram, La Lima, Honduras, 27-30/04/1994. Inter-

national Network for the Improvement of Bananaand Plantain, Montpellier, France. 303p.

Matos A.P. de, S. de O. Silva & J.C.R Pereira. 1996.Doenças da bananeira no Médio Solimões, Ama-zonas: Moko, Mal-do-panamá e Sigatoka amarela.Informativo SBF, Brasília 15(4).

Pereira J.C.R., A.F. da S. Coelho, S. De M. Veras &L. Gasparotto. 1997. Levantamento da incidênciae prevalência de doenças vasculares da ba-naneira no Estado do Amazonas. Relatório Final.MA/Sedag, Manaus. 15p.

Rowe P.R. & D.L. Richardson. 1975. Breeding ba-nanas for disease resistance, fruit quality andyield. SIATSA. Bull. 2. Tropical Agriculture Re-search Service, La Lima, Honduras.

Silva S. De O., A.P. de Matos, J.C.R. Pereira, P.E.Meissner Filho, D.C. Costa & Z.J.M Cordeiro.1998. Actividades del Programa de Mejoramiento

de Banano en Embrapa Yuca y Frutales. InformeFinal del Proyecto IPGRI/AM-0694-96. Embrapa-CNPMF, Cruz das Almas. 25p.

Stover R.H. 1972. Banana, plantain and abaca dis-eases. Commonwealth Mycological Institute,Kew, Surrey, UK.

Takatsu A. 1986. Riscos e consequências da dissem-inação do Moko para outras regi›es do Brasil. Pp.54-59 in Simposio sobre Moko da bananeira,Manaus, AM 1984. Anais. Embrapa-CNPMF, Doc-umento 19. Embrapa-CNPMF, Cruz das Almas,BA.

Tokeshi H. & M.L.R. Duarte. 1976. Moko no Ter-ritório Federal do Amapá. Suma Phytopatholog-ica, São Paulo 2(3):224-229.

Vakilii N.G. 1965. Inheritance of resistance in Musaacuminata to bacterial wilt caused by thetomato race of Pseudomonas solanacearum.Phytopathology 55:1206-1209.


S. de Oliveira e Silva, A. Pires de Matos and Z.J. Maciel Cordeiro are Plant Breeder and PlantPathologists, respectively at Embrapa Mandicoa e Fru-ticultura, C. Postal 007, CEP 44380 000, Cruz dasAlmas, BA, Brazil. e-mail of first [email protected], S. de Mello Véras is lo-cated at Embrapa/CNPq, C. Postal 219, CEP69048.660, Manaus, AM, Brazil. L. Gasparotto isPlant Pathologist at Embrapa Amazonia Occidental,C. Postal 219, CEP 69048.660, Manaus, AM, Braziland B. Boher is Agronomist at INPA, C. Postal, 478,CEP 69011-970, Manaus, AM, Brazil.

Genetic resources National evaluation: Ghana

B.M. Dzomeku, B. Banful, A.A. Ankoma, D. Yeboah

and S.K. Darkey

Plantain and banana (Musa spp.)are very important starchy sta-ples in Ghana. They are con-

sumed both as energy-yielding food andas dessert. Plantain contributes about13.1 % of the Agricultural Gross Domes-tic product and its per capita annualconsumption of 85 kg per head ishigher than other staples such as maizeand yam. Plantain and banana are alsovery important sources of rural income(Ortiz and Vuylsteke 1996).

Despite their high value, productionhas been affected by growing pest anddisease pressures, the most notablebeing the fungal disease black Siga-toka (Mycosphaerella fijiensis). Thedisease was first observed at Assin-Fosu in the Central region of Ghana in

the early 1980s and has since spread toall the plantain-growing regions of thecountry. Yield losses due to the diseaseare highly significant, ranging from 20to 50%. Under very severe conditionsyield losses may be as high as 80%(Hemeng and Banful 1994).

The black Sigatoka disease can becontrolled with appropriate fungicidesbut the cost is prohibitive. Further-more, the fungicides are not environ-mentally-friendly and thus threatenthe fragile ecosystem. Consequently,the best viable alternative for the con-trol of black Sigatoka is through theuse of high-yielding resistant hybrids.

The Crops Research Institute intro-duced in 1994 some black Sigatoka-re-sistant/tolerant tetraploid hybrids ofMusa from Fundación Hondureña deInvestigación Agrícola (FHIA) in Hon-duras. The introduction was againstthe background that all the local lan-draces are susceptible to black Siga-

toka disease. The hybrids included onedessert banana (FHIA-01), one cook-ing banana (FHIA-03) and one Frenchplantain (FHIA-21).

Materials and methodsTissue culture plantlets of FHIA-21and FHIA-01 were received from theFundación Hondureña de Investi-gación Agrícola (FHIA) in Hondurasfor evaluation. The plantlets werehardened under a hardening shed forsix weeks before field planting.

The trials were established at threelocations, namely Fumesua in theAshanti region, Assin-Fosu in the Cen-tral region and Bunso in the easternregion. The locations were selected onthe basis of the variation in the soiltypes and the severity of black Siga-toka incidence. The design was a ran-domized complete block with threereplications. Three kilograms of poul-try manure were applied as soilamendment at planting. The plantingspacing was 3 m x 2 m (1667 plants/ha).

The disease evaluation was carriedout using the Stover scale of 1 to 10 asobserved on the third leaf.

Multilocational evaluation of FHIAhybrids in Ghana

Table 1. Some characteristics of diploids (AA) banana genotypes resistant to Mokodisease. Embrapa Occidental Amazon, Manaus, Amazonas, Brazil, 1998.

Genotype1 Height Fruits Length Reaction to diseases2

/bunch of fingers (cm)

Fusarium Yellow Black wilt Sigatoka Sigatoka

Babi Yadefana Low 60 12 _ S -

F2P2 Medium 96 12 - - -

1319-01 Medium 200 13 R R

1741-01 Medium 112 14 - R -

SH3362 High 192 15 - - S1 Babi Yadefana: cultivar from New Guinea; F2P2: hybrid from Ecuador; 1319-01: cross between Malaccensis x Tjau Lagada,selection 01; 1741-01: cross between Jary Buaya x hybrid (Calcutta x Madang); SH3362: hybrid from Honduras.2 R: resistant; S: susceptible.


Table 2. Yield and selected agronomic parameters of FHIA –01 at harvest between 1997-1999 at Fumesua, Bunso and Assin-Fosu.

Fumesua Bunso Assin Fosu

1997 1998 1999 Mean SE 1997 1998 1999 Mean SE 1997 1998 1999 Mean SE

Plant height at harvest (cm) 237.0 241.0 240.0 239.3 (1.0) 265.0 250.0 248.2 254.4 (18.9) 245.0 240.0 250.1 245.0 (5.7)

Height of tallest daughter sucker (cm) 180.0 170.0 168.0 172.7 (9.2) 180.0 172.3 167.4 173.2 (9.0) 120.0 128.0 118.0 122.2 (5.7)

Number of daughter suckers 3.2 5.0 6.3 4.8 (0.5) 5.2 6.1 4.0 5.1 (0.2) 3.0 6.0 4.0 4.3 (0.5)

Number of leaves at flowering 13.0 14.0 14.0 13.7 (0.1) 14.2 13.0 13.0 13.4 (0.1) 14.0 13.0 13.0 13.3 (0.1)

Number of leaves at harvest 7.0 8.0 7.0 7.3 (0.1) 5.6 7.0 8.0 6.9 (0.3) 6.0 8.0 7.0 7.0 (0.2)

Yield (t/ha) 38.3 40.8 41.1 40.1 (0.5) 42.7 39.4 38.5 40.2 (1.0) 30.7 34.2 55.6 33.1 (1.4)

Pseudostem (cm) 50.3 49.3 50.2 49.9 (0.1) 50.6 47.3 49.0 49.0 (0.6) 45.0 48.5 46.2 46.6 (0.7)

Number of months to flowering 11.3 11.4 11.3 11.3 (0.0) 11.3 11.3 11.4 11.3 (0.0) 11.9 11.4 11.6 11.6 (0.0)

Number of months to harvest 14.7 14.5 14.7 14.6 (0.0) 15.0 15.2 15.0 15.1 (0.0) 15.4 15.2 15.3 15.3 (0.0)

Number of hands/bunch 8.0 8.0 8.0 8.0 (0.0) 8.0 9.0 8.0 3.0 (0.1) 7.0 8.0 7.0 7.3 (0.2)

Number of fingers 109.0 103.0 112 108.0 (4.7) 110.0 102.0 104.0 105.3 (3.9) 101.0 98.0 99.0 99.3 (0.5)

Table 3. Yield and selected agronomic parameters of FHIA–03 at harvest between 1997-1999 at Fumesua, Bunso and Assin-Fosu.








Yield (t/ha) 38.3 36.8 36.1 37.1 (0.3) 34.3 34.0 34.5 34.2 (0.0) 25.3 26.4 27.8 26.5 (0.3)

Pseudostem (cm) 58.0 56.0 58.0 57.3 (0.3) 60.0 58.0 60.0 59.3 (0.3) 53.0 52.0 53.0 52.7 (0.1)




Number of fingers 92.0 90.0 94.0 92.0 (1.3) 91.0 90.0 93.0 91.3 (0.9) 93.0 90.0 92.0 91.7 (0.9)

Table 1. Yield and selected agronomic parameters of FHIA–21 at harvest (Fumesua, Bunso and Assin-Fosu)








Yield (t/ha) 41.7 38.4 39.2 39.8 (0.7) 30.3 32.4 35.7 33.7 (1.6) 35.3 37.4 38.5 37.1 (0.6)

Pseudostem (cm) 55.0 56.0 55.2 55.4 (0.1) 57.0 55.0 44.0 49.8 (10.9) 53.8 51.6 47.3 50.9 (2.4)




Number of fingers 108.0 98.0 115.0 107.0 (16.2) 99.0 100.0 101.0 100.0 (0.2) 98.0 99.0 97.0 98.0 (0.2)

Table 4. Comparison of yield and selected agronomic parameters of FHIA-21 with two French plantain landraces at Assin Fosuand Bunso.

1997 1998

FHIA-21 Apem Pa Apem oniaba SE FHIA-21 Apem pa Apem oniaba SE

Plant height at harvest (cm) 252.3 352.0 273.0 30.4 256.0 353.0 272.0 30.0

Pseudostem girth (cm) 54.7 59.2 47.1 3.3 49.7 57.5 50.3 2.5

Number of daughter suckers 5.3 4.5 7.0 0.7 4.7 4.0 6.0 0.6

Number of leaves at flowering 12.1 10.0 8.0 1.2 13.3 11.0 9.0 1.2

Number of leaves at harvest 7.3 4.0 1.0 1.8 7.0 4.0 2.0 1.5

Number of months to harvest 14.8 18.0 16.2 0.9 15.0 18.5 17.0 1.0

Number of hands/bunch 7.3 8.0 6.0 0.5 8.0 8.0 6.0 0.6

Number of fingers/bunch 101.0 109.0 98.0 0.5 100.0 111.0 100.0 0.7

Yield (t/ha) 35.7 24.0 15.8 5.7 36.5 25.3 16.3 5.8

Bakelana-ba-Kufimfutu, Vangu Phakaand Mputu Kena Kudia

Bananas are a staple food for theCongolese and also a very impor-tant source of income for the

farmers who grow them.An exploratory survey was per-

formed among banana growers to in-crease the body of production statis-tics. It was conducted in the variousproduction zones in the Congo.

The survey was started in theCataractes District in the Mbanza-Ngungu area and the Bas-Fleuve(Lower Congo) District in the Sehe-banza area. Thirty-six farmers werequestioned about various aspects ofthe cultivation and marketing of ba-nanas. The results of the first part ofthis survey are provided below.

MethodologyAn inventory of banana productionzones was performed in the LowerCongo region. On the basis of the fi-nancial and material resources avail-able, several farmers selected at ran-dom were interviewed by thepersonnel of the INERA M’vuazi Ba-nana Programme. The number of farm-

ers questioned was proportional to thesize of the village.

ResultsThe use of farmers’ banana productionBananas are both a foodstuff and asource of income for most of the farm-ers questioned. Growers hardly everuse banana in the production of localbeverages; these are generally basedon pineapple, sugar cane and orange(Table 1). They do not usually knowthe precise quantity of bananas pro-duced, eaten or sold on the marketeach year.

Area and ownership of cultivated landAlthough the area cultivated by eachfarmer is not known precisely, thefarmers in the Lower Congo districtfarm larger holdings than those in theCataractes district (Table 2). This isexplained by the on-farm consumptionof bananas in each district (Table 1)and also by the more or less favourablenature of the production environment(savannah in the Cataractes districtand forest in the Lower Congo). Asfarmers cultivate with hoes, the areasdo not exceed 1 hectare.

Land belongs mainly to the extendedfamily. Some husbands living in their

in-laws’ villages cultivate the latter’sland. Nevertheless, 27% of the farmersrent their land in the Sehebanza areain the Lower Congo district wherethere are large banana plantations inthe forest area (Table 3).

Types of bananas grownAll the farmers questioned grow bothsweet bananas and plantains. Cookingand beer bananas are not grown in thedistricts surveyed. In certain circum-stances, some families use sweet ba-nanas as cooking bananas and ex-tremely ripe plantains for themanufacture of local beverages.

Cropping systemsBanana monoculture is more impor-tant in the Lower Congo district thanin the Cataractes district (Table 4).Home gardens are also more frequentin the Lower Congo district because ofthe importance of banana as a staplefood for the population of this district.

Sucker planting systemMost farmers replant suckers directlyin the field after desuckering (81% inthe Cataractes district and 93% in theLower Congo district). Only 19%(Cataractes) and 7% (Lower Congo) of

Results and discussionAt each of the three locations,FHIA–21 exhibited stable performancein yield and growth characteristicsover the three years of study (Table 1).The performance of FHIA-21 in yieldand growth characteristics over theyears in all three locations was consis-tent and suggested its stability. Similartrends were observed in FHIA-01(Table 2). These results suggested thatperformance of FHIA–21 and FHIA-01was not influenced by seasons or loca-tions. It implies that under good man-agement practices, farmers would beassured of good yields irrespective oftime or season of planting so long asthere is adequate supply of moisture.

FHIA-03 (cooking banana) showedconsistency in yield and growth perfor-mance over the years (Table 3). The

agronomic characteristics of the hy-brid were not affected by location. Thehybrid was however not well acceptedby consumers.

Comparing the performance ofFHIA-21 with the land races Apem paand Apem oniaba, FHIA-21 exhibitedsuperiority in growth and yield for allthe locations tested (Table 4). FHIA-21was 21% shorter in height and 8%thicker in pseudostem girth than themean of the landraces, which sug-gested that plants of FHIA-21 weresturdier than the landraces. It istherefore more likely that FHIA-21would escape stem lodging. Earlierwork (Hemeng et al. 1994) indicatedthat plants with thicker pseudostemgirth experienced less stem lodging.FHIA-21 also retained more functionalleaves at flowering than the landraces,

which possibly contributed to itshigher yield (Table 4): FHIA–21 pro-duced 43% more than the landraces. �

ReferencesHemeng O.B. & B. Banful. 1994. Plantain Develop-

ment Project. Government of Ghana and Interna-tional Development Research Centre, Canada.Final Technical Report 1991-1993.

Ortiz R. & D. Vuylsteke. 1996. Improving plantainand banana-based system. Pp. 23-27 in Plantainand Banana Production and Research in Westand Central Africa. Proceedings of a RegionalWorkshop, September, 1995 (R. Ortiz & M.O.Akoroda, eds.).


The authors work at the Crops Research Institute,PO Box 3785, Kumasi, Ghana.

Socioeconomics Survey of banana producers

Results of a survey on bananas conducted amongfarmers in the Democratic Republic of Congo


farmers plant them in holes preparedin advance in the field.

Fertilisation of bananasBananas must be fertilised with inor-ganic or organic fertiliser to ensurethe satisfactory nutrition of the grow-ing plants.

Most farmers do not fertilise banana.Those who do so use organic wastes(10% in the Cataractes district). Theuse of inorganic fertiliser is non-exis-tent among smallholders.

Origin of the planting materialBanana was an industrial crop in theLower Congo district 30 years ago and

enormous quantities of ‘Gros Michel’fruits were produced and exported toBelgium. The degeneration of the cul-tivars and the continual destruction ofthe old plantations made it difficult forfarmers to obtain planting material.

A large proportion of planting mater-ial is produced naturally by the farm-ers themselves. Some obtain betterquality material from their neighboursthrough good relations. Purchases ofplant material on the market are rare(Table 5).

The storage of banana productsFarmers store their produce in differ-ent ways. Most keep their harvest inthe village in sheds and in small build-ings next to their houses for better su-pervision and to prevent theft (Table 6).

DiseasesBanana-growing is often affected byvarious fungal, bacterial and viral dis-eases and by pest damage. Only theborer called «Nyombé» is identified bymost of the farmers questioned. In ageneral manner, as a result of lack oftraining, the farmers do not recognisethe different diseases. For example,they think that black Sigatoka diseaseof banana is leaf wilt because theplant is old.

Organisation of work in the fieldWho do male or female farmers workwith in the field? In more than 40% ofcases, the nuclear family (husband,wife and children) participate in field-work. Nevertheless, a large number ofhusbands work alone in the fieldswhile their wives perform other familyactivities (Table 7).

The uses of bananaBananas have many uses that varyfrom one zone to another. All the farm-ers questioned use sweet bananas as a dessert. Some also eat plantain; it is boiled or prepared as a paste for use as a condiment with other foods (Table 8).

Distribution of productionBananas are above all a source of in-come for the farmers questioned. On-farm consumption represents ap-proximately 30% of total production(Table 9).

Marketing of bananasVery few farmers sell banana bunchesin the field. The great majority selltheir harvest in the village to middle-men who come from urban centres.Village banana sales are substantialwhere access to the villages is good, asin the Lower Congo area (Table 10).

Few traders go to the villages in the Cataractes district, where theroads serving farms are often in poorcondition. Many farmers go to localmarkets in person to sell their produce (Table 10). �

Table 1. Use of the bananas grown byfarmers.

Use Distribution of farmers by district (%)

Cataractes Lower Congo

Consumption 40 70

Manufacture of local beverage 0 0

Source of income 90 100

Table 2. Cultivated area.

Area (ha) Distribution of farmers by district (%)


≤0.10 57 7

≤0.50 24 63

≤1.00 19 30

Table 3. Ownership of cultivated land.

Owner of the Distribution of farmersland cultivated by district (%)


Extended family 86 60

In-laws 14 10

Other 0 27

Table 4. Cropping systems.

Cropping systems Distribution of farmers by district (%)


Monoculture in savannah 17 10

Monoculture in forest 16 35

Intercropping 50 10

Home gardens 17 20

Table 5. Sources of supply of plantingmaterial.

Sources of supply Distribution of farmers by district (%)


Farmer’s field 57 67

From a neighbour 17 33

Purchased on the market 26 0

Table 6. Storage locations.

Storage location Distribution of farmers by district (%)


In the farmer’s field 20 0

In the village 80 100

At the market 0 0

Table 7. Smallholding labour.

Labour Distribution of farmers by district (%)


Husband alone 43 27

Husband and wife 10 27

Nuclear family 43 47

Extended family 4 9

Table 8. The uses of banana.

Uses of banana Distribution of farmers by district (%)


Eaten as dessert 100 100

Boiled 86 40

Pounded to paste 14 60

Local beer 0 0

Table 9. Distribution of production.

Distribution Distribution of farmers of production by district (%)


On-farm consumption 29 35

Source of income 71 65

Table 10. Marketing of bananas.

Sale Distribution of farmersby district (%)


In the field 0 0

In the village 42 76

At the roadside 4 10

On local markets 30 6

In urban centres 22 0

The authors work at the Institut National pourl’Etude et la Recherche Agronomique, BP 2007, Kin-shasa I, Democratic Republic of Congo.


Agroeconomics Market potential for cooking bananas

J. Cabrera Cabrera and V. Galán Saúco

The cultivation of cooking bananasin the Canary Islands is limitedto a few isolated plants at field

edges or gardens. There is no commer-cial cropping or organised marketing.

The cultivar ‘Topocho Verde’ (ABB)was tested to perform a preliminaryagronomic and commercial explo-ration. The fruit of the variety is wellknown and much appreciated by LatinAmerican emigrants who come mainlyfrom Cuba and Venezuela and formsubstantial population groups not onlyin the Canary Islands but also in Spainand in Europe as a whole.

In addition, interest in the diversityof food available in the tourist sec-tor—a pillar of the Canary Islandeconomy—could contribute to promot-ing the establishment of this cultivaror others of the same type.

Design and performance of the experimentThe experiment was performed in twoplots in different zones, one in theopen air at Guía de Isora in southernTenerife and the other in glasshouses 9m high at Gáldar in the north of GranCanaria island.

The plant material used was fromthe ICIA germplasm collection andwas multiplied in vitro by ICIA’s Orna-mental Plants and Horticulture De-partment, thus ensuring good sanitary

condition. It is thought that the cloneis similar to the cultivar ‘Bluggoe’ or‘Cachaco’.

The main data concerning the start-up of the experiment are shown in theTable below.

Plot Planting Plantation Density date characteristics (plants/ ha)

Open 26/08/1996 2.5 m x 5.0 m 2400air (3 plants

per hole)

Green 17/01/1997 2.0 m x 6.0 mhouse (2 plants 1666

per hole)

Local fertigation and a cultural pro-gramme in conformity with those gen-erally used for the cultivar ‘Grandenaine’ were applied. The pseudostemwas cut back to a height of 1.50 m inthe greenhouse in the second cycle toprevent the plants from growing exces-sively tall.

The most significant data wererecorded for the appraisal of bothagronomic practices and the produc-tivity of the two types of plantation.The fate of the fruits harvested wasalso monitored as far as retail sale toconsumers in order to study the com-mercial potential and the degree of ac-ceptance on the local market.

Results and conclusionsThe data in Table 1 show the results inthe two plots studied and lead to esti-mating a potential yield of approxi-mately 40 tonnes per hectare.

In the greenhouse, the pruning ofthe plants in the second productioncycle to prevent them from growingtoo tall resulted in a considerable de-crease in harvest quantity. It wouldtherefore be necessary to seeksmaller clones, which would alsomake handling easier and increasethe wind resistance of open fieldplantations.

For this reason and with a view to afuture evaluation, a dwarf clone intro-duced from Venezuela and cultivatedin the Canary Islands by a local pro-ducer is being multiplied in vitro. Inparallel, other mutants whose possiblesmall height might be interesting arecurrently being selected.

In addition, fruits with a more orless intense silvery colour have beennoted, although it is not yet possible toconfirm that this character will bemaintained in subsequent cycles. If this were to be the case, differenti-ated lines should be bred and the in vitro cycle started again to multiplythem and verify the stability of this parameter.

The degree of acceptance on thelocal market is very high as the pricepaid was over double that of dessertbananas. In addition, the fact that thefruits are sold green with no ripening,unlike dessert bananas, is a definiteadvantage for the farmer and retailerand should be mentioned here.

Being able to propose a cooking ba-nana that fills a market slot—however

Preliminary study on the advantages of the cooking banana‘Topocho verde’ (ABB) for the Canary Islands

An international workshop oncooking banana in subtropicalzones was held from 29 Novem-

ber to 3 December 1999 at InstitutoCanario de Investigaciones Agrarias(ICIA, Tenerife, Spain). It was at-tended by Ramón Valmayor from thePhilippines, Sylvio Belalcázar fromColombia, Thierry Lescot from France(CIRAD-FHLOR) and, for ICIA, JuanCabrera Cabrera, María José GrajalMartín and Victor Galán Saúco, the co-ordinator of the meeting. The event

was held in the light of the need tostudy the potential of cooking bananasin the subtropics.

The present importance of cookingbanana in various parts of the world(Asia, America and Africa) was de-scribed. Discussions covered the mostimportant groups or cultivars in thelight of the agronomic characteristicsand potential that these types of ba-nana might represent in subtropicalzones. It was suggested that it mightbe advantageous to open an interna-

tional “work space” co-ordinated byINIBAP to evaluate plant materialother than Cavendish for subtropicalzones.

The conclusion consisted of the firstcensus of the various cooking bananasand of several banana types other thanCavendish that could be evaluated insubtropical zones. Special attentionwas paid to the “low habit” parameterof the plants. The list includes the pos-sible origins of cultivars with maxi-mum guarantees that might be en-trusted to INIBAP for subsequentstudy. This could include characterisa-tion and evaluation in subtropicalzones. Three of the papers delivered atthe meeting are published below.

Round table on cooking banana insubtropical zones


T. Lescot

Banana production in Africa wasestimated to total some 29.6 mil-lion tonnes in 1998, represent-

ing 33.8% of world production.African production is distributed as

follows (Figure 1):• Plantains (AAB group, “Plantain”

subgroup): 10.3 million tonnes (ofwhich about 6000 tonnes is exportedannually), forming 34.9% of totalAfrican production.

• Other cooking bananas (AAA, ABBand AAB groups, excluding the“Plantain” subgroup): 12.56 milliontonnes, forming 42.5% of totalAfrican production.

• Dessert bananas (AA, AAA and AABgroups): 6.7 million tonnes (includ-ing 467 000 tonnes exported eachyear), i.e. 22.6% of total African pro-duction.Total in 1998: 29.6 MT = 33.8% of

world productionTable 1 provides data on production

by types, export estimates for 1998/99as well as data on per capita consump-tion and planted areas.

Distribution of varieties,utilisationAlthough it is true that bananas origi-nated in South-East Asia, Africa has

contributed to the diversity of thegenus Musa by enriching it with twosecondary lines of diversification:• “Plantains” (AAB), in central Africa,

with about 100 cultivated varietiesor clones.

• East African highland bananas(AAAea), with about 100 cultivatedvarieties or clones.

Practically all the groups and sub-groups of the genus Musa (“Eumusa”section) are represented in Africa andare almost all eaten in two forms: freshand/or cooked (or processed):AA: SucrierAAA: Gros Michel, Red, Ibota, Luju-

gira/Mutika (AAAea)AAB: Plantain, Silk, Pome (Prata)

Figure 1. Musa production in Africa.

" Cavendish "Bananas17,2 %

Other" dessert "

Plantain

Export

LocalConsumption

Total in 1998 : 29,6 MT = 33,8 % of world production

5,4 %1,6 MT0,5 MT

34,9 %

Export (6000 t)

Other cookingbananas

15,6 %

42,5 %

tiny—that will doubtless grow shouldbe taken into account by Canary Islandgrowers. The experiment was thus in-tended to open up a pathway by show-

ing that there is real scope for theprofitable cultivation of a banana cul-tivar that differs from traditional varieties. �

The authors work at the Departamento de Fruticul-tura Tropical, Instituto Canario de InvestigacionesAgrarias (ICIA), Apdo 60, La Laguna, Tenerife, CanaryIslands.

The importance of plantains and cooking bananas in Africa:outlets for the subtropical zones

Table 1. Topocho Verde (ABB) cooking banana – Results of trials.Pseudostem Pseudostem (A)/(B) Hands Harvest Bunch Estimated yield

height (cm) (A) diameter (cm) (B) per bunch date weight (kg/ha)(kg)

Open air 1st cycle 358 60.0 5.95 6.8 07/01/98 18.5 35 899

Open air 2nd cycle 399 65.0 6.17 6.3 03/12/98 21.8 42 294

Greenhouse 1st cycle 517 71.9 7.19 8.0 16/05/98 33.4 45 047

Greenhouse 2nd cycle 499 70.9 7.04 6.3 27/03/99 20.9 28 136

Upper 2nd hand Lower 2nd hand

Finger Finger No. of fingers Finger length Finger width No. of fingerslength (cm) width(mm) (cm) (mm)

Open air 1st cycle 20.0 43.0 13 19.0 41.0 12

Open air 2nd cycle 22.0 48.0 12 19.0 45.0 12

Greenhouse 1st cycle 28.2 50.3 nd 24.5 47.5 nd

Greenhouse 2nd cycle 28.4 46.8 nd 25.3 44.0 ndnd: no data.


ABB: Bluggoe, Pisang awak, Monthan,PelipitaThe multiplicity of ethnic groups re-

sults in great variety in practices inproduction, consumption, processingand the use of by-products.

Considerable variety is observed inculinary preparations:• Boiled (green) whole• Boiled (green) for purée (crushed

fruit)• Fried in oil (ripe/semi-ripe)• Grilled over embers/in the oven,

with or without peel (ripe/semi-ripe)

• Ground/crushed (green) and thendried and mixed with flour andwater to form a paste/purée

• AAAea: the (ripe) fruits are set toferment; the juice is extracted andfermented to make “beer/wine” ordistilled to make alcohol

• AAB plantain and ABB cooking ba-nanas: chips and a variety of otherproducts.There are also many by-products:

• Ash prepared from burned bananapeel (high potassium content) isused in soap-making

• Dried, half-burned peel is an addi-tive for tobacco

• Dried sucker fibres (stem) are usedto manufacture sponges

• Fresh pseudostem is used as cattlefeed

• Pseudostems, petioles and the cen-tral vein of dried leaves are used forthe manufactures of rope, es-padrilles, etc.

• Dried/fresh leaves are used in mate-rials for packing, roofing, etc.Bananas form an important part of

the diet and are much appreciated as

Table 1. Bananas and plantains in Africa: production, export, consumption and planted areas (source: T. Lescot 1999, FruiTrop 63).Production of bananas and plantains (tonnes) Estimate 98/99

Plantains Highland bananas Cavendish Gros Michel + TOTAL Export Consumption AreaAAB ABB + other bananas other dessert (kg/capita) (ha)

cooking bananas bananas Plantain Commercial

Cavendish Plantains Bananas Plantains bananas

Afrique occidentale et centrale

Angola 140000 10000 275000 10000 435000 23,47 11,95 23333

Benin 3000 100 13000 14950 31050 2,31 0,53 207

Cameroon 1030000 30000 456000 500000 2016000 220000 5000 16,95 73,61 200000 5700

Cape Verde 1 1 8000 1 8003 1000 17,54 0,00 160

Congo 66000 10000 31000 6000 113000 11,44 24,36 11000

Côte d’Ivoire 1200000 10000 390000 10000 1610000 199700 128 13,53 85,32 200000 5620

Gabon 120000 30000 11000 10000 171000 9,67 105,54 20000

Ghana 1798000 60000 19000 500 1877500 3400 500 0,84 96,35 299667

Guinea 419000 10000 130000 10000 569000 17,75 57,20 69833

Guinea Bissau 34500 1000 4000 500 40000 3,52 30,37 5750

Equatorial Guinea 8000 1000 7000 1000 17000 16,67 19,05 1333

Mali 10 10200 10 10220 0,98 0,00

Liberia 35000 5000 58000 22000 120000 24,15 14,57 5833

Nigeria 1675000 12000 10000 20000 1717000 1 0,10 16,12 279167

Sao Tome & Principe 6500 1500 4200 3800 16000 2 30,43 47,09 1083

Senegal 100 10 7500 900 8510 0,85 0,01 17 800

Sierra Leone 26000 500 1000 500 28000 0,23 5,88 4333

Togo 1000 500 14100 500 16100 15 72 3,29 0,22 167

Central African Rep. 70000 10000 60000 40000 180000 17,54 20,47 11667

Zaire (CDR) 2250000 462400 339600 80000 3132000 1 7,08 46,89 380000

TOTAL 8882101 654021 1848600 730661 12115383 424115 5704 5.42 33.77 1513390 12280

% 73.31 5.40 15.26 6.03 % 3.50 0.05

Eastern Africa

South Africa 199500 500 200000 464 5,14 0,00

Burundi 70000 1100000 80000 274500 1524500 74 12,57 10,99 11667

Comoros 10000 10000 27000 10000 57000 42,19 15,63 1667

Ethiopia 81000 81000 1,39 0,00

Kenya 390000 135000 120000 10000 655000 66 3 4,22 13,71 65000

Madagascar 1000 5000 229000 30000 265000 5900 15,26 0,07 167

Malawi 202000 5000 84000 2000 293000 8,34 20,07 33667

Maurice 1 5 9000 10 9016 7,94 0,00

Mozambique 1000 1000 84000 1000 87000 4,55 0,05 167

Uganda 310000 9000000 425000 100000 9835000 2557 200 21,12 15,49 51667

Reunion Island 1 5 10000 10 10016 14,86 0,00

Rwanda 100000 1568000 145000 435000 2248000 7 24,32 16,77 16667

Seychelles 100 500 1100 250 1950 14,67 1,33 17

Somalia 2000 10 51000 20 53030 25000 2,95 0,23 333 1000

Sudan 70500 70500 2,54 0,00

Swaziland 500 500 0,54 0,00

Tanzania 350000 80000 345000 2912 777912 10,98 11,14 58333

Zambia 600 600 0,07 0,00

Zimbabwe 80000 80000 2012 6,95 0,00

TOTAL 1436102 11904520 2042200 866202 16249024 35999 284 6.87 4.92 239350 1000

% 8.84 73.26 12.57 5.33 % 0.22 0.00


a source of energy (carbohydrate).With an average of 10 tonnes per haper year, production totals approxi-mately 12 million kilocalories per haper year. Assuming an average produc-tion cost of $US 1000 per ha, one dollarproduces 6000 kilocalories.

Farming systemsCropping and farming systems are veryvaried and display various aspects:• Production strategies vary consider-

ably: means of subsistence, on-farmconsumption, clearing of tropicalforest, intercropping with other cashcrops (coffee, cocoa, etc.) and/or

other food crops, intensive cropping(market), production for export etc.at various densities.

• Bananas are a cheap, steady food-stuff. Production costs are very lowand bunches can be harvestedweekly.

• Bananas are also a steady source ofincome, with cultivation all the yearround and bunches produced everyweek.

• Banana is a sustainable crop, withfairly well-balanced carbon cycleand nitrogen.

• Yields are variable but usually low at4 to 30 tonnes per ha.

Capacity for adaptation intropical zones• Small fresh bananas (AA, AAA,

AAB): adaptation capacity is gener-ally small to medium, with the ex-ception of ‘Silk’ AAB (grown in Aus-tralia and South Africa) and certainAsian diploids (AA) whose adapta-tion remains to be demonstrated.

• “Plantains” (AAB): adaptation ca-pacity only in the ‘French’ subgroupclones from highland areas, with theexception of certain members of the‘False horn’ group.

• Highland bananas (AAAea): infor-mation is lacking but adaptation ca-pacity should exist.

• Other ‘cooking’ bananas (ABB):adaptation capacity small tomedium.

Susceptibility to pests anddiseasesLevels of susceptibility of the variousbanana types to yellow and black Siga-tokas, Fusarium wilt and nematodesare presented in Table 2.

Marketing potentialEven if the export of non Cavendishbananas is presently limited to touristor ethnic “niche” markets, there is nodoubt that the European market half-opens to these other bananas (Table 3,Loeillet 1999).

ConclusionFairly great diversity of Musa is ob-served in Africa (the second centre of

Table 1. continuedProduction of bananas and plantains (tonnes) Estimate 98/99

Plantains Highland bananas Cavendish Gros Michel + TOTAL Export Consumption AreaAAB ABB + other bananas other dessert (kg/capita) (ha)

cooking bananas bananas Plantain Commercial

Cavendish Plantains Bananas Plantains bananasNorth Africa/Middle East

Bahrain 800 800 1,37 0,00

Cisjordan 7900 7900 24,69 0,00

Egypt 10 1000 635115 636125 11 1 9,81 0,00 14000

United Arab Emirates 150 150 0,07 0,00

Gaza strip 7000 7000 5000 2,01 0,00

Iran 8000 8000 0,12 0,00

Israel 111900 111900 777 18,96 0,00

Jordan 72504 72504 14 16,03 0,00 1700

Lebanon 10 110000 110010 1 35,00 0,00

Morocco 102000 102000 3,79 0,00 2960

Oman 28000 28000 647 11,87 0,00 1114

Syria 160 160 0,01 0,00

Tunisia 55 55 1 0,01 0,00

Turkey 37000 37000 360 0,58 0,00

Yémen 85110 85110 5,22 0,00

TOTAL 20 1000 1205694 0 1206714 6810 2 4,28 0,00 0 19774

% 0.00 0.08 99.92 0.00 % 0.56 0.00

TOTAL 10318223 12559541 5096494 1596863 29571121 466924 5990 8,34 18,58 1752740 33054AFRICA

% 34.89 42.47 17.23 5.40 % 1.58 0.02

Table 2. Susceptibility of bananas to pests and diseases.

Group/clone YS BS Foc Borer Nematodes

AA

Sucrier *** * * ***

AAA

Gros Michel (1) *** *** *** * **

Red ** *** * **

Ibota (Yangambi Km5)

Lujugira/Mutika (AAAea) *** *** ** *** ***

AAB

Plátano * ** *** ***

Silk *** *** *** ** ***

Pome (Prata) *** *** ** ***

ABB

Bluggoe (2) * *** * **

Pisang awak * * *

Monthan * * *

Pelipita * * *YS: Yellow Sigatoka; BS: Black Sigatoka; Foc: Fusarium oxysporum f. sp. cubense; *: resistant; **: partially resistant; ***: susceptible; (1) A Cuban clone of ‘Gros Michel’ is resistant to Foc (1-2);

(2) A Cuban ‘Bluggoe’ type clone is resistant to Foc (2): “Burro CEMSA 3/4”.


R. V. Valmayor

Bananas are considered to be oneof the earliest fruits cultivatedby man. The oldest reference to

banana appears in the Ramayana, aSanskrit epic written centuries ago.The magnificent Buddhist temple,Borobudur, constructed in centralJava, Indonesia, in 850 BC show stonecarvings of banana being offered to theLord Buddha. The victorious armies ofAlexander the Great described the cul-tivation of banana in the lower HindusValley of India in 327 BC. South Chinais another area where banana cultiva-tion dates back to ancient times.Scriptures written during the reign ofHan dynasty (206 BC - 220 AD) men-tioned the cultivation of banana morethan 2,000 years ago. Because of its an-tiquity, its long history of domestica-tion in India and China and the greatdiversity of dessert and culinary culti-vars present in these two countries,some writers believed that bananasoriginated in India or China. However,results of banana exploration missionsin Asia during the middle part of thiscentury and the subsequent unveilingof the great wealth of Musagermplasm resources collected showedthat it is more likely that bananas ac-tually originated in Southeast Asia.

Banana classification in Southeast AsiaBanana classification and nomencla-ture have been a complicated issuefrom the very beginning. The problemstarted with the simplistic descriptionof plantain, Musa paradisiaca Linn.and dessert banana, Musa sapientumLinn. by Karl Linnaeus, the father ofmodern botanical nomenclature. Thecomplication emanated from the verylimited specimens available to Lin-naeus in Europe where the originalnames were given. While the differen-tiation between plantains, a specialtype of cooking banana and dessert ba-nanas is readily applicable in Africaand Latin America, their adoption inSoutheast Asia has led to confusion.This is because in the center of Musadiversity, many local cultivars possesscharacteristics that transcend the di-agnostic characters used elsewhere todifferentiate bananas and plantains

In the center of diversity for ba-nanas, many cultivars are classified asdual purpose, the fruits are consumedeither fresh or cooked. There are alsomany starchy, cooking cultivars withshort, stout and angular fruits with de-hiscent male flowers and bracts. Thesecooking bananas are distinct from theplantains and cannot be classifiedunder Musa paradisiaca. Further-more, the great diversity of dessert ba-nanas in terms of plant stature, fruit

size and colour (yellow, green, red, andorange) far exceed the rather limiteddescription of the original Musa sapientum. To cope with the wealth ingermplasm diversity in its center oforigin, subsequent banana taxonomistsapplied such descriptive names asMusa nana Lour. for the DwarfCavendish, Musa rubra Firming. von Wall.for the Red banana, Musa corniculataLour. for the Horn plantain, and manyothers. The proliferation of scientificnames added more confusion to ba-nana nomenclature and the situationwould have worsened if it were not forCheesman (1948) and Simmonds andShepherd (1955) who explained theorigin of edible bananas and proposeda new classification scheme.

Drawing upon their expertise in ge-netics and vast experience in cytotax-onomy, Simmonds and Shepherd con-cluded that the Linnean scientificnames Musa paradisiaca and Musasapientum were based on hybrid culti-vars and recommended their abolition.They likewise concluded that the edi-ble bananas originated from two wildand seedy species, Musa acuminataColla and Musa balbisiana Collawhich are endemic to Southeast Asia.Cheesman recognized three groups ofmorphologically distinct cultivars. The firstgroup shows predominantly the botanicalcharacters of Musa acuminata while thesecond group of cultivars primarily ex-

diversity after South-East Asia, thezone of origin), especially in the fol-lowing subgroups: plantain (AAB) and

East African bananas (AAA). Variousclones can develop normally undersubtropical climatic conditions, with a

preliminary first stage of behaviourtests, with regard to both agronomyand the post-harvest/ripening period.In the Canaries, development of theproduction of these varieties dependson the realities of the potential mar-ket, which cannot be very great. In-deed, these are ‘niche’ markets re-sponding to tourist or ethnic demand(local consumption, Spain and Eu-rope). �

ReferencesLescot T. 1999. Banana: production, trade and vari-

eties. FruiTrop 63: 13-16.Loeillet D. 1999. Le marché international bananier:

une gamme de produits très étroite. Pp. 567-576in Bananas and Food Security/Les productionsbananières: un enjeu économique majeur pour lasécurité alimentaire (C. Picq, E. Fouré & E. Fri-son, eds). Proceedings of an international sympo-sium held in Douala, Cameroon, 10-14 November1998. INIBAP, Montpellier, France.

The author works at CIRAD-FLHOR, BP 5035, 34000Montpellier cedex 1, France.

Table 3. Market potential of non Cavendish bananas in European Union.

Group/clone European imports Trend Origin Price***(tonnes) ee/kg

AA

Sucrier* 18 000 ➚ Latin Am./Africa 2.3-5.7

AAA

Gros Michel*, ** 30 000 ➚ Latin Am./Africa ?

Red 4 000 ➚ Latin Am./Africa 1.2-3.7

Ibota (Yangambi Km5) -

Lujugira/Mutika (AAAea) -

AAB

Plátano* 24 000 ➚ Latin Am./Africa 0.55-1.4

Silk* 2 000 Latin America 2-5

Pome (Prata) -

ABB

Bluggoe -

Pisang awak -

Monthan -

Pelipita -* with ‘organic’ potential

** processed: purée

*** wholesale price.

Cooking bananas – Classification, production and utilization in South-East Asia

➚

hibits the morphological features ofMusa balbisiana. The third group pos-sesses characteristics that blend themorphological characters of the twowild species and are considered astheir natural hybrids. The primitiveedible bananas were diploids thatevolved through the development ofsterility and parthenocarpy in Musaacuminata. Through human selection,various clones were brought under cul-tivation particularly in the rainy partsof Southeast Asia. Later, through chro-mosome restitution, seedless triploidcultivars developed. Since triploidsproved to be more vigorous and pro-ductive, they gained greater popular-ity. Cheesman argued that the seed-less, edible diploid cultivars of Musaacuminata must be treated in thesame species as their wild parents asthey retained the morphological char-acteristics of their wild ancestors.Likewise, the seedless and edibletriploid cultivars that developedthrough chromosome restitution mustalso be recognized as the same speciesas their parents because the additionof one set of chromosomes through au-topolyploidy did not introduce any-thing new to the genetic constitutionof the clone. In the drier areas ofSoutheast Asia where the wild andseedy Musa balbisiana predominate, aparallel evolutionary development oc-curred which led to the appearance ofpure diploid and triploid balbisianacultivars (Valmayor et al. 1991). Sincethe development of sterility andparthenocarpy did not significantlyalter the morphological characteristicsof the resultant clones, the scientificname Musa balbisiana should also beapplied to the edible diploid andtriploid cultivars derived from the wildbalbisiana parents. In the center oforigin of bananas, the natural distribu-tion of wild Musa acuminata andMusa balbisiana overlap and sincethe two species are cross compatible,hybridization occurred. The hybridsthat evolved from the two naturalspecies include diploids, triploids anda few tetraploids in various genomecombinations. A major concern aboutthe original terms Musa paradisiacaand Musa sapientum is their hybridnature. But according to ICNCP rules(International Code of Nomenclaturefor Cultivated Plants) hybrids can alsobe given a scientific name. However,the epithet must carry the prefix x toindicate the hybrid nature of thespecies. In the case of hybrid bananacultivars, Musa x paradisiaca Linn.should be adopted as this binomialwas published ahead of Musa sapien-tum and is in fact recognized as the

type species for the banana. Musa xparadisiaca Linn. is applicable to allhybrids of Musa acuminata and Musabalbisiana notwithstanding theirgenome composition (Greuter 1994,Karamura 1998).

The genome composition of bananacultivars helps in differentiatingdessert from cooking varieties. Allpure Musa balbisiana clones are cook-ing bananas while many of the pureMusa acuminata varieties are dessertbananas. Among the hybrids are dualpurpose cultivars (consumed eitherfresh or cooked), dessert and cookingbananas, including the plantains. Thegeneral term plantain is applicableonly to a specific subgroup of cookingbananas and do not include the nu-merous and divergent cooking culti-vars that are very popular in Asia. Onthe other hand, the term banana is notlimited to the dessert varieties butalso cover all the cooking bananas, in-cluding the plantains. In other words,all plantains are also bananas but notall bananas are plantains! This is thereason why in Southeast Asian lan-guages, there is no differentiation be-tween the foreign terms banana andplantain. The common name pisang inMalaysia and Indonesia, saging inPhilippines, kluai in Thailand, chouiin Vietnam and chiao in China are ap-plicable to all dessert and cooking ba-nanas, including plantain.

Important banana cultivars inSoutheast AsiaThe center of origin for bananas is alsoits center of diversity. In SoutheastAsia, the consumers have a wide selec-tion of dessert and cooking cultivars.Banana varieties vary in colour, size,shape and utility. The important com-mercial cultivars in Southeast Asia arepresented in Table 1.

Banana production systemsBanana production in Southeast Asiahas been classified into four systems.The most common is backyard produc-tion and the farmers grow bananas pri-marily for home consumption. Thechoice of cultivars grown depends onfamily requirements whether dessertor cooking bananas, quality prefer-ences of household members and easeof production. In the backyard produc-tion system, labour is entirely suppliedby family members. No commercialfertilizers nor pesticides are used, onlycompost and animal manure are ap-plied.

The second most popular is themixed-crop production system. InSoutheast Asia, the fruit industry isprimarily a smallholder enterprise and

bananas are grown with other cropcommodities. In the mixed-crop pro-duction system, bananas can be theprimary crop or only a secondary crop,the permanent crop or a temporarycrop. A common practice in SoutheastAsia is to plant banana as nurse cropto shade-loving plants such as cacao,coffee, black pepper, nutmeg, etc. Butin some cases, banana is the cropgrown under the shade of taller plantsas in coconut plantations. In Malaysiaand southern Philippines where plan-tation crops are extensively grown, ba-nana is often planted as a temporaryintercrop to the young rubber and oilpalms. The bananas provide incomeduring the non-productive stage of thepermanent crop. Once the primarycrop becomes established and the ba-nanas interfere with the rubber or oilpalms, the bananas are eliminated. Insome parts of the Philippines, co-conuts, bananas, papayas and pineap-ple are grown in the same area under amulti-storey combination. A banana-based cropping system highly recom-mended in Southeast Asia is to plantshort duration crops between the rowsof newly planted banana.

An emerging popular production sys-tem is the commercial small-holderplantation where bananas are grownas a monocrop in areas ranging from 2to 20 ha. This production system isproliferating near population centerswhere market demand is strong andsteady. The selection of cultivars togrow is dictated by consumersÕ prefer-ences, prevailing agroclimatic condi-tions and pest and disease situation.In the commercial smallholder planta-tions, the farmers apply commercialfertilizers and pesticides. They alsohire labour to control weeds and insome locations to irrigate the farm.

Large commercial banana planta-tions that grow fruit for the exportmarkets are also found in SoutheastAsia, specifically in the Philippines.These modern corporate-farms caterto the exacting requirements of the ba-nana export trade. Corporate farmsare capital intensive and involve heavyinvestments in plantation infrastruc-ture. Production practices are appliedat optimum levels and productivity isvery high. Quality of the produce is ofprimary consideration.

Banana production under adverseenvironmentsThe most serious climatic problemthat confronts commercial producersof banana in Asia and the Pacific arethe tropical storms and typhoons. Ba-nanas are sensitive to strong winds,especially for tall cultivars bearing a


heavy bunch of fruit. Storms at 54 to 72 kph cause serious blowdowns and ty-phoons at more than 72 kph can result incomplete destruction of banana planta-tions. Taiwan, South China, Vietnam,northern and central Philippines andmany island countries in the South Pa-cific are annually subjected to thiscalamity. But the occurrence of typhoonsis seasonal and it coincides with themonsoon months. After consistently suf-fering heavy losses caused by tropicalstorms and typhoons that occur with pre-dictable regularity, the banana growersin Taiwan and the Ilocos region in north-ern Philippines have adapted a plantingcalendar with corresponding plantationmanagement practices that ensures min-imal damage caused by strong winds(Valmayor et al. 1998). In the case ofnorthern Philippines, the tropical cy-clones begin in June and cease in No-vember with highest frequency duringthe months of July, August and Septem-ber. To avoid damage caused by windstorms, planting is scheduled in May sothat the bananas are still small and dam-age is minimal when the typhoons passover the region. The monsoon rains de-cline in November and so with the ty-phoon season only to reappear in Junethe following year. With irrigation, plantgrowth and development continue andflowering takes place in late February orearly March and the fruit bunches ma-ture in April or May, one year after plant-ing. Harvesting is completed before theonset of next year’s stormy weather. Theresultant effect of the strict adherence tothis cropping system is the annual crop-ping of bananas. After harvest time, sup-ply becomes very scarce but bananafarmers avoid heavy losses due to ty-phoons. It is important that only culti-vars that mature in 12 months or less areselected for this cropping system. Allsuckers that sprout from July to Januaryshould be removed as allowing them todevelop will only subject them to winddamage the following typhoon season.The suckers that develop after floweringwill be allowed to grow, but only one, themost vigorous will be nurtured to replacethe mother plant and start a secondcropping cycle. To compensate for har-vesting only one fruit bunch per mat per12 months cycle, a closer distance ofplanting at 2x2 meters is recommended.

In Thailand, flooding is a serious prob-lem on the flood plains around Bangkok,particularly during the rainy season. Toovercome the problem of high watertable and poor drainage, the farmersgrow bananas on beds or ridges con-structed between drainage canals. Thebeds measure 2 to 3 meters wide and sev-eral meters long and are built-up by de-positing the soil dug from canals along-

side the raised beds. Rows of bananasare planted once the beds are 1 meterabove the canal water level. Vietnamesefarmers in the Mekong River delta, par-ticularly those close to Saigon also growbananas on raised beds. The more pro-gressive growers in both countries drainthe excess water through volume pumpsduring the monsoon season and drawwater from the canals to irrigate theirbananas during the dry season.

Other natural calamities confrontingbanana growers in Southeast Asia aredroughts and volcanic eruptions. In east-ern Indonesia, the western parts ofLuzon and the Visayas in the Philippineswhere the dry season is long extended,the drought tolerant varieties of purebalbisiana genome composition (BBB)such as Pisang Kepok, Saba and Cardabaare planted while in the dry areas ofThailand and Malaysia, a hybrid withABB genome constitution locally knownas Kluai Namwa or Pisang Awak is the fa-vorite cultivar. The banana farmers inthe region are helpless against volcaniceruptions but fortunately, occurrence israre and the area affected is generallynot as extensive as calamities caused bytyphoons and droughts.

Processing and utilizationof bananaBananas are primarily traded in freshform and consumed as such. However,cooking bananas and plantains make ex-cellent chips, a popular snack item in

Southeast Asian countries. The Philip-pines is the biggest world exporter of ba-nana chips amounting to some US$22million per year. Thailand and Indonesiahave also developed export markets forbanana chips. Other major processedproducts derived from banana are ba-nana catsup and bottled baby food. �

ReferencesCheesman J. 1948. Classification of the bananas.

III. Critical notes on species (c) Musa paradisi-aca Linn. and Musa sapientum Linn. Kew Bull.2: 145-154.

Greuter W. (ed.). 1994. International code of botan-ical nomenclature. Koeltz Scientific books,Konigstein, Germany.

Karamura D.A. 1998. Numerical taxonomic studiesof the East African Highland bananas (MusaAAA-East Africa) in Uganda. The University ofReading, UK.

Simmonds N.W. & K. Shepherd. 1955. The taxonomyand origins of the cultivated bananas. J. Linn.Soc (Botany) 55: 302-312.

Valmayor R.V., B. Silayoi, S.H. Jamaluddin, S.Kusumo, R.R.C. Espino & O.C. Pascua. 1991. Ba-nana classification and commercial cultivars inSoutheast Asia. PCARRD Info. Bull. 24. LosBaños, Philippines.

Valmayor R.V., D.D. Ignacio & G.S. Pascua. 1998.Banana production in the typhoon prone regionof Ilocos, Philippines. RISBAP Bull. 2(2).


The author is Honorary Research Fellow, INIBAP.

Table 1. Important commercial cultivars of banana in Southeast Asia.

Country Dessert varieties Cooking varieties

Indonesia Pisang Ambon Putih Pisang Kepok

Pisang Ambon Lumut Pisang Oli

Pisang Raja Sereh Pisang Kosta

Pisang Raja** Pisang Tanduk*

Pisang Barangan Pisang Nangka*

Pisang Mas

Malaysia Pisang Masá Pisang Awak

Pisang Rastali Pisang Raja**

Pisang Embun Pisang Nangka*

Pisang Berangan Pisang Tandok*

Pisang Masak Hijau Pisang Nipah

Pisang Lemak Manis

Thailand Kluai Hom Thongá Kluai Namwa**

Kluai Khai Kluai Hakmuk

Kluai Lep Mu Nang Kluai Som

Vietnam Chuoi Tien Chuoi Mat

Chuoi Tieu Chuoi Sap

Chuoi Tay Chuoi Ngu

Chuoi Bom

Philippines Lakatan Saba

Latundan Sabang Puti

Buñgulan Cardaba

Inarnibal Turangkog

Amas Matavia

Morado Tindok*

Giant Cavendishá Laknau*

Grande Naine**** Plantain, **Eaten fresh or cooked, ***Export variety.


Review article

Which banana variety should I grow?Jeff Daniells

In Australia and elsewhere, there isa growing interest in alternativebanana varieties. This is largely

driven by:1)Emergence of new diseases/new

strains of exotic diseases2)Desire to reduce pesticide usage3)Development of niche markets.

The Queensland Department of Pri-mary Industries in Australia has evalu-ated the agronomic and disease resis-tance characteristics of hundreds ofvarieties over the past 15 years. It hasbecome fairly clear from these studiesthat there is no ‘perfect’ variety – onethat is resistant to all pests and dis-eases, yields high, is good to eat andhandles well. Each variety has its ownadvantages and disadvantages. This ar-ticle attempts to provide useful infor-mation about the better varieties iden-tified by QDPI. Readers shouldhowever bear in mind that the solutionto their production problems may notjust lie with improved genotypes.Holistic integrated crop managementapproaches also have much to offer(Daniells 1998).

ChecklistTable 1 is a checklist of the better vari-eties with their relative positive andnegative characteristics listed. Itshould be noted that varietal re-sponses can vary according to the envi-ronment they are grown in, and thestrains of diseases they are exposed to.

Whether a variety is suitable fordessert or cooking purposes is gov-erned largely by cultural preferences.Varieties suitable for evaluation forparticular circumstances can be de-duced from the checklist.

Additional NotesYieldMost variety alternatives to Cavendishare lower yielding than Cavendish.Therefore, if they are grown for localor export markets, they must com-mand better prices and/or be cheaperto produce than Cavendish. Some vari-eties, e.g. Sucrier, are very quick cy-cling, but this still does not make upmuch for their lower bunch weights.

Wind susceptibilityAs a general rule, dwarf varieties aremore resistant to wind damage and arealso easier to support with props ortwine. Dwarf varieties are also easierto manage for leaf disease, bunchpests, bunch trimming, bunch coveringand harvesting. Unfortunately dwarfvarieties tend to be more prone to‘choke throat’ and they are sometimesassociated with smaller fruit. Furtherstrategies to minimise losses fromwind are detailed by Daniells (1991b).

PurposeVirtually all varieties of bananas andplantains may be either eaten rawwhen ripe (dessert) or cooked wheneither green or ripe. Cultural prefer-ences govern the choices made. Many‘new’ varieties have still to be evalu-

ated for a wide range of potential pur-poses.

SigatokasThe severity of disease depends uponthe resistance or susceptibility of thevariety, the intensity of infection, envi-ronmental conditions and the ‘strain’of the pathogen present. Disease inci-dence will be greatest under hot wetconditions with high inoculum levels.TU8 (T8) was originally highly resis-tant to black Sigatoka in the Cook Is-lands (Fullerton 1990) but new strainsof the disease have since rendered this

The dwarf stature of Dwarf French Plantainfacilitates management.

Table 1. Variety plant characteristics and disease resistance checklists.

Genome Variety Synonyms/Subgroup Plant characteristics Disease resistance

Purpose Yield Wind Stature Comments BS YS Fusarium wilt(1) Commentssusceptibility

Race 1 (2) Race 2 Race 4

AA Sucrier Pisang Mas D L PR I S (3) S R R SKluai KhaiAmasFigue Sucrée

Inarnibal Pisang Lemak Manis D L PR n R S R R SPisang Berlin

Lakatan (4) Pisang Berangan D L-M S I Long green life VS VS R R S

AAA Dwarf Red Figue Rose Naine D M R (5) n Some choke S S S R Sthroat problems

J.D. Pisang Kapas? Ibota D/C M PR I HR HR R R S R to burrowingYangambi nematode and

banana weevilborer

Kluai Khai Bonng D L-M VS I Very active R? HR R R S R tofruit banana weevil

borer

Williams Cavendish D H S dw Long green life VS VS R R S


Table 1. continued

Genome Variety Synonyms/ Plant characteristics Disease resistanceSub group

Purpose Yield Wind Stature Comments BS YS Fusarium wilt(1) Commentssusceptibility

Race 1 (2) Race 2 Race 4

AAAA T6 61-86 Highgate hybrid D M-H S I R HR R R S

T12 Buccaneer, 65-168-12, D M-H S I R R R SHighgate hybrid

SH-3436 Highgate hybrid D H S I R S R R S

SH-3444 FHIA-23, Highgate hybrid D H S I R S R R S

SH-3649 FHIA-17, Highgate hybrid D H S I R S R R S

SH-3486 FHIA-02, Mona Lisa D M-H PR I HR S? S R SWilliams hybrid?

AAAB SH-3480 FHIA-18, Pome hybrid D M-H PR I HR R? R R R

SH-3481 FHIA-01 Goldfinger, D M-H PR I HR S R R R(6) R to burrowingPome hybrid nematode

SH-3640.10 High Noon, Pome hybrid D M-H PR I HR VS R R R

SH-3697 Maqueño hybrid C M-H S? T R R? S R S

PC 12.05 Pome hybrid D L-M PR T S R R R S

PA 03.22 Pome hybrid D L-M R I S R R R S

AAB Silk Apple, Pisang Raja Sereh, D L-M PR I S S S S SPisang Rastali, Latundan, Sugar, Figue Pomme, Manzano

Pisang Ceylan Mysore (7) D M S T R R S (8) R S(8)

Pisang Raja D/C L-M S T S S R R S

Prata Anã Santa Catarina Prata, D L-M VR I Short green life VS S S R SPome 9), some

choke throat problems

J. D. Finger Rajapuri ?, Pome D L-M VR dw some choke VS S S R Sthroat problems

Lady Finger Pome D L-M R I VS S S R S

Pacific Maia Maoli/Popoulu C M R I Long green life S S S R SPlantain

Mangaro Maia Maoli/Popoulu C M PR T S S S R STorotea

Dwarf Plantain C L-M R(5) dw S R R R S VS to bananaFrench weevil borerPlantain

Horn Tanduk, Pisang C L-M S I S R(10) R R S VS to bananaPlantain Tandok, Plantain weevil borer

ABB Kluai Pisang Awak D/C M R(5) dw Some dummy HR HR S R SNamwa finger(11)

Khom problemsShort green life

Pisang Awak Ducasse, Kluai Namwa D/C M PR T Short green life HR HR S R S

Bluggoe C L-M PR I R HR R S S

Blue Java Ney Mannan D/C L-M PR I R HR R S S

Fa’i Afa Saba C L-M PR T R HR S R S

Gubao IMTP Phase 2 ‘Saba’ C M S I R HR S R S

Kandrian Simoi C L-M PR T R HR R? R S

AABB SH-3565 FHIA-03 C M-H S I R S? S R S

Abbreviations used:

Purpose: D = dessert; C = cooking

Yield: L = low; M = moderate; H = high

Wind susceptibility: VS = very susceptible; S = susceptible; PR = partially resistant; R = resistant

Stature: dw = dwarf; I = intermediate; T = tall

Disease resistance and related comments: BS = black Sigatoka; YS = yellow Sigatoka; VS = verysusceptible; S = susceptible; R = resistant; HR = highly resistant.

Notes

(1) New races can develop/= usual reaction

(2) VCG groups vary particularly Race 1 types vs. varietal pathogenicity

(3) IMTP 1 was borderline on susceptible – resistant but Sucrier has certainly been resistantunder some circumstances (Jones 1993)

(4) There are reports that some Lakatan may be AAA

(5) Benefits from bunch support

(6) Reported by INIBAP as tolerant but questionable

(7) Superficially the same

(8) Sometimes ratoon resistance

(9) Short green-life during environmental stress e.g. cool temperatures/wet season

(10) Susceptible under some circumstances (Daniells and Bryde 1999)

(11) Some fingers do not properly fill out.

variety susceptible in that environ-ment.

Black Sigatoka is present in manyproducing countries but some majorproduction areas, such as parts ofBrazil, Australia, parts of SE Asia andhigh altitude tropical areas such as inCameroon are still free of this disease.

In those areas yellow Sigatoka remainsthe most important leaf disease.

Fusarium (Foc)The different races of Fusarium shownin the checklist are based on thehost–pathogen interaction. Althoughduring the last decade, isolates of Foc

have been genetically characterised inseveral different ways, race is stillused by many to distinguish patho-genic variation in the fungus. Tradi-tionally, four races of Foc are recog-nised. Races 1, 2 and 4 affect bananas,while Race 3 affects Heliconia and isonly weakly pathogenic in banana. It


should be noted that, to date, thereare very few varieties known to be re-sistant to Foc Race 4. Quarantine is ex-tremely important for stopping furtherspread of this pathogen.

Various races of Fusarium wilt arepresent in most banana-producing re-gions of the world but the disease isnoticeably absent from the South Pa-cific. Hybrids from breeding pro-grammes, which may be rejected be-cause of susceptibility to Fusariumwilt, could in fact be very useful inplaces such as the South Pacific whereresistance to Fusarium wilt is cur-rently unimportant. An example of thisis SH-3697 – a high yielding Maqueñohybrid resistant to black Sigatoka butsusceptible to Foc Race 1.

It should be noted that there aregradations of resistance to Fusarium.For example Lady Finger (AAB, Pome)is much less susceptible to Foc Race 1than Sugar (AAB, Silk) in the northQueensland environment. Environ-mental conditions can also influencethe severity of the disease reaction.

Finger dropSome varieties are very prone to fin-ger drop during ripening, and thishas restricted the adoption of newhybrids in some areas in the past(Marriott 1980). However, the sus-ceptibility of varieties to finger dropcan be minimised by varying theripening conditions, including theuse of lower temperatures, and thestage of maturity at which fruit isharvested (Paull 1996, Seberry andHarris 1998).

Fruit greenlifeSufficient transport/storage life of fruitis particularly important for export sit-uations. One of the great virtues ofCavendish-type bananas is their longgreenlife when properly managed.Some other varieties are not so wellsuited for export marketing. However,techniques such as modified atmos-phere packaging and good manage-

ment can help overcome such prob-lems (Daniells 1991a).Niche markets

The following varieties have beenidentified as having potential for nichemarkets in Australia as well as for ex-port:• Sucrier• SH-3697• Dwarf French Plantain• Lakatan• Silk• Horn Plantain• Dwarf Red• Pisang Ceylan• Kluai Namwa Khom• Kluai Khai Bonng• Prata Anã• Pisang Awak• SH-3480 (FHIA-18)• Pacific Plantain• Fa’i Afa �

ReferencesDaniells J.W. 1991a. How to avoid mixed ripe prob-

lems with bananas. Queensland Fruit and Veg-etable News 62(4): 12-13.

Daniells J.W. 1991b. How to minimize losses due towind damage in bananas. Queensland Fruit andVegetable News 62(13): 14,15,20.

Daniells J.W. 1998. Integrated crop management forsustainable banana production. Pp. 67-76 in Pro-

ceedings 8th INIBAP-ASPNET Regional AdvisoryCommittee Meeting, Brisbane 21-23 October, 1998.

Daniells J.W. & N.J. Bryde. 1999. Screening of 143banana varieties for resistance to yellow Sigatokain North Queensland. InfoMusa 8(1): 15-21.

Fullerton R.A. 1990. Studies of Mycosphaerella fi-jiensis Morelet in the Pacific Islands. Pp. 29-37 inSigatoka leaf spot diseases of bananas: Proceed-ings of an international workshop held at SanJose, Costa Rica, March 28-April 1, 1989 (R. AFullerton & R.H. Stover, eds). INIBAP, Montpel-lier, France.

Jones D.R. 1993. Evaluating banana and plantain forreaction to black leaf streak disease in the SouthPacific. Tropical Agriculture (Trinidad) 70:39-44.

Marriott J. 1980. Bananas - Physiology and biochem-istry of storage and ripening for optimum quality.Critical Reviews in Food Science and Nutrition 13:41-88.

Paull R.E. 1996. Ethylene, storage and ripening tem-peratures affect Dwarf Brazilian banana fingerdrop. Postharvest Biology and Technology 8: 65-74.

Seberry J.A. & D.R. Harris.1998. Postharvest evalua-tion of FHIA-01 and other new banana varietiesfor subtropical Australia. Pp. 537-546 in Proceed-ings of the First International Symposium on Ba-nana in the Subtropics (V. Galán Saúco, ed.)Acta Horticulturae 490.

The author works at The Queensland Department ofPrimary Industries (QDPI), PO Box 20, South John-stone Q 4859, Australia.

Lakatan is the most popular dessert variety ofthe Philippines.

J.D. Finger is very resistant to wind damage.

Errata in previous issue (InfoMusa Vol. 8, No. 2)• Evaluation of bananas for niche markets in subtropical Florida:

p. 17, at the bottom of Table 1, Fe’i banana Rimina should appear inboldface and be separated from the above section (AABB genome) towhich it does not belong; and p. 18, at the end of first column/top ofsecond column, the passage “…differences between two clones of‘Ney poovan’, one of which, ‘Sukali ndizi’, develops symptoms moreslowly than the other, ‘Kisubi’...” should read “…differences betweentwo clones of ‘Ney poovan’, one of which, ‘Kisubi’, develops symptomsmore slowly than the other, ‘Sukali ndizi’…”.

• Musa clones in Peru: classification, uses, production potentialand constraints: p. 22, Figure 3, the scale of the right y-axis hasbeen omitted. The correct version of the figure is given at right.

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Asia and the PacificThe Food and Fertilizer Technology Centre in Taiwan publishes an Extension Bulletin on the production of virus-free banana plantlets in TaiwanThis bulletin discusses the use of ba-nana plantlets produced by tissue cul-ture in Taiwan. The tissue culture pro-gramme for banana began in 1983.Originally started to produce plantletsfree of Fusarium wilt, the programmeis now used to ensure that bananaplanting materials are free from virus.A total of 26 million plantlets havebeen produced under the programme.The Bulletin describes the productionsystems for tissue-cultured plants anddiscusses the benefits and disadvan-tages, such as the susceptibility to her-bicide damage, of using this type ofplanting material. Finally the bulletindescribes a series of cultural methodsto protect disease-free plantlets fromvirus re-infection in the field. The Bul-letin describes how tissue culturetechnology can be effective and feasi-ble for smallholders, provided the nec-essary technical support is available.The Bulletin is based on a paper firstpresented at an international seminaron ‘Disease Management of Bananaand Citrus: The use and managementof disease-free planting materials’ heldin Davao City, Philippines, on October14-16, 1998.S.C. Hwang and H.-J. Su, Extension Bulletin 460,Food and Fertilizer Technology Centre, Taiwan,November 1998.

TBRI, Taiwan provides new bananavarieties to INIBAPThe Taiwan Banana Research Institute(TBRI) recently provided two new ba-nana varieties to INIBAP. The two vari-eties are somaclonal variants ofCavendish, selected by TBRI re-searchers as being high-yielding andresistant to subtropical race 4 ofFusarium wilt disease. The varieties,GCTCV-106 and GCTCV-247 arepresently being virus-indexed by INI-BAP. Once indexing is completed, INI-BAP will be making these varietiesavailable for world-wide evaluation.

Banana corm rot in north Queensland,AustraliaA new form of corm rot has recentlybeen identified on several bananaplantations in north Queensland. Inaddition, a finger rot disease calledMokillo, which occurs occasionally inthe region, has also been identified.Banana corm rot appears to be en-demic in north Queensland and haspreviously been described as butt rot

caused by Erwinia carotovora subsp.carotovora. Recently the bacteria E.chrysanthemi , E. chrysanthemisubsp. carotovora and E.c. subsp.atroseptica have been identified frombanana heart rot and corm rot samplesfrom several plantations in the region.The symptom severity appears to becorrelated with the Erwinia speciesassociated with the infected tissue.This observation suggests that cormrot is probably caused by E. chrysan-themi and E.c. subsp. atroseptica,whereas heart rot is mainly caused byE. c. subsp. carotovora.

In the case of banana finger rot(Mokillo), the bacteria E. chrysanthemihas been successfully isolated from fin-ger rot samples and pathogenicity hasbeen established in banana fruits underlaboratory conditions.

This is the first report of E.c. subsp.atroseptica in bananas and on theability of E. chrysanthemi isolatesfrom corm rot to cause Mokillo.Source: Australian Bananas Vol. 8, Dec. 1999,Australian Banana Growers’ Council Inc.

Biological control of nematodes couldbecome a realityResearchers in Queensland, Australiahave identified potential fungalpathogens of banana nematodes. Fol-lowing the screening of soil samplesfrom tropical and sub-tropical areas inQueensland and New South Wales, itwas discovered that nematode multi-plication in the roots of tissue-culturedbanana plants was significantly less inplants grown in some untreated soilsthan in sterilised soils. Fungi ex-tracted from the roots of the bananaswere shown to reduce the numbers ofburrowing nematodes in pots by 80%.Although much further research is stillneeded to develop an acceptablemethod of biological nematode con-trol, the potential for a successful out-come of this work seems to be good.Source: Bananatopics, Vol. 27, June 1999.

Studies on fixing critical limits of K, Naand K/Na ratio for bananas in saline-sodicsoil conditionsIn some areas of India, bananas aregrown in soils which are classified as“saline-sodic”. In such soils bananassuffer from salt injury, which causesexternal symptoms of marginal chloro-sis of the leaves and results in signifi-cant yield reduction. In most saline-sodic soils, K/Na ratios are less thanone. But in a K-loving crop such as ba-nana, K/Na ratios greater than one areessential.

Fifty soil samples from the rhizos-phere and corresponding banana planttissue samples were collected ran-

domly from saline-sodic soils of the Na-tional Research Centre for Bananas(NRCB) farm and from neighbouringfarms. The exchangeable K and Na inthe soils ranged from 0.31 to 2.54cmol/kg and from 1.74 to 6.78 cmol/kgrespectively. The corresponding yield(bunch weights) were also collected atharvest. The soil and tissue sampleswere analysed for Na and K concentra-tions by flame photometer and K/Naratios calculated.

Correlation coefficients and linearregression equations were calculatedfor soil and plant K, Na and K/Naagainst yield. The results obtained in-dicated that yields gradually increasedwith increasing Na up to a level of 480ppm in the soil and 0.47% in the planttissue. Above this limit, Na had a nega-tive effect on yield. Similarly, the criti-cal limits of soil and plant K concen-trations were fixed at 710 ppm and2.82% respectively.

In conclusion therefore, for optimumyield in saline-sodic soils, the soil shouldhave at least 710 ppm K, not more than480 ppm Na and the soil K/Na ratioshould be at least 1.46. At the sametime, the leaves of the banana cropshould maintain at least 2.82% K, notmore than 0.47% Na and the leaf K/Naratio should not be less than 5.7.More information is available from: K.J.Jeyabaskaran, NRCB, Vayalur Road, Trichy 620-017, Tamil Nadu, India.

Medicinal weeds in banana orchards inChhattisgarh, IndiaWeed infestation is one of the majorconstraints to high yields in banana or-chards in Chhatisgarh. Farmers gener-ally adopt hand weeding and chemicalweed control methods for weed man-agement. However, increasing labourcosts and the demand for more organicproduction methods has resulted in asearch for innovative methods forweed management. A series of studieswere conducted between 1994 – 2000by the Department of Agronomy, In-dira Gandhi Agricultural University,Raipur. The studies included:• Identification of existing weed flora

of banana orchards• Listing the medicinal, allelopathic

and industrial potential of commonweeds

• Searching the potential market for‘useful’ weeds.The study revealed more than 60

weeds with well documented medici-nal, industrial or allelopathic uses in-festing banana fields. In particular, 10species were found to be abundant inall districts surveyed, all of which pos-sessed medicinal industrial or allelo-pathic uses (Table 1).

MusaNews

The study on marketing aspects re-vealed that these weeds are indeedvaluable and more than 300 nationaland international herbal retailers areeager to purchase these weeds at rea-sonable prices. The study also revealedthat after uprooting the weeds throughhand-weeding, and after collecting,processing and selling the parts withthe help of village cooperative soci-eties, farmers can earn additional in-come and recover the cost of hand-weeding.

Effect of post-harvest manipulation ofparent pseudostem in the productivity ofratoon crop in bananaAn experiment was carried out by re-searchers at the Agricultural Univer-sity (Bidhan Chandra KrishiViswavidyalaya) of West Bengal to in-vestigate the effect on the first ratooncrop of retaining the parent pseu-dostem after bunch harvest at differ-ent heights. The treatments investi-gated were as follows:• Cutting height of parent pseu-

dostem:– Un-topped– Cut at mid-height– Cut at corm level.

• Retention of suckers:– One sucker per matt– Two suckers per matt.Retention of the un-topped parent

pseudostem resulted in an increase inthe height and girth of the followersucker, as well as an increase in thesize of fingers and the number ofhands/bunch. However this treatmentalso delayed harvest by 9 days com-pared to cutting the parent pseu-dostem at ground level. The retentionof two suckers delayed shooting by 17days, but also resulted in an increasedyield. Indeed the highest yield of alltreatments (187.6 t/ha) was producedby a combination of two suckers permatt attached to an un-topped motherplant.Further information available from: Md AbuHasan, B. Mathew and P.K. Chattopadhyay,Faculty of Horticulture, Agriculture University,Mohanpur, West Bengal, India.

West and Central AfricaThe use of mycorrhizae in the control ofbanana nematodesBanana nematodes are one of themain constraints to banana and plan-tain production in West and CentralAfrica. Researchers at CRBP havebeen working on banana nematodesfor many years, and this research hasallowed the principal nematodespecies to be identified and strategiesto control these have been developed.In Cameroon, the main parasiticspecies at low altitude is Radopholussimilis, while Pratylenchus goodeyibecomes more important at altitudesabove 1000 m. Recent research has fo-cused on the use of mycorrhizae (ofthe genus Glomus) isolated inCameroon, to improve the tolerance ofplantains to the two nematode species.Research trials using the plantain cul-tivar Batard have focused on the per-formance of both tissue culture andsucker-derived plants, inoculated withthe mycorrhizae before field planting.Trials were carried out at both low andhigh altitude sites.

All plants inoculated with mycor-rhizae at both sites showed an in-creased root mass and higher plant drymatter content than un-inoculatedplants. Furthermore, the presence ofthe mycorrhizae resulted in a reduc-tion of up to 75% of the population ofnematodes in the roots of inoculatedplants.Information from Le Courrier du CRBP, No. 65.

Export of plantains to EuropeThe transport of plantains from WestAfrica to the European markets ispresently by air. This is expensive andreduces significantly the profit marginfor producers. Researchers at CRBPhave therefore been investigating thepossibilities of conserving plantainfruit at low temperature to allow themto be exported by ship (a journey ofaround 15 days). Tests were carriedout on the varieties French Clair, Bâ-tard and Big Ebanga. Fruit were col-lected at various harvest stages and,

following fungicide treatment andpacking in cartons, the fruit wasstored at ambient temperature (25-30°C, 80 – 90% RH) for two days, thenplaced in a cold chamber (12-14°C, 85-95% RH) for 15 days.

The harvest stage which allowed thefruit to be conserved green for 15 days,without any noticeable decline in qual-ity occurred about one week before thefirst appearance of a ripening fingeron the first hand of French Clair, be-tween one to two weeks for Big Ebangaand two to three weeks for Bâtard. Thefruits of the latter two varieties seemto be most suited for the export mar-ket, in terms of quality and size.Source: PlantainInfo No. 39, Oct.-Nov. 1999.

Postharvest handling of bananas andplantains in the rural areas of Enugu state,NigeriaPoor postharvest handling of bananasand plantains often results in a signifi-cant loss of income for rural populations.It was observed that banana and plan-tain traders in Nsukka agricultural zonein Enugu State of Nigeria sell fruits thathave good physical and ripening quali-ties. A study was therefore carried out todetermine traditional handling tech-niques practised by three communitiesin this area involved in banana and plan-tain marketing. Information was ob-tained from 90 women using a structuredquestionnaire. The results showed thatalmost all the respondents were usingtraditional handling techniques whichreduced postharvest losses. The methodsemployed included:• Extension of green life of the fruit in a

fresh and firm state by daily mistspraying of cold water on the fruitmorning and evening.

• Ripening of fruit using Irvingiasmithii or I. gabonensis. (Bananas areplaced inside plastic bags with Irvin-gia fruit and kept sealed for a periodbetween 24 and 72 hours, dependingon outside temperature.)

• Transport of fruit using baskets linedwith leaves to prevent transit injury.

Respondents also highlighted the needfor a ‘banana house’ for storing fruit,located in the coolest area possible.Such a storage area was reported to re-duce the temperature around the fruitwhile increasing the relative humidityof the surrounding area. Handlingmethods practised also included theimmediate de-handing of the bananabunch and placing fruit inside the ba-nana house as soon as possible.The techniques used are simple and ef-

fective and could be readily adapted inother regions.Further information available from: K.P. Baiyeriand C. Alor. Department of Crop Science,University of Nigeria, Nsukka, Nigeria.


Table 1. Medicinal uses of 10 common weeds in banana orchards of Chhattisgarh.

Scientific name Common name Medicinal use

Cyperus rotundus Motha Root is useful in leprosy, thirst, fever, blood diseases, nausea, dysentery, intense itching, epilepsy, opthalmia

Parthenium hysterophorus Gajar ghas As a homeopathic drug to cure respiratory problems

Ageratum conyzoides Mahkua For skin problems

Euphorbia sp. Duddhi For respiratory problems

Chenopodium album Bathua For hook worms, Leucoderma

Blumea lacera Kukurmutta For bronchitis, fevers, thirst and burning sensations

Achyranthes aspera Latkana As stypic, antivenom; in diseases of the digestive system

Calotropis gigantea Fudhar For rheumatism and reproductive organ diseases

Datura stramonium Datura For respiratory problems

Jatropha curcas Ratanjot In diseases of the digestive, respiratory and reproductive systemııs

Economic benefits of IPM in GhanaIITA researchers have been introducingthe corm-paring technique as a methodof nematode/weevil control to farmersin Ghana. Since the introduction of thetechnique in 1993, 40% of farmers haveadopted it. It was found that the adop-tion of clean planting material togetherwith improved management practiceswas profitable over a 3-year period, re-sulting in returns of US$1300 perhectare, equivalent to US$475 increasewhen compared to farmers’ traditionalpractices.Source: IITA Annual Report, 1998.

Latin America and the CaribbeanBlack Sigatoka spreads to HaitiFollowing the report in INFOMUSA8(2) that black Sigatoka posed a threatto banana production in Haiti, the dis-ease has now been identified there(FruiTrop 67). CIRAD-FLHOR re-searchers are expecting very soon toconfirm the identification of the dis-ease, which appears to have crossedthe northern border of Haiti following amarked rainy season at the end of 1999.For more information, contact: Thierry Lescot,[email protected]

Effect of liquid humus produced byearthworms (Eisenia foetida) on thegrowth of ‘Pineo gigante’ banana stumps(Musa AAA)The establishment of the initial popula-tion of a crop is a most important stepwhich will determine good yields. It isessential to select good quality seedand make sure that the availability ofwater and nutriments in the soil is ade-quate to allow a fast and uniform initialgrowth of the plants (Roberts 1997).

Soil fertility may be preservedthrough different mechanisms linked toorganic matter and through which mi-croorganisms (fungi, bacteria, proto-zoa, algae, etc.) play an important rolein the nutriments’ mineralization andstabilisation processes. These microor-ganisms may themselves, in certainconditions, function as reservoirs whichwill avoid loss of nutriments due toleaching, volatilisation and/or fixationon humic or inorganic compounds.

These multiple biological processes,in which roots, microorganisms and soilcomponents interact, make inorganic(ionic) compounds available to plants.Incorporation of organic compounds inthe soil increases the quantity and ac-tivity of soil microorganisms; this sug-gests managing organic and inorganicfertilisation in commercial plantationsas a relatively ecological and economi-cal alternative (Pineda 1996, Sikoracited by Fernández et al. 1998). More-over, the use of inorganic fertilisersleads to a transitory destruction of the

soil microbial population, which can berestored by the use of organic fertilis-ers (Pineda 1996). It is very importantto make use of the available knowledgerelated to soil biological processes andmineralization of labile organic com-pounds. These play an essential role inthe development of a profitable and en-vironment-friendly agriculture, inwhich the inoculation of microorgan-isms active at rhizosphere level takeson vital importance (Reyes et al. 1995).

However, organic sources are mostlyused as soil and/or foliage fertiliser forplants which are already establishedrather than as a pre-planting treatment.Stumps of the ‘Pineo gigante’ bananawere planted after immersion in a solu-tion of liquid humus produced by theearthworm Eisenia foetida, for differentconcentrations and immersion times.

Liquid humus has a positive effect onprecocious budding and on the growthrate of the stumps. The planting materialobtained with this pre-planting treat-ment is more homogeneous and strongerthan non-treated stumps. Indeed, thistreatment allows faster establishment ofthe plant and enables it to better exploitthe nutriments present in the soil solu-tion. Its type of action is not clearly ex-plained yet but it can already be inferredthat in a way or another, it activatesphysiological mechanisms which have anotable and direct influence on banana’sdevelopment and growth, as is expressedby plant vigour. It is important to con-duct further research on this subject andto study physiological aspects moreclosely.

ReferencesFernández M., C. Alvarez, A. Borges-Perez & A.

Borges-Rodriguez. 1998. Bacteria-enriched inoc-ulant enhances banana development and influ-ences nutrition. Fruits 53: 79-87.

Pineda R. 1996. A propósito de ecología, agriculturay fertilizantes. Instituto de la potasa y el fósforo(INPOFOS). Informaciones agronómicas 22: 9-13.

Reyes A., M. González, E. García, C. Rodríguez, R.Martínez R & P. González. 1995. Influencia de lamicorriza y una bacteria solubilizadora de fosfatoen el crecimiento y desarrollo de plantas micro-propagadas de banano. INFOMUSA 4(2): 9-10.

Roberts T. 1997. Papel del fósforo y el potasio en elestablecimiento de los cultivos. Instituto de lapotasa y el fósforo (INPOFOS). InformacionesAgronómicas 26: 1-4.

Preliminary results provided by Gustavo Martínez,Omar Tremont, Rafael Pargas and Edwuar Manzanilla,FONAIAP/CENIAP, Apartado postal 4663, Maracay2101, Venezuela.

Eastern and Southern AfricaSpread of black Sigatoka in the IndianOcean regionDuring the 1990s black Sigatokaspread from East Africa to the Co-moros archipelago, being confirmed in

Mayotte in 1995. The disease has sincespread to all the plantations on theseislands. The presence of the disease issuspected in Madagascar and samplesare presently being analysed byCIRAD-FLHOR for confirmation.Source FruiTrop 67, March 2000.

Banana streak disease is present inRéunionBanana was introduced in the island ofRéunion in about 1668 by Dutch seafar-ers (Rivals 1960). No indigenous varietieshave been listed but several cultivarshave been introduced since then. Theybelong to the Sucrier, Cavendish, Silk,Pome and Bluggoe subgroups. ‘FigueRose’ (Red sub-group), a few plantain va-rieties and a number of ornamental ba-nanas (Ensete sp., M. balbisiana, M.ornata, M. zebrina and M. velutina)are also grown in family gardens.

The most commonly cultivated clonesbelong to the Cavendish subgroup(‘Valéry’ and ‘Petite Naine’ and, more re-cently, ‘Grande Naine’ and ‘Williams’).Bananas belonging to the Silk and Pomesubgroups are usually planted at theedge of sugar cane fields and generateadditional income for households whenthe other varieties are not available onthe market. Semi-intensive fields arefound mainly on the north-east coast andin the south, where there is more rainfall(Anon. 1998). Average farm area doesnot exceed 2 to 3 hectares and a total ofsome 200 hectares is under banana (Figure 1), on an island with a popula-

tion of 750 000 inhabitants. It is esti-mated that Réunion has a total of 500hectares under banana, when isolatedmicro-fields are included (Agreste 1998).

Yields vary from 10 to 30 tonnes perhectare. Production is reserved forlocal consumption only.

The banana borer (Cosmopolites sordidus) is the main pest. Yellow andblack Sigatoka have not been observed.Attacks by Fusarium sp. have been ob-served on plants belonging to the Silksubgroup.


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Figure 1. Geographical distribution andhectareage of cultivated bananas.

Guy Blomme

Banana and plantain (Musa spp.)are important crops for thesmall-scale farmer in the humid

and subhumid tropical regions of the

world. Intensive breeding efforts areunderway in this crop but all focus onthe improvement of aboveground para-meters. Yet the Musa root system iscrucial for nutrient and water uptake,plant support and production of plantgrowth regulators. Past research on

Musa root systems was limited to highvalue export dessert bananas and fewinvestigations have been carried outon the root system of plantains, cook-ing bananas or Musa hybrids. There-fore, a comprehensive study of theMusa root system up to the first ratoon


Only ‘Petite Naine’ plants displaysymptoms of banana streak disease, withthe crinkling of portions of leaf and sub-sequent rosetting of the plant (Figure 2).Bunches are deformed and small. OtherCavendish subgroup bananas planted inthe same fields do not display symptoms.

This cultivar, whose local name is‘Gabou’, is rarely grown intensively, al-though its potential yield is satisfactoryin the climatic conditions of Réunion. Incontrast, it is often planted in fruit gar-dens.

A leaf sample was indexed at theCIRAD virology laboratory. Observationusing immuno-electron microscopy withthe polyvalent serum developed by Lock-hart against banana streak virus (BSV)revealed bacilliform particles (Figure 3).The banana plants concerned are there-fore infected by BSV.

This viral disease was first described inMorocco (Lockhart 1986) and then innumerous banana production zones andin the Indian Ocean area: Mauritius,Madagascar, East and southern Africa

and Australia (Caruana 1993). Bananaplants displaying these symptoms wereinventoried in all the cultivation areas inRéunion (see map). Most growers hadobserved these symptoms «for a very longtime» without relating them to the pres-ence of a disease. Indeed, the diseasedplants do not display any more visiblesymptoms such as necrosis or wilt.

The proportion of diseased plants inthe infected fields varies from 20 to 50%.Spread of the disease does not seem tobe related to an animal vector. No scalesare observed on the plants. As bananastreak virus is not spread by tools, itwould seem that the only way in which itcan spread is via the planting of infectedsuckers.

In collaboration with the RéunionPlant Protection Service (Service de laProtection des Végétaux), farmers arebeing informed of this manner of spreadof the disease, are trained in the identifi-cation of infected plants and are beingasked not to use diseased suckers for re-planting and at best to destroy diseased

mats by application of a systemic insecti-cide. The use of plants grown by tissueculture and indexed for BSV is also a rec-ommended method.

ReferencesAgreste. 1998. Données chiffrées DOM: Statistique

agricole annuelle et valeur de la production agri-cole année 1997. Ministère de l’Agriculture et dela Pêche. 48 pp.

Anon. 1998. Enquête fruitière. Chambre d’Agricul-ture de la Réunion. 27 pp.

Caruana M.L. 1993. Principales maladies du ba-nanier – Méthodes de lutte. Atelier Régional surles maladies virales et l’amélioration génétiquedu bananier. IRAZ, Gitega, 15-20/02/1993.

Lockhart B.E.L. 1986. Purification and serology of abacilliform virus associated with banana streakdisease. Phytopathology 76:995-999.

Rivals P. 1960. Les espèces fruitières introduites àla Réunion. 96 pp.

Figure 3. Bacilliform particles of BSV (x 29 000).Figure 2. Symptoms fo BSV on a banana leaf.

Contact : C. Lavigne. CIRAD-FLHOR, Station deBassin-Plat, BP 180, 97455 Saint-Pierre Cedex,Réunion.

Thesis

The interdependence of root and shootdevelopment in banana (Musa spp.) under fieldconditions and the influence of differentbiophysical factors on this relationshipPhD Thesis submitted at KUL, Leuven, Belgium, February 2000.

was executed. This involved the inves-tigation of 46 genotypes belonging toall Musa groups and ploidy levels toprovide background support for the ge-netic improvement of plantains andbananas.

The relationship between the rootand the shoot system of Musa plantswas assessed using correlation andprincipal component analysis. Strongpositive correlations were observed be-tween root and shoot growth of themother plant during the early and mid-vegetative phase. However, these cor-relations were less pronounced duringthe reproductive phase, most probablydue to enhanced root senescence andincreased competition between themother plant and its suckers (i.e. lat-eral shoots).

Growth curves were drawn for differ-ent root and shoot traits. The shoot-root ratio increased during the vegeta-tive phase. For example, the rootsystem of in vitro-derived plants com-prised up to 40% plant dry matter dur-ing the early vegetative phase but less

than 15% during the reproductivephase. Leaf area as well as root systemsize decreased during the reproductivephase.

Variability in root system size is re-quired to conduct a breeding pro-gramme aimed at root system improve-ment. An increase in root system sizewas observed with higher ploidy lev-els.Variability in lateral root traits be-tween genotypes could not be assesseddue to strong micro-environmental in-fluences on lateral root growth.

Shoot and root growth are influ-enced by the type of vegetative plant-ing material. For example, sucker-de-rived plants produced a larger rootsystem during the mid-vegetativephase compared to in vitro-derivedplants. This may be due to the largercorm size of the sucker-derived plant-ing material. The root system size ofplants at flower emergence was how-ever similar for both types of plantingmaterial.

Methods were developed for fastand non-destructive root system as-

sessment. Root traits were estimatedfrom easily measurable shoot para-meters. In addition, soil core sam-pling (assessing less than 3% of themat root system) could give adequateinformation on the root system sizeof a complete mat. This method re-quires only 5% of the time needed toexcavate and assess the root systemof the entire mat.

We observed significant effects ofsoil type, climate, nematode infesta-tion and leaf area reduction on theroot system size. For example, a nema-tode infection reduced the root systemsize up to 70% for susceptible geno-types. However, the reduction in shootgrowth was generally less than the re-duction in root growth. Nematode-sus-ceptible genotypes will thus have ahigh shoot-root ratio making them in-creasingly susceptible to toppling.

Results from this study provide anin-depth view on Musa root system de-velopment and growth, and should fa-cilitate the research programmes ofboth nematologists and breeders. �


Thaddée Musabyimana

Tests were conducted during theperiod May 1996 to Febru-ary 1999 in the laboratory at

ICIPE’s Mbita Point field station(MPFS) and in the farmers’ fields inwestern Kenya, a prime banana grow-ing area. Neem seed powder (NSP),neem kernel powder (NKP), neemcake (NC) and neem oil (NO) contain-ing 4000, 5500, 5800 and 850 ppm ofazadirachtin A, respectively, were usedas such or in aqueous form.

Laboratory experiments: in choicetests, 48 h after release, less than 30%of weevils settled under neem-treatedbanana while more than 50% settledunder untreated corms. In a feedingtest, weevil larvae caused little damageto the neem-treated corms while itcaused heavy damage to the untreated

ones. This indicates a strong an-tifeedant effect of neem on C. sordidus.Also, females laid 3-10 times fewer eggsin neem-treated than in the untreatedcorms. The egg hatchability was lessthan 25% in neem treatments and morethan 50% in the controls. Neem treat-ments also inhibited larval growth anddevelopment: 40 to 60% of 2nd-instarlarvae died in 14 days when confined toneem-treated banana pseudostems; thesurvivors were small in body size andweighed 4 to 6 times less than those inthe control. The higher the concentra-tion, the greater was the effect of neemmaterials.

Efficacy of neem materials againstC. sordidus and nematodes was evalu-ated under controlled pest infestationlevels in the drums at MPFS. Effectivemethods, frequency and rates of appli-cation of selected neem materialswere determined at MPFS and in farm-

ers’ fields, under different levels of soilfertility and pests infestation. In thosetrials, Nakyetengu (AAA-EA), a highlysusceptible cultivar to the above pestswas used.

Outdoors and fields experiments:in an outdoors experiment, NSP, NKPand NC were applied at 100 g/plant atplanting to pared or unpared bananasuckers planted in 100 or 200 L drum’scapacity and inoculated with 2000mixed nematodes and five pairs (fe-males and males) of the banana weevilper drum. A treatment with suckersdipped in NO-extract was also in-cluded. Compared with the control, 10months after treatments, neem materi-als significantly reduced the nematodepopulation and weevil damage on parwith Furadan applied at 40 g/plant. Inaddition, NSP-and NC-treated unparedsuckers supported much fewer nema-todes than pared treated suckers withthe same neem products, obviating theneed for paring of suckers. However,NKP and NO applications were toxic tothe banana plant.

Soil application of powdered NSP orNC was more effective than their ap-plication in aqueous forms. Applica-tion of NSP or NC at planting time andthen at 1, 2, 3, or 4-month intervals toplants grown under controlled pest in-festations in drums significantly re-duced nematode density and the wee-vil damage. Similarly, in the farmersÕfields, soil application of NSP or NC at60, 80 and 100 g/mat at planting andthen at 4-month interval significantly

Neem seed derivatives for themanagement of the bananaweevil, Cosmopolites sordidusGermar (Coleoptera:Curculionidae) and parasiticnematode complexPhD Thesis submitted to Kenyatta University, Nairobi, Kenya, July 1999.


reduced the weevil and nematodedamage, and increased yields by 27-50% over the control (first crop) andby 30-60% in the second crop. Furadanincreased the fruit yield by 27% overthe control in the first crop butdropped down to -2% in the secondcrop. Even under low soil fertility andhigh pest infestation levels, the neemtreatments controlled the pests andmarkedly increased the yield 7 to 10times more than that in the control.The application of NSP or NC at 200 to400 g/mat at 6-month intervals wastoxic to the banana plant.

Depending on the soil fertility anddoses of application, net gain over thecontrol obtained with application ofNSP or NC ranged from US$ 70 andUS$ 800 per hectare. However, a loss ofUS$ 700 per hectare was observed withthe Furadan application. Neem appli-cation at doses higher than 200 g/matwas uneconomical. The beneficial ef-fects of neem seed materials applica-tion on banana plant growth and de-velopment, pest control, andimplications of these findings in ba-nana pest management and furtherareas of investigation are discussed. �

Books, etc...

Evaluating bananas: a globalpartnership. Results of IMTPPhase IICompiled by G. OrjedaISBN: 2-910810-38-0

For the International Musa TestingProgramme (IMTP) Phase II,germplasm was evaluated for resis-tance to black Sigatoka (M. fijiensis),yellow Sigatoka (M. musicola) andFusarium wilt (Fusarium oxysporumf. sp. cubense). The majority of IMTPPhase II trials were planted during1996 and 1997. The first part of thispublication provides a synthesis offinal results (an overview of the finalreport and summary of results have al-ready been published in INFOMUSA

Vol. 8, No. 1, pp. 3-10). In the secondpart, full results are given for Sigatokasites in Cameroon, Colombia, CostaRica, Honduras, Nigeria, the Philip-pines, Tonga, and Uganda, and forFusarium wilt (Foc) sites in Australia,Brazil, Honduras, Indonesia, Malaysia,the Philippines, South Africa, Spain,Taiwan, and Uganda.

BananasISBN: 2-910810-37-2

This 16-page booklet, produced origi-nally in French for the 1998 Paris Agri-cultural Fair has now been translatedin English. It presents information onall the aspects of the crop: origin, di-versity, economic importance, role infood security, commercialization, pestsand diseases, research, processing.The brochure is available from INIBAPHeadquarters in Montpellier.

Announcements

IV international scientific seminarof plant protectionThe Convention Center of Varadero Beach,Matanzas, Cuba. June 11th -15th of 2001The Instituto de Investigaciones deSanidad Vegetal (INISAV) and the Cen-tro Nacional de Sanidad Agropecuaria(CENSA) organize, from the 11th to 5th

of June of the 2001, the IV InternationalScientific Seminar of Plant Protectionthat will take place in the Palace of Con-ventions at Varadero Beach.

In this forum, investigators, profes-sors, extensionists and officials of dif-ferent countries will discuss the prob-lems and more recent results, as wellas the tendencies of the plant protec-tion for the new millennium.

The scientific programme will in-clude plenary sessions, workshops, ofwhich one entitled Workshop on ba-nana pests and diseases: current situ-

ation and challenges for the new cen-tury, symposia and meetings, besidessessions of posters and commercial ex-hibitions.

To get more detailed informationplease contact the executive secre-taries of the Organizing Committee:Ileana Sandoval RamírezInstituto de Investigaciones deSanidad Vegetal. (INISAV)Calle 110 #514. between 5ta B and 5taF. Playa. C. P 11600. La Havana. CubaFax: (537) 240535 E-mail: [email protected] Díaz RodríguezCentro Nacional de SanidadAgropecuaria (CENSA) PO Box 10. San José de las Lajas, La Havana. CubaFax: (5364) 63897 E-mail: [email protected]

All those interested to get more in-formation on the «Workshop on ba-nana pests and diseases: current situa-tion and challenges for the newcentury» are invited to contact Dr LuisPérez Vicente, convener of the work-shop at the e-mail:[email protected] [email protected]

The International Foundation forScience - Call for research grantapplications from developingcountry scientistsThe International Foundation for Sci-ence (IFS) provides support to youngscientists of merit in developing coun-tries by awarding research grants andproviding grantees with additional ser-vices such as travel grants and pur-chasing assistance.

Research grants are awarded up to amaximum value of USD 12,000 for a pe-riod of one to three years and may be re-newed twice. They are intended for thepurchase of equipment, expendable sup-plies, and literature. Applicants must becitizens of, and carry out the researchin, a developing country. They shouldalso work at a university or national re-search institution in a developing coun-try (countries in Europe, includingTurkey and Cyprus, or the former SovietUnion do not qualify for support). Aswell as being under the age of 40 (under30 for applicants from China) and at thestart of their research career, candi-dates must possess a higher academicdegree, which should be at least an MScor equivalent.

The IFS supports projects dealingwith the management, use, and con-servation of biological resources. TheFoundation organizes its activities intosix Research Areas, viz Animal Produc-tion, Aquatic Resources, Crop Science,


Food Science, Forestry/Agroforestry,and Natural Products.

For further information and applica-tion forms in English and French writeto:IFS, Grev Turegatan 19, S-114 38Stockholm, SwedenFax: + 46-8-54581801Email: [email protected]://www.ifs.se

INIBAP News

First MUSALAC meetingOn June 6, 2000, in Cartagena de In-dias, Colombia, 14 national researchand development institutions repre-senting their respective countries (Bo-livia, Brazil, Colombia, Costa Rica,Cuba, Ecuador, Honduras, Jamaica,Mexico, Panama, Peru, Puerto Rico,Dominican Republic and Venezuela)and 4 regional/international institu-tions (CATIE, CIRAD, IICA and INI-BAP) signed, in the framework of FORAGRO, an Agreement for the Es-tablishment of the Plantain and Ba-nana Research and Development Net-work for Latin America and theCaribbean (MUSALAC).

The general objective of MUSALACis to increase the productivity andcompetitiveness of the plantain andbanana agribusiness through the en-hancement of scientific and technolog-ical activities; this involves strengthen-ing of national research anddevelopment systems, integration ofstakeholders, priority setting and coor-dination of actions in Latin Americaand the Caribbean.

MUSALAC’s specific objectives are:• To bring together conventional and

non-conventional genetic improve-

ment programmes and to urge themto focus on the rapid development ofimproved Musa varieties with abroad genetic base and consumeracceptability and to make theseavailable to farmers through na-tional research and developmentprogrammes.

• To develop and to extend participa-tory integrated management systemsaddressing priority problems using asustainable and profitable approach.

• To generate and to transfer agro-nomic and post-harvest managementtechnologies to increase the crop’sproductivity and sustainability.

• To favour farmer’s overall develop-ment by improving his/her competi-tiveness and to promote an increaseof the demand for Musa productsand by-products.

MUSALAC organizationMUSALAC is composed of:• a Steering Committee, comprising arepresentative of one institution ofeach member country, which will de-termine the Network’s policies, actionplans and projects in the medium andlong term. This Committee will meetonce a year. Dr Altagracia Rivera deCastillo, from CEDAF, Dominican Re-public was elected President of thisCommittee; Drs Rodrigo Aveldaño,from INIFAP, México, and AlvaroUribe, from CORPOICA, Colombia,were elected Vice-presidents.• an Executive Committee whose re-sponsibility will be to coordinate andfollow-up on MUSALAC’s general ac-tion plan and annual workplans. Dr Franklin E. Rosales, Coordinator ofINIBAP for Latin America and theCaribbean was appointed ExecutiveCoordinator.

• National Nodes, consisting mainlyof public and private national institu-tions whose mandate and responsibili-ties include plantain and banana re-search and development at thenational level, as well as coordinationmechanisms (for example nationalnetworks, support groups, etc.).

MUSALAC will stimulate the partici-pation of international or regionaltechnical and financial cooperation or-ganizations related to plantain and ba-nana research and development,whose mandates coincide with theNetwork’s objectives.

In the first stage, priority will begiven to four thematic components:• Genetic improvement• Integrated pest management• Crop management• Socioeconomic development.

After signing the Agreement, partici-pants split into four thematic groupsto elaborate, with the help of Dr JorgeSaravia from CIAT, a logical frameworkfor four subjects identified as regionalpriorities, defined in order to developprojects for MUSALAC.

The event was inaugurated by DrJuan Lucas Restrepo, Director of theAgrarian Development Office ofColombia’s National Planning Depart-ment. Lectures were given by Drs En-rique Alarcon from IICA, Costa Rica,Miguel Gomez Lim from CINVESTAV,Mexico and Carlos Quiros from CIAT,Colombia, focusing on: “Latin Americaand the Caribbean agricultural scenar-ios addressed from a technological per-spective”; “Plant biotechnology in LatinAmerica: opportunities and challenges”;and “Participatory research”, respec-tively. Two presentations were also madeby IPGRI-INIBAP staff members onPROMUSA and IMTP (Jean-Vincent

The participants of the first MUSALAC meeting.

Escalant) and on the global INIBAP in-formation system (Claudine Picq).

New staff at INIBAPINIBAP has recently recruited six new

staff members.Guy Blomme, a Belgian citizen, is an

Agricultural Scientist with a specialisa-tion in crop husbandry and tropical agri-culture. He completed two years of post-graduate studies in Tropical Agricultureat the Ecole supérieure d’agronomietropicale in Montpellier. He has just suc-cessfully defended his PhD at KUL, Leu-ven, Belgium. The title of the thesis was“The interdependence of root and shootdevelopment in banana (Musa spp.)under field conditions and the influenceof different biophysical factors on thisrelationship”. The research was carriedout at the IITA Onne High Rainfall sta-tion where Guy spent almost five years,and was supervised by Prof. R. Swennenand Dr A. Tenkouano from IITA. Guytook up his new position of AssociateScientist, Musa Technology Transfer, atthe INIBAP Regional Office for Easternand Southern Africa, Kampala, Ugandaat the beginning of February 2000.

Max Ruas, a French citizen, has aMasters’ Degree in Biology (Maîtrisede biologie des organismes et des pop-ulations) and a post-Masters’ Degreein Computers Sciences (Informatiqueappliquée aux organisations), bothfrom the University of Montpellier.Max has previous professional experi-ence as a Data Manager in Biology andas a Computer Programmer. Max tookup his new position of Computer Ser-vices Assistant at the INIBAP office inMontpellier on 28 February 2000.

Deborah Karamura, a Ugandan citi-zen, has been working for the NationalAgricultural Research Organisation(NARO) Uganda, as a banana taxono-mist and a germplasm specialist sinceJanuary 1994. She holds a Doctorate incrop taxonomy, a Masters degree inPure and Applied Taxonomy (Univer-sity of Reading) and a Bachelor of Sci-ence degree in Botany and Zoology(Makerere University). Deborah hasrecently been recruited by INIBAP asa Musa Germplasm Specialist for theMusa in situ Conservation Projectwhich is being implemented in Ugandaand Tanzania, and she is based at INIBAP’s Regional Office in Kampala.Deborah will be responsible for variousaspects of the project, including docu-menting cultivar diversity in the regionand supporting and training NARS personnel in methodologies forgermplasm characterization. Deborahwill also commit 30% of her time toNARO germplasm research activities.In the project, Deborah will workclosely with staff from the Uganda andTanzania NARS, IITA, ICIPE and anumber of NGOs.

Charlotte Lusty, a British citizen,has a BSc Honours Degree in Biologi-cal Sciences (Zoology) from EdinburghUniversity (1988-1991). After graduat-ing from University, Charlotte spentover two years working on variousfield-based projects in the UK, Kenyaand Tanzania. Since 1994, she hasbeen working for the World Conserva-tion Monitoring Centre (WCMC), de-voted mainly to the management of in-formation resources in the plantsprogramme. She acquired wide experi-

ence in species data management, liai-son within a global network of experts,workshop organisation and productionof materials and publications. Char-lotte took up her new position of Im-pact Assessment and Public Aware-ness Specialist at the INIBAP office inMontpellier as of 5 June 2000. Char-lotte’s duties at INIBAP will include:the evaluation and synthesis of scien-tific data and information, preparationof public awareness materials for theINIBAP programme and assistance tothe INIBAP Regional Coordinators inthe area of public awareness/impactassessment, as well as assistance withthe production of INIBAP publications.

Luis Pocasangre, a Honduran citi-zen, graduated from the Tropical Agri-culture Research & Higher EducationCentre, Turrialba, Costa Rica in 1992(MSc in Plant breeding, emphasis onbiotechnology) and from the Universi-dad Nacional Autónoma de Honduras(BS Agronomy) in 1988. Over the last10 years, Luis has acquired wide expe-rience in various laboratories: pathol-ogy, nematology, tissue culture,biotechnology, plant physiology andgermplasm conversation laboratories.Since 1996, he has worked as a Re-search Assistant at the UniversitätBonn, where he was responsible forthe biological enhancement of tissueculture plantlets for banana produc-tion systems. Luis will be defendinghis PhD thesis in plant pathology/ne-matology at the Institut fürPflanzenkrankheiten, UniversitätBonn in June 2000, and will be takingup his new position of Associate Scien-tist, Technology Transfer, as of 1 July2000. Luis will be assisting the INIBAPRegional Coordinator for Latin Amer-ica and the Caribbean.

Charles Eledu, a Ugandan citizen,has an MSc in Soil Surveying from theInternational Institute for AerospaceSurveys and Earth Sciences, the Nether-lands, and a BSc (Hons) in Agriculturefrom the University of Makerere,Uganda. For the past three years he hasbeen working as a GIS Research Associ-ate at the International Centre for Trop-ical Agriculture (CIAT), in Uganda,where he was responsible for developingand implementing a bean database for


Franklin Rosales, INIBAP regional coordinator, signs the MUSALAC Agreement.

Luis Pocasangre Charles EleduCharlotte LustyGuy Blomme Max Ruas Deborah Karamura


Africa. He has also provided GIS supportfor the IITA banana programme inUganda. Charles has recently been re-cruited as GIS Expert for the bananabaseline information project being im-plemented in Eastern and SouthernAfrica by INIBAP.

Departure of Gisella OrjedaGisella Orjeda joined INIBAP inMay 1996 as Musa Germplasm Improve-ment Scientist. Gisella, a Peruvian na-tional, took over responsibility for thesecond Phase of the International MusaTesting Programme and, during hertime with INIBAP, was also actively in-volved in the initiation of the GlobalProgramme for Musa Improvement,PROMUSA. Gisella travelled extensivelyin relation to her work on the IMTP, vis-iting the evaluation sites around theworld and working with participatingprogrammes in the collection and analy-sis of evaluation data. One of Gisella’smajor achievements during her timewith INIBAP was the development ofthe IMTP database, which now containsinformation on over 30 candidate clonesavailable for evaluation in future IMTPtrials. Gisella always put great emphasison ensuring the statistical validity ofdata generated by IMTP trials andworked hard on developing standard for-mats for data collection to allow easycomparison of data collected from dif-ferent sites. On completion of the PhaseII trials, Gisella performed a full statisti-cal analysis of results from 17 sites andensured the publication of the final re-port of IMTP II, which is now availablefrom INIBAP.

After three years of working as a re-search coordinator with INIBAP,Gisella decided that she wished to re-turn to hands-on research. Accord-ingly, her last six months with INIBAPwere spent working in collaborationwith CIRAD on the molecular charac-terisation of banana cells derived fromprotoplast fusion experiments. Oncompletion of this short research pro-ject, Gisella left INIBAP in order topursue her research career.

The staff of INIBAP would like totake this opportunity to wish Gisellaall the very best for the future.

I5th anniversaryThis year INIBAP is celebrating its 15th

Anniversary. In recognition of this an-niversary, a number of special activitiesand initiatives are being undertaken byINIBAP. These include the translation ofthe beautiful ‘Bananas’ brochure fromFrench into English and the productionof a series of factsheets dealing with ba-nanas as a global food crop and INIBAP’srole in Musa research and development.

The anniversary will be formallymarked at the next global PROMUSAmeeting, due to take place in Thailand inNovember. This meeting will coincidewith a national banana symposium andexhibition.

In looking back over the last 15 years,it can be seen that in this short period,INIBAP has seen remarkable growth andevolution. It has developed from a smallindependent institute with less than 10staff, to becoming a significant pro-gramme of the CGIAR, with over 40 staffmembers who are today located in sevencountries around the world. At the pre-sent time, INIBAP is actively supportingmore than 40 banana research projectswhich are being carried out in 30 coun-tries world-wide, while more than 50countries are members of regional net-works coordinated by INIBAP.

External Review of INIBAPDuring February and March 2000, theINIBAP programme was reviewed by anexternal panel of experts commissionedby IPGRI. The review panel consisted ofDr Claude Fauquet (Director, ILTAB,USA), Prof. Joseph Mukibi (Director-General, NARO, Uganda), Dr Michel deNucé de Lamothe (President Agropolis,France) and Prof. Dolores Ramirez(University of the Philippines, PanelLeader).

The panel members each visited anINIBAP regional office and two orthree of the NARS in the different re-gions. The team also visited the INI-BAP genebank in Belgium and INIBAPHeadquarters in Montpellier.

The review panel reported veryfavourably on the INIBAP programme,both in terms of the regional andglobal activities being undertaken.Particular strengths were noted in theareas of germplasm exchange,germplasm improvement, documenta-tion and training. The review panelalso commended INIBAP for its way ofoperating and noted that networkingand outsourcing allows an impressiveamount of work to be conducted by asmall team.

Several areas for increased activityin the future were identified, includingthe need for a conservation strategyfor a more complete coverage of thewhole Musa genepool, and greater useof Musa diversity in breeding and im-provement activities. INIBAP is al-ready taking steps to address theseand other issues raised by the reviewteam.

Finally, the review panel noted that,compared to the global importance ofthe crop, banana research is limited,and this is mainly due to the low levelof funds devoted to such research.

However, it was recognised that ba-nana research needs at the interna-tional level are best addressed througha networking approach and the panelbelieved that the structure developedby INIBAP is well adapted to meet fu-ture needs. Furthermore, the panelrecommended that IPGRI brings to theCGIAR’s attention the INIBAP modelas a scheme for addressing concerns ofother commodities or systems.

EXPO 2000EXPO 2000, which takes place inHannover, Germany from 1 June to 31October has taken as its key theme«Humankind - Nature – Technology -A whole new world». One of theunique features of EXPO 2000 is thatit does not take place in Hannoveralone. EXPO 2000 is considered toexist wherever people develop andrealise ideas for the future. One ofthe ways EXPO 2000 is aiming to be-come a World Exposition in the truesense of the word is through a com-pletely new concept entitled “Pro-jects around the World”. INIBAP’sgenebank has been selected by EXPO2000 as one of these ‘Projects aroundthe world’.

By participating in EXPO 2000, INI-BAP is hoping to raise the profile ofbananas as a staple food crop. INI-BAP will emphasise the fact thatmore than 85% of the world-wide ba-nana harvest of 88 million tonnes isproduced by small-scale farmers, al-most exclusively for local consump-tion. Bananas are essentially a staplefood crop, and this is a fact that INI-BAP will be promoting at EXPO 2000.

INIBAP Web siteAs reported in the last issue of INFO-MUSA (Vol. 8,2), INIBAP has recentlylaunched a new Web site which pro-vides a wide range of informationabout INIBAP as well as on-line accessto INIBAP’s databases and selectedpublications. We are pleased to an-nounce that the Web site is now avail-able in three languages, English,French and Spanish.

Recent additions to the site in-clude the English and Spanish ver-sions of the report of the Interna-tional Workshop on the “Productionand Marketing of Organic Bananas bySmallholder Farmers”, which washeld in the Dominican Republic inNovember 1999, and informationabout the upcoming InternationalSymposium on the Molecular andCellular Biology of Bananas and thenext global PROMUSA meeting.The Web site address is: http://www.inibap.org

43 INFOMUSA — Vol 9, N°1

INIBAP addresses• Headquarters:Parc Scientifique Agropolis II34397 Montpellier Cedex 5FRANCEe-mail: [email protected]://www.inibap.org

DirectorDr Emile FRISONe-mail: [email protected]

Plant Genetic Resources ScientistDr Jean-Vincent ESCALANTe-mail: [email protected]

Germplasm Conservation ScientistMs Suzanne SHARROCKe-mail: [email protected]

Head Information/CommunicationsMs Claudine PICQe-mail: [email protected]

Officer in charge MGISMs Elizabeth ARNAUDe-mail: [email protected]

Financial ManagerMr Thomas THORNTONe-mail: [email protected]

• Regional Office for Latin America andthe Caribbean

Regional CoordinatorDr Franklin E. ROSALESAssociate Scientist, Musa technology transferLuis POCASANGREC/o CATIEApdo 60-7170 Turrialba, COSTA RICATel/Fax: (506) 556 2431e-mail: [email protected]• Regional Office for Asia and the Pacific

Regional CoordinatorDr Agustín MOLINAC/o Collaborator Center IRRICollege, Laguna 4031PHILIPPINESFax: (63 49) 536 05 32e-mail: [email protected]

• Regional Office for West and CentralAfricaRegional CoordinatorDr Ekow AKYEAMPONGAssociate expert entomology: Stjin MESSIAENC/o CRBP - BP 12438Douala, CAMEROONFax: (+237) 42 91 56E-mail: [email protected]

• Regional Office for Eastern and Southern AfricaRegional CoordinatorDr Eldad KARAMURAAssociate Scientist, Technology transferGuy BLOMMEPo Box 24384Kampala, UGANDAFax: (+256-41) 28 69 49e-mail: [email protected]• INIBAP Transit Center (ITC)Officer in chargeMs Ines VAN DEN HOUWEKatholieke Universiteit LeuvenLaboratory of Tropical Crop ImprovementKardinaal Mercierlan 92B-3001 Heverlee – BELGIUMFax: (32 16) 32 19 93e-mail: [email protected]

• Associate Experts, NematologyMs Inge VAN DEN BERGHC/o VASIVan Diem, Than TriHanoi, VIETNAMFax: (84) 4 861 39 37e-mail: [email protected] Thomas MOENSC/o CORBANALa Rita Research StationApdo 390-7210Guápiles, COSTA RICAFax: (506) 763 30 55e-mail: [email protected]

Typescripts should be prepared in Eng-lish, French or Spanish and submitted induplicate to the Managing Editor. Theyshould be double-spaced throughout. Allpages (including tables figures, legendsand references) should be numberedconsecutively. Include the full name ofall the authors of the paper, togetherwith the addresses of the authors at thetime of the work reported in the paper.Indicate also the author nominated toreceive correspondence regarding thepaper.

If the typescript was prepared on acomputer, please send a copy on diskette(or by e-mail) along with the printedones, indicating the name and version ofthe wordprocessor used.• Abstracts: An abstract not exceeding

200-250 words should be sent in thesame language as the typescript, aswell as translations (including thetitle) into the two other languages, ifthis is possible.

• Acronyms: These should be written infull the first time they appear in thetext, followed by the acronym in pa-renthesis.

• References: All literature referencesmade in the text should be referred toby author(s) and year of publication(e.g.: Sarah et al. 1992, Rowe 1995). Alist of references, in alphabeticalorder, should be provided at the end ofthe text.

Please follow the style shown below:Periodicals: Sarah J.L., C. Blavignac &M. Boisseau. 1992. Une méthode de la-boratoire pour le criblage variétal desbananiers vis-à-vis de la résistance auxnématodes. Fruits 47(5): 559-564.Books: Stover R.H. & N.W. Simmonds.1987. Bananas (3rd edition). Longman,London, United Kingdom.Articles (or chapters) in books: BakryF. & J.P. Horry. 1994. Musa breeding atCIRAD-FLHOR. Pp. 169-175 in The Im-provement and Testing of Musa: a Glo-bal Partnership (D.R. Jones, ed.). IN-IBAP, Montpellier, France.Tables: These should be numbered

consecutively and referred to by thesenumber in the text. Each table shouldinclude a title.

Illustrations: These should be num-bered consecutively and referred to by

these numbers in the text. Each illustra-tion should include a clear and simplecaption.

Graphs: provide the correspondingraw data with the graphs.Drawings: provide originals if this ispossible.Black and white photographs: providethem on bright paper and with goodcontrast.Colour photographs: provide goodquality proofs and films or originalslides.

Note: When plant material used for theexperiments reported originates or isregistered in the INIBAP genebank, itsaccession number (ITC code) should beindicated within the text or in a tabularform.

Thank you in advance for followingthese instructions

This will facilitate and acceleratethe editing work.

Instructions to authors

The following publications are available from headquarters:

CIRAD/INIBAP 2000. Bananas.

INIBAP. 2000. G. Orjeda (compil.). Evaluating bananas: a global partnership.Results of IMTP Phase II.

INIBAP/EARTH/IDRC. 1999. F.E. Rosales, S.C. Tripon & J. Cerna (eds).Organic/environmentally friendly banana production. Proceedings of aworkshop held at EARTH, Guácimo, Costa Rica, 27-29 July 1998 (in press).

INIBAP/CRBP/CTA/CF. 1999. C. Picq, E. Fouré & E.A. Frison (eds). Bananas andfood security/Les productions bananières: un enjeu économique majeur pour lasécurité alimentaire. Proceedings of an International Symposium held inDouala, Cameroon, 10-14 November 1998.

INIBAP/FHIA. 1999. F.E. Rosales, E. Arnaud & J. Coto (eds). A tribute to the workof Paul H. Allen: a catalogue of wild and cultivated bananas.

INIBAP/RF/SDC. 1999. E.A. Frison, C.S. Gold, E.B. Karamura & R.A. Sikora (eds).Mobilizing IPM for sustainable banana production in Africa. Proceedings of aworkshop on banana IPM held in Nelspruit, South Africa, 23-28 November 1998.

INIBAP 1999. E. Akyeampong (ed.). Musa Network for West and Central Africa.Report of the second Steering Committee meeting held at Douala, Cameroon,15-16 November 1998.

INIBAP 1999. Annual Report 1998.

INIBAP 1999. K. Shepherd. Cytogenetics of the genus Musa.

INIBAP 1998. E. Akyeampong (ed.). Musa Network for West and Central Africa.Report of the first Steering Committee meeting held at Douala, Cameroon, 8-10 December 1997.

INIBAP 1998. E.A. Frison & S.L. Sharrock (eds). Banana streak virus: a uniquevirus-Musa interaction? Proceedings of a workshop of the PROMUSA virologyworking group held in Montpellier, France, 19-21 January 1998.

INIBAP 1998. C. Picq (ed.). Segundo seminario/taller de la Red regional deinformación sobre banano y plátano de America Latina y el Caribe. San José,Costa Rica, 10-11 July 1997.

INIBAP 1998. B.K. Dadzie. Post-harvest characteristics of black Sigatoka resistantbanana, cooking banana and plants hybrids. INIBAP Technical Guidelines 4.

INIBAP 1998. G. Orjeda in collaboration with the PROMUSA working groups onSigatoka and Fusarium. Evaluation of Musa germplasm for resistance toSigatoka diseases and Fusarium wilt. INIBAP Technical Guidelines 3.

INIBAP/ACIAR 1997. E. Arnaud & J.P. Horry (eds). Musalogue, a catalogue ofMusa germplasm: Papua New Guinea collecting missions 1988-1989.

INIBAP/CTA/FHIA/NRI/ODA 1997. B.K. Dadzie & J.E. Orchard. Post-harvestRoutine Screening of Banana and Plantain Hybrids: Criteria and Methods.INIBAP Technical Guidelines 2.

INIBAP/CTA 1997. P.R. Speijer & D. De Waele. Screening of Musa Germplasm forResistance and Tolerance to Nematodes. INIBAP Technical Guidelines 1.

INIBAP/The World Bank 1997. E.A. Frison, G. Orjeda & S. Sharrock (eds).PROMUSA: A Global Programme for Musa Improvement. Proceedings of ameeting held in Gosier, Guadeloupe, March 5 and 9, 1997.

INIBAP-IPGRI/CIRAD. 1996. Descriptors for Banana (Musa spp.).

The following publications are available from Asia and the Pacific office:

INIBAP. 2000. R.V. Valmayor, S.H. Jamaluddin, B. Silayoi, S. Kusumo, L.D. Danh,O.C. Pascua & R.R.C. Espino. Banana cultivar names and synonyms inSoutheast Asia.

INIBAP/ASPNET 1999. V.N. Roa & A.B. Molina (eds). Minutes: Eighth meetingof INIBAP/ASPNET Regional Advisory Committee (RAC) hosted bythe Queensland Horticulture Institute (DPI) in Brisbane, Australia, 21-23 October 1998.

INIBAP/ASPNET 1998. Minutes: Seventh meeting of INIBAP/ASPNET RegionalAdvisory Committee (RAC) hosted by the Vietnam Agricultural ScienceInstitute (VASI) in Hanoi, Vietnam, 21-23 October 1997.

INIBAP/ASPNET 1997. V. N. Roa & R. V. Valmayor (eds). Minutes: Sixth meetingof INIBAP/ASPNET Regional Advisory Committee (RAC) hosted by National Research Center on Banana (ICAR) in Tiruchirapalli, India, 26-28 September 1996.

INIBAP/ASPNET 1996. R. V. Valmayor, V. N. Roa & V. F. Cabangbang (eds).Regional Information System for Banana and Plantain - Asia and the Pacific(RISBAP): Proceedings of a consultation/workshop held at Los Baños,Philippines, 1-3 April 1996. (ASPNET Book Series No. 6).

Publications from INIBAP

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PROMUSA IINFOMUSA — Vol 9, N° 1

PROMUSA N° 5

Contents

3rd global meeting of PROMUSA,Bangkok, Thailand, 06-08 November,2000 . . . . . . . . . . . . . . . . . . . . . . . . . .p. I

2nd international symposium on themolecular and cellular biology of ba-nana, Byron Bay, Australia, 29 Octo-ber-3 November 2000 . . . . . . . . .p. II

Banana Genomics Initiative . . . . .p. II

What is PROMUSA?

The Global Programme for Musa

Improvement (PROMUSA) is a broad based

programme which aims at involving all the

major players in Musa improvement. It was

developed as a means to link the work

carried out towards addressing the problems

of export banana producers, with those

initiatives directed towards improving banana

and plantain production at the subsistence

and smallholder level. The global programme

builds upon existing achievements and is

based upon ongoing research initiatives.

PROMUSA is therefore a mechanism to

further maximize the outputs and accelerate

the impact of the overall Musa improvement

effort. The programme is an innovative

mechanism to bring together research carried

out both within and outside the CGIAR,

creating new partnerships between National

Agricultural Research Systems (NARS) and

research institutes in both developing and

developed countries. The formation of such

partnerships will also contribute to

strengthening the capacity of NARS to

conduct Musa-related research.

The major thrust of PROMUSA is to develop

a wide range of improved banana varieties

from which growers worldwide can select

those most suited to their needs. The

programme brings together conventional

breeding based on hybridization techniques

with genetic engineering and

biotechnological breeding approaches. This

broad-based genetic improvement effort is

supported by research being carried out on

specific pests and diseases within the

various PROMUSA working groups. An

efficient mechanism for evaluating new

varieties produced within the framework of

PROMUSA is also an essential component of

the programme.

PROMUSAA global Programme for Musa Improvement

The second global meeting of PRO-MUSA was held in Douala,Cameroon, in November 1998. Themeeting was attended by 70 re-searchers and consisted of a plenarysession, followed by individual work-ing group meetings. The report of thismeeting was published in the PRO-MUSA section of INFOMUSA Vol 7,No. 2.

The third global meeting shouldallow a fur ther step forward to bemade in the improvement of bananaand plantain production at the subsis-tence and smallholder level.

Programme

Monday 06 November, 2000:Inauguration of the meetingIntroductionPlenary sessionReport of the chairpersons of theworking groups:• Genetic improvement working

group,• Sigatoka working group,• Nematology working group,• Fusarium working group,• Virology working group.

Introduction to the different work-shops

Tuesday 07 November, 2000Steering Committee meetingWorkshops

• “Towards a strategy for thedevelopment of new hybridsresistant to nematodes” whichincludes both classical breeding andbiotechnology.

• “BSV in germplasm improvementand exchange”

Wednesday 08 November 2000:Plenary sessionReports from the different workshopsReport from the Steering CommitteeAspect of the functioning of PRO-MUSAVisit to Banana exposition (tentative)

Thursday 09 November 2000Departure of participants

ParticipationParticipation in the meeting is limitedto PROMUSA participants only. Non-participants in PROMUSA who havean interest in attending the meetingare invited to contact the MeetingSecretariat at the address below:

Meeting SecretariatJean-Vincent Escalant INIBAP Parc Scientifique Agropolis II 34397 Montpellier, France Tel: + 33 4 67 61 13 02 Fax: + 33 4 67 61 03 34 e-mail: [email protected]://www.inibap.org/promusameeting/promusameeting.htm

3rd global meeting of PROMUSA, Bangkok, Thailand,06-08 November, 2000

II PROMUSA INFOMUSA — Vol 9, N° 1

2nd Internationalsymposium on themolecular and cellularbiology of banana,Byron Bay, Australia,29 October-3November 2000

First annoucementThe inaugural Symposium on the Mol-ecular and Cellular Biology of Bananawas held in March 1999 in Ithaca, NewYork and was a great success drawingparticipants from diverse backgroundsreflecting the extent to which molecularbiology can be utilised in modern agri-culture.

The programme includes: Wel-come reception, presentation oforal papers and posters sessions,tour of banana field trials, confer-ence dinner

The themes covered by the sympo-sium will be:• Genomics,• Gene expression in transgenic

plants,• Plant pathology and disease

resistance,• Biodiversity and evolution,• Biochemistry and fruit ripening,• Intellectual property and genetically

modified organisms.To receive the registration booklet,please contact: Ms Di O’Rourke, Banana sympo-sium, Faculty of science, QueenslandUniversity of Technology, GPO Box2434, Brisbane, Qld, 4001, Australia,Fax: 61 7 3864 5100You could also visit the web site:http://www.inibap.org/byronbay/Byronbay. html

PublicationsIn the framework of the Nematologyworking group of PROMUSA, researchon nematode resistance screening hasbeen carried out and three papers will bepublished as PROMUSA research.

1) Host plant response of banana(Musa spp.) cultivars from SoutheastAsia to nematodes by R. Stoffelen, VuThi Thanh Tam, R. L. Swennen and D.De Waele, International Journal of Nema-tology 9(2): 130-136.

Abstract. Thirteen Musa genotypescommonly grown in Malaysia and Viet-nam were evaluated for their resistance toRadopholus similis, Pratylenchus coffeaeand Meloidogyne spp. The nematode -host plant response was compared withthe susceptible cultivars ‘Grande Naine’and ‘Cavendish 901’. In vitro propagatedplantlets were potted in loamy sand in thegreenhouse and inoculated with approxi-mately 1000 lesion-nematodes or 2500-5000 root-knot juveniles at 4 weeks afterplanting. Reproduction of the nematodeswas determined at 8 or 10 weeks after in-oculation depending of the species. AllMalayasian and Vietnamese cultivarsscreened were at least as susceptible toR. similis, P. coffeae and Meloidogynespp. as the susceptible reference culti-vars. Differences in susceptibility betweencultivars were observed.

2) Host plant response of Fusariumwilt resistant Musa genotypes toRadopholus similis and Pratylenchuscofffeae by R. Stoffelen, R. Verlinden, J.Pinochet, R. L. Swennen and D. DeWaele. International Journal of Pest Man-agement (accepted).

Abstract. Ten Musa genotypes whichwere accepted by the International MusaTesting Programme (IMTP) to be resis-tant or moderately resistant to Fusariumwilt caused by Fusarium oxysporum f. sp.cubense and three Fusarium wilt suscep-tible cultivars were evaluated for their re-sistance to Radopholus similis and Praty-lenchus coffeae and their nematode -host plant response compared with thesusceptible cultivar ‘Grande Naine’. Invitro propagated plantlets were trans-ferred to the greenhouse in loamy sand inpots and inoculated with approximately1000 nematodes at 4 weeks after plant-ing. Reproduction of R. similis and P.coffeae in the roots was determined at re-spectively 8 and 10 weeks after inocula-tion. The ‘Pisang Jari Buaya’ accessionsITC0312 and ITC0690, and ‘Yangambikm5’ were resistant to R. similis. ‘PisangLilin’, ‘Bluggoe’, ‘Saba’, ‘Gros Michel’,‘Williams’, ‘GCTCV 215’, ‘GCTCV 119’,

‘FHIA-01’, ‘PA 03.22’, ‘PA 03.44’ were assusceptible to R. similis as ‘GrandeNaine’. None of the 14 genotypes evalu-ated were resistant to P. coffeae.

3) In-Field behaviour of bananaplants (Musa AA sp.) obtained after re-generation of cryopreserved embryo-genic cell suspensions by F.X. Côte, O.Goue, R. Domergue, B. Panis and C.Jenny. CryoLetters 21: 19-24

Abstract. This study describes the in-field behaviour of bananas (Musa AA sp.)obtained after regeneration of cryopre-served embryogenic cell suspensions.Observations were focused on the classi-cal vegetal development descriptors. Weobserved no significant differences be-tween the cryopreserved-derived plantsand the control plants with respect to theplant height and circumference, the num-ber of leaves, the number of fruits, thefruit length, the fruit diameter and weight,the bunch weight and the date of harvest.During the first culture cycle, 2 out of 11descriptors analysed were however foundto be different between the control andthe cryopreserved suspensions derivedplants. These were the numbers of nodalclusters of the inflorescence (usuallycalled ‘hands’) and the date of flowering.These differences were, however, quiteminor as the two cases togetheramounted to only 2% of the control value.During the second cycle of culture, nosignificant difference between the twogroups of plants was found whatever theparameter analysed. These results sug-gest that, with the experimental condi-tions of the study, there is no difference atthe agronomic level between plants pro-duced from cryopreserved embryogeniccell suspensions and control plants.

Banana genomicsinitiativeReport of a meeting held on 6-8 April 2000 in MontpellierFrance, within the framework of PROMUSA

IntroductionModern crop improvement is basedon molecular marker assisted selec-tion and introgression of agronomictraits of interest, such as pest resis-

INFOMUSA — Vol 9, N° 1 PROMUSA III

tance or quality. Various ongoing re-search projects have allowed geneticmaps to be constructed, genes to becloned, expression assays to be per-formed, promotors to be tested andgene constructs to be transferred intocultivars.

Though still in its infancy, the re-sults of functional genomics of modelplants will increase the understand-ing of basic plant biology as well asthe exploitation of genomic informa-tion for crop improvement. For theidentification of gene functions of awhole organism, functional genomicstechnology now focuses on highthroughput (HTP) methods:• Insertion mutant isolation,• Gene chips or microarrays,• Proteomics.

All these and many more HTPtechniques in gene function analysisoffer new uses for genes that are dis-covered by sequencing.

The creation of tools to study thegenome, the transcriptome itself, willmake a major contribution towardsrapid progress in Musa improvement.BAC, EST and cDNA l ibrar ies,micro/macro arrays and DNA-chipsas well as maps (genetic, cytogeneticand physical) and expression chartswill foster the development of Musagenomics in the same way that mole-cular markers profited from the re-finement of Musa genetics.

Plant genomics is a newly emerg-ing field that holds the promise of de-scribing an entire genetic repertoireof plants. The information derivedfrom studies of plant genomics willhelp us understand how genes en-able a plant to carry out its functionsas a living organism, and how the di-versity of functions in all plants arerelated to simple changes in individ-ual genomes. Plant genomics ulti-mately may be used to geneticallymodify plants for optimal perfor-mance in different biological, ecologi-cal and cultural environments for thebenefit of humans and the environ-ment.

In order to make rapid progress ingenomics research as applied toMusa, a meeting was organized inthe framework of PROMUSA, bring-

ing together the main researchteams working in this area.

Toward the end of the meeting aremarkable degree of consensus forthe Banana Genomics initiative wasreached. All the parties agreed toform a Banana Genomic consortium.PROMUSA therefore provides astrong opportunity for this consortiumto become a leader in banana ge-nomics research through the devel-opment and implementation of a vi-sionary strategy that cuts acrossdifferent institutions around theworld.

How the consortium will takeadvantage of existingstrengthsDeciphering the banana genome isan enormous task that will requireparticipation and collaboration of sci-entists around the world. The Ba-nana Genomics Consor tium wil lbring together and enhance com-bined expertise (from both the publicand private sector).

The development of a banana ge-nomics strategy and inter-institutionaland inter-disciplinary interaction inthe design of experiments, the inter-pretation of data, and the formulationof project proposals will greatly en-hance the global efforts in this areaof genomics.

The Global Programme for MusaImprovement (PROMUSA) offers agood framework to assume world-wide leadership in the new initiativeon banana genomics, whose activi-ties will be developed within the Ba-nana Genomics Consortium. PRO-MUSA is a broad-based programmethat aims at involving all the majorplayers in Musa improvement. Themajor thrust of PROMUSA is to de-velop a wide range of improvedMusa varieties, bringing togetherconventional breeding and biotech-nology supported by research that iscarried out on pests and diseaseswithin the various working groups.

ObjectivesTo assure the sustainability of the ba-nana as a staple food crop for a largepart of the world’s population and itsever-changing food needs, and pro-gressively restrictive environments.This can be achieved through an inte-grated genetic and genomic under-standing which can allow targetedbreeding and transgenic strategies.

To use post genomics technologiesto better tap the bio-diversity in orderto improve local bananas for the bene-fit of the smallholder farmer.

Modus operandiThe consortium will operate under theguidance of a scientific committeewithin PROMUSA.

Criteria for membership to the con-sortium will be based on:• High level of expertise (scientific

publications),• Facilities,• Commitment to abide by the rules of

the consortium.This will be elected through an open

consultation within the Scientific Com-mittee with a 2/3 majority.

Composition and role of theScientific CommitteeDr Françoise Carreel, CIRAD-FLHOR,Montpellier, FranceProf. James Dale, QUT, Brisbane,AustraliaDr. Jaroslav Dolezel, IEB, Olomouc,Czech RepublicProf. Peter Gresshoff, QueenslandUniversity, Brisbane, AustraliaDr. Pat Heslop-Harrison, John InnesCenter, Colney, United KingdomDr. Dieter Kaemmer, University ofFrankfurt, Frankfurt, GermanyDr. Pierre Lagoda, CIRAD-BIOTROP,Montpellier, FranceDr. Michael Pillay, IITA, NigeriaDr. Lazlo Sagi, KUL, Leuven, Belgium.

Each member of the committee willbe responsible for arranging a tempo-rary or permanent replacement fromthe represented group when appropri-ate. New members will be invited tojoin the Scientific Committee based ona nomination from one member of thecommittee and an affirmative vote by

IV PROMUSA INFOMUSA — Vol 9, N° 1

a majority. It is anticipated that thecommittee will maintain regular com-munication and will meet annually,taking advantage of PROMUSA facili-ties whenever possible.

It was agreed upon that the role ofthe Scientific Committee is to providean oversight and direction to the con-sortium. This committee will also beresponsible for the setting up of theprogramme priorities, based on anopen discussion with the group.

Rules of the consortiumPeople participating in the consortium(members) shall agree:• To share within the group all the in-

formation obtained from a projectfunded through the consortium. In-formation will be freely available toall the members.

• The consortium will negotiate ac-cess to enabling technologies withthe private sector.

• To share materials which are rele-vant to the development of enablingtechnologies.

• To facilitate access to infrastructurewithin the consortium.(Materials: these include clones, li-braries, and sequence informationas well as protocols, methods andpreprints, plant material, tissue sam-ples, DNA probes. Co-authorshipsshould be pre-arranged to securejoint ownership of technology.)

How genomics can benefit theimprovement of bananaSeveral research institutions, universi-ties, and private companies are nowinvolved in the improvement of bothdessert and cooking bananas by con-ventional breeding and, increasingly,by genetic engineering. The classicalbreeding strategy involves crossing afertile diploid accession onto good edi-ble triploid cultivars in order to createtetraploid hybrids. Another strategyaims at “reconstructing” triploid culti-vars by crossing improved diploidsonto artificially doubled-diploids (au-totetraploids).

This breeding effort could be con-siderably strengthened and acceler-ated by a better knowledge of thegenome at molecular and chromoso-mal levels.

A very important problem for breed-ing and genetic analysis is the vari-ability of chromosome structure be-tween different accessions due tostructural rearrangements. Transloca-tions and inversions of segments ofchromosomes lead to important meio-sis irregularities and irregular chromo-some transmission. Genes usuallysegregating independently will showin that case variable degrees of link-age in the progenies of structural hy-brids. The overall effect of this struc-tural hybridity interferes with thebreeders’ efforts at recombining andtransferring desirable traits from wildand cultivated diploids to new im-proved hybrids.

It is highly necessary to developnew molecular tools that will allow thelocation of important genes for traitssuch as pest and disease resistance,and crop quality, as well as to en-hance the knowledge on the inheri-tance mechanisms of these traits.Molecular cytogenetic techniques in-volving in situ hybridisation of DNA se-quences have proven to be a valuablemethod in gaining insight to thegenome. Fluorescence in situ hybridi-sation (FISH) with multiple probes hasbeen shown to be an efficient methodfor the study of fundamental aspectsof chromosome structure and behav-iour. Genomic in situ hybridisation(GISH) allows differentiating chromo-somes from different genomes in thesame species, enabling the identifica-tion of parental chromosomes in inter-specific hybrids. Because Musa chro-mosomes are usually not entirelylabelled following GISH, it is importantto develop more molecular cytoge-netic landmarks that will contribute tothe construction of physical maps andpermit integration of genetic and phys-ical maps including the analysis byFISH of the 18S-5.8S-25S and 5SrDNA sequences as well as the telom-eric sequences.

Genetic transformation of bananasmay also highly contribute to the cre-

ation of new clones resistant to pestsand diseases. However, even if ge-netic transformation protocols havebeen successfully developed in differ-ent institutions, allowing to regeneratetransformed banana plants with anti-fungal protein genes, and anti-viralgenes, specific banana genes andpromotors are also needed.

Different approaches for discoveringgene sequences and functions can bepursued, each with specific advan-tages and shor tcomings: the ex-pressed genes of a plant can be cata-logued by sequencing expressedsequence tags (ESTs) or complemen-tary DNA (cDNA). There are morethan 100,000 plant ESTs available inpublic databases, which offers an effi-cient method for gene discovery inplants. A comparison of EST data-bases from different plants, tissuesand conditions reveals the diversity incoding sequences between plants. Atthe same time, however, it provides aglobal perspective of the similarities ingenes for specific processes, such asripening conditions, or the induction ofpathogens. A sequence similarityanalysis using bioinformatics toolspermits the assignment of probablegene function and the identification ofgenes that are similar betweenspecies.

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