Developing Descriptor List for Hoya...

13

Proceeding The International Seminar on Tropical Horticulture Horticulture for The Quality of Life Bogor, December 10th, 2018

Developing Descriptor List for Hoya Plant

Sri Rahayu1*

1Center for Plant Conservation – Bogor Botanic Gardens – Indonesian Institute of Sciences (LIPI), Jl. Ir. H. Juanda 13 Bogor – 16122

*Corresponding Author: [email protected]

Abstract

Hoya (Apocynaceae, Asclepiadoideae) has been increasingly popular as ornamental plant which have very high value not only for aesthetics but also for the healthy environment. As the increasing demand of the Hoya species, the developing new variety of Hoya has been create in several countries including in Indonesia. The needs for descriptor list of this plant group should be answered. This paper is proposed the descriptor list for Hoya plant, mainly based on the morphological characteristics observation on Indonesian Hoya species and some varieties. The observation was based on plant collection in Bogor Botanic Gardens, Singapore Botanic Gardens, Goetingen Universiy Botanic Gardens, Hortus Botanicus Leiden and living collections of commercial growers in Indonesia and Thailand. There were 35 morphological characters selected for this descriptor list.

Keywords: characterization, descriptor list, Hoya, morphological characters, species, varieties

1. Introduction

Hoya is a genus in the family Apocynaceae, sub family Asclepiadoideae (Endress & Bruyns, 2000; Endress et al., 2014). This genus comprises about 400 species (Lamb and Rodda, 2016) which is distributed along the Asiatic countries to tropical Australia. The distribution ranges through India, Sri Lanka, Myanmar, Thailand, Vietnam, Cambochia, Southern China and Japan, Malaysia, Indonesia, Philippines, Micronesia, Samoa, Fiji Islands, New Caledonia, Papua New Guinea, and Northern Australia (Aurigue, 2013). Indonesia was predicted to have the highes Hoya speceis diversity (Kleijn and van Don Kelaar 2001). This genus has been increasingly popular as ornamental plant due to its interesting beautiful star shaped waxy, shiny and fragrant flowers which are rich in color and form diversity. Hoya species are not only suitable for ornamental plant for aesthetics, but also have precious value for the healthier environment. Hoya is one of the five high eficience indoor pollutant removal ornamental plant (Yang et al., 2009). Another uses of Hoya species are for medicines (Zachos, 2005; Rahayu, 2011a).

The demand for Hoya as ornamental plant is increasing along with the increasing popularity of Hoya flower. Following the species collection, hobiist are start to create new varieties in order to increase the variation and choices as well as increasing effort on Hoya domestication. In the present time, the cultivation of Hoya flower is still depend on the diversity of species provided by the nature rather than developped new cultivar. The number of Hoya species is still much larger than Hoya cultivar. The number of Hoya cultivar is stiil below 50 while the number of species is about 400 species or more. The attempt to create new cultivar is mostly to obtain new interesting color and shape and especially larger shape. The Hoya species commonly have little size with the average

14


1.5 - 2 cm in corolla diameter. Only limited species has large corolla size, such as Hoya imperialis with 3 cm in diameter and Hoya lauterbachii, which has the larger size i.e 5-8 cm in diamter (Simmonson-Juhonewe and Rodda, 2017).

The Hoya hibridization has been done and new Hoya varieties has been create in several countries including Indonesia. The success of creating new varieties and cultivars require the presence of descriptor list. The needs for descriptor list not only to characterize new varieties, but also useful for describing species and organize the species and cultivar diversity. Descriptor list will be also useful for maintaining the germplasm for conservation and utilization purpuses. Descriptor list contain standardtize information systematically and unambiguous. Descriptor lists include key attributes, characteristics or traits of a crop, and set out the method used to measure and document them, along with the relevant registration data (Biodiversity International, 2007). It is used to facilitate data classification, storage, retrieval, exchange and use. Descriptor lists therefore aim to include information and data that are relevant for different types of operations for a specific crop.

There are several sets of rules to develop a descriptor list of plant depends on the purpose of making a descriptor list. The guidelines to develop descriptor list issued by The Biodiversity International (2007) focussed on the managament of biodiversity, while Thormann et al. (2013) developped descriptor list guide for crop wild relatives and Alercia et al. (2012) developped rules for multicrop paspor descriptor. The specific descriptor list guide was alos developped by UPOV (Union Internationale pour la Protection des Obtentions Végétales) in 1989 and revised in 1993. The guidelines have been developed specifically for testing the distinctness, uniformity and stability (DUS) of new cultivars of crops (UPOV 1989, 1993). DUS traits are central to the breeder’s work since they are necessary to obtain legal protection for a bred variety.

This study was aimed to select a set of morphological characters of Hoya plant as a base to develop descriptor list for Hoya plant which in turn can be useful as a standart for Hoya characterization and other relevant uses.

2. Materials and Method

Plant material was the sort of Hoya species and varieties. This paper is proposed the descriptor list for Hoya plant, mainly based on the morphological characteristics observation on Indonesian Hoya species and some varieties. The observation was based on plant collection in Bogor Botanic Gardens, Singapore Botanic Gardens, Goetingen Universiy Botanic Gardens, Hortus Botanicus Leiden and living collections of commercial growers in Indonesia and Thailand. Additionally we use also the spcimen from herbarium sheets of Herbaria in Bogor (BO), Singapore (SING), Leiden (L), Kew (K), Paris (P), Berlin (B) FRIM Malaysia, UPM Malaysia and Edinburgh. We consider the rules and guidelines avalible i.e from the Biodiversity International (2007), and UPOV (1989 & 1993) for varieties distinctness. The order of this descriptors follow a botanical order i.e. (1) Seedling (e.g. hypocotyl colour, pubescence) (2) Plant (e.g. growth habit, crown shape) (3) Root (e.g. shape, surface, flesh colour, system) (4) Stem (length, pubescence) (5) Leaf (blade, petiole, stipule) (6) Inflorescence (7) Flower (calyx, sepal, corolla, petal, stamen, pistil) (8) Fruit (9) Seed/grain. We also follow the most immediately visible characteristic, such as: (1) Attitude (2) Colour (3) Shape (Individual parts of the organ, such as base shape, apex shape and margin) (4) Height (5) Length (6) Width (7) Other

15


characteristics. The character state for Hoya plant refer to Rahayu et al (2010) and Rahayu (2011b).

Gathering and analysing data The consideration including practical descriptors i.e.: (1) type of data, (2) type of

scale (3) resolution, compelxity and (4) scoring, coding and recording. The type of data classified into two broad categories i.e. qualitative data and quantitative data. Qualitative characteristics can be measured using nominal, ordinal or binary scales. Within the continuum view such as shape and texture, can be measured (quantitatively) using continuous scales. Quantitative characteristics are recorded by measuring, counting or weighing, and can be recorded using continuous or discrete scales (Fig.1).

Figure 1. Types of data and scale (Adopted from Biodiversity International, 2007)

Qualitative descriptors using nominal scale applied to the traits that are defined by

text by providing code numbers. They do not follow a numerical or logical order or ranking sequence and the codes are arbitrary numbers (e.g. pubescence, colour, shape). Qualitative descriptors using ordinal scale applied to the traits which have order (e.g. data values are ranked in a numerically meaningful way). Ordinal scales rank traits from low to high. Qualitative descriptors using a binary scale applied when the traits only have two categories (absent vs. present). Quantitative descriptors using a continuous scale refer to the exact measurement of a trait and can assume an infinite number of real values. The best way of recording quantitative descriptors is by scoring the measurement in exact units, using the international unit system (Système International d’Unités – SI). Conversion from a continuous scale to a discrete scale is possible, but it is not possible to convert from a discrete scale to a continuous scale. All quantitative descriptors use actual measurements. Where resources are insufficient to take actual measurements, quantitative characters that are continuously variable can be recorded on a 1–9 scale, as follows:

Continuously variable attribute 0 Absent 5 Intermediate 1 Very low 6 Intermediate to high 2 Very low to low 7 High 3 Low 8 High to very high 4 Low to intermediate 9 Very high

16


The measurement was using standartize equipment with the International Unit Sistem, and the measurement of color by using The Royal Horticultural Society (RHS) Colour Charts.

3. Results and Discussion

From the observation, we here listed 45 morphological character as descriptor list for Hoya plant (Table 1). The chart was following botanical order from plant growth habit to the leaf. We do not include pollinia and stigma for the practical uses reason. The stamen and pistil of Hoya flowers unite in structure namely gynostegium, and the pollen also unite into pollinia (Lamb and Rodda, 1996). Observation on pollinia will need the aid of specific equipment i.e. microscope and will be not easy to apply in the filed observation. The size of pollinia is small, less than 2 mm, and still hard to observ by using hand luope. The Table of Characteristics is provided in bilingual. Some characters listed in Table 1 still need to be more clearly explanained. The explanation is provided following the Table of characteristics.

Table 1. Karakteristik/Table of Characteristics

No. Karakteristik/ Characteristics

bahasa indonesia english Varietas contoh/ Example varieties

Notasi/Note

1. Tanaman: cara tumbuh Plant: Growth habit

tegak mendatar /kit tegak menggantung

upright horizontal/ semi upright pendulous

H. cumingiana H. lasiantha H. carnosa

3 5 7

2. Getah: warna Sap: coloration

putih latex bening

white latex clear

H. diversifolia and most H. uncinata,H.carnosa

1 2

3. Akar: akar adventif Root: Adventive root

Tidak ada Sedikit Sedang Banyak Banyak sekali

Absent few medium many a lot

H. narcissiflora Hoya australis Hoya diversifolia Hoya lacunosa

1 3 5 7 9

*4. Batang: bentuk Stem: shape

silindris pipih

cylindrical flat (platycaulis)

Hoya diversifolia, most Hoya Hoya platycaulis

1 2

5. Batang: jumlah daun pada perbukuan Stem: number of leaf per node

satu dua

one two

H. 16evolute16 H. carnosa

1 2

6. Daun: panjang Leaf: length

pendek sedang panjang

short medium long

H. lacunosa H. carnosa H. vitellinoides

3 5 7

7. Daun: lebar Leaf: width

sempit sedang lebar

narrow medium wide

H. linearis H. elliptica H. latifolia

3 5 7

8. Daun: bentuk Leaf: shape

jorong lonjong melanset menggaris/pinsil bulat telur bulat telur terbalik bundar menjantung menjantung terbalik

elliptic oblong Lanceolate terete ovate obovate rounded heart shape opposite heart shape

H.eliptica/H.annulata H. vitellinoides H. longifolia H. retusa, H. obovata H. diversifolia H. imbricata H. latifolia H. kerii

1 2 3 4 5 6 7 8 9

9. Daun: lengkung balik terhadap sumbu Leaf: recurvature in longitudinal axis

tidak ada atau 16evolu tidak ada lemah kuat

absent or very weak weak strong

1 2 3

10 Daun: gelombang Leaf: undulation

tidak ada atau hampir tidak ada lemah kuat


1 2 3

17


11 Daun: puntiran Leaf : twisting

tidak ada atau hampir tidak ada lemah kuat


H cv. Krinkle8

1 2 3

12 Daun: tebal Leaf : thickness

tipis sedang tebal

thin medium thick

H. lasiantha H. elliptica H. bilobata

3 5 7

13 Daun: bulu Leaf : pubescense

tidak ada ada

absen presentt

H.diversifolia H.coronaria

1 9

14. Daun: intensitas warna hijau pada permukaan atas Leaf: intensity of green color on upper side

terang sedang gelap

light medium dark

3 5 7

15 Daun: variegata Leaf: variegation

tidak ada ada

absent present

H. carnosa H. carnosa variegata

1 9

16. Daun: penyebaran 17evolute17 Leaf:distribution of variegation

di pinggir di tengah menyebar

at margin center throughout

H.kerii”albomarginata’

1 2 3

17 Daun: warna 17evolute17 Leaf:color of variegation

putih kuning hijau muda

white yellow light green

H.carnosa variegata H. kerrii variegata

1 2 3

18 Daun: urat daun Leaf:conspicuousness of vein

tidak jelas jelas

conspicuous inconspicuous

H. diversifolia H. finlaysonii

1 9

19 Hanya untuk varietas dengan urat daun yang jelas Daun : warna peruratan Only varieties with conspicuous vein: Leaf: color of vein

lebih muda dari warna daun sama lebih tua dari warna daun

lighter than leaf color same color darker than leaf color

H. elliptica H. lacunosa H. finlaysonii

1 3 2

20 Tangkai daun: pewarnaan antosianin Petiole: anthocyanin coloration

tiak ada ada

absent present

1 9

21 Perbungaan: susunan 17evolu Inflorescence:arrangement of umbel

di ujung di tengah

Terminal interpetioler

H. latifolia H. carnosa

1 2

(*)22 Hanya untuk varietas dengan payung di ujung. Perbungaan: jumlah payung pada buku Only varieties with terminal umbel: Inflorescece: number of umbels per node

satu lebih dari satu

one more than one

H. diversifolia H. latifolia

1 2

(*)23 Payung: arah menghadap Umbel: direction of umble

ke atas ke samping ke bawah

upward horizontal downward

H. mitrata H. diversifolia H. lacunosa

1 2 3

(*)24 Payung: jumlah bunga Umbel: number of flowers

sedikit sedang banyak

few medium many

H. coronaria H.lacunosa H.multiflora

3 5 7

(*)25 Payung: diameter Umbel: diameter

kecil sedang besar

small medium large

H. 17evolute H. diversifolia H. imperialis

3 5 7

(*)26 Payung: bentuk Umble: shape

cembung datar cekung

convex flat concave

H. carnosa H. annulata H. revoluta

1 2 3

18


27 Payung: keserempakan berbunga Umbel: simultaneous flowering

tidak serempak serempak

absent present

H.latifolia H. multiflora

1 9

28 Mahkota: diameter Corolla : diameter

kecil sedang besar

small medium large

H. 18evolute H. carnosa H. imperialis

3 5 7

29 Mahkota: tampak depan Corolla: front view

bundar bintang tidak beraturan

round Star-shaped irregular

H. campanulata H. carnosa

1 2 3

30 Mahkota: arah mekar terhadap tangkai bunga Corolla: direction to the pedicel

searah datar membalik

same direction horizontal reflexed

H. campanulata H. diversifolia H. multiflora

1 2 3

31 Mahkota: lengkungan mahkota Corolla:curvature of corolla lobe

ke dalam lurus ke luar

incurved flat outcurved

1 2 3

(*)32 Mahkota: kedalaman celah helai mahkota Corolla:depth of incision of corolla lobe

dangkal sedang dalam

shallow medium deep

3 5 7

(*)33 Mahkota: bulu Corolla: pubescence

tidak ada ada

absent present

1 9

34 Mahkota: jumlah warna Corolla : number of color


one more than one

1 2

35 Mahkota: warna utama Corolla : main color

putih hijau kuning oranye pink orange pink merah ungu biru

white green yellow orange pink orange pink red purple blue

1 2 3 4 5 6 7 8 9

(*)36 Mahkota : pola warna sekunder Corolla:patern of secondary color

bergaris makulata bergaris& makulata

striped maculate striped and maculate

1 2 3

37 Korona: jumlah warna Corona:


one more than one

1 2

38 Korona : warna utama Corona: main color

putih hijau kuning orange pink orange pink merah ungu biru

white green yellow orange pink orange pink red purple/violet blue

1 2 3 4 5 6 7 8 9

39. Buah: bentuk Fruit :shape

Menggaris/pinsil Lonjong membulat

terete oblong rounded

1 2 3

40 Buah: ukuran panjang Fruit: length

Pendek Sedang panjang

Short Medium long

1 5 9

41 Buah: Diameter Fruit: diameter

Kecil Sedang besar

Small Medium large

1 5 9

42 Buah: kulit : kerutan Fruit: skin : wrinkles

Tidakada Sedang Banyak

Absent Medium many

1 5 9

43 Buah: kulit: pewarnaan antosianin Fruit:skin anthocyanin coloration

Tidak ada Ada

Absent present

1 2

19


44. Biji: Bentuk Seed: shape

Pipih menjarum

Flat Needle form

1 2

45. Biji: ukuran Seed: size

Kecil Sedang Besar

Small Medium large

1 2 3

Penjelasan Tabel Karakteristik Explanation of Tabel Characteristics Ad 4. Batang: jumlah daun pada perbukuan Ad 4. Stem: number of leaf per node

1. Satu 1. One

2. Dua 2. Two

Ad 6. Daun: Panjang Ad 6. Leaf: lenght

Sifat/state Notasi/ note Data kuantitatif/ Kuantitatif score

pendek sedang tinggi

short medium

tall

3 5 7

< 5, 5-10,

>10 cm

Ad 7. Daun: Lebar Ad 7. Leaf: Width


pendek sedang tinggi

short medium

tall

3 5 7

< 5, 5-10,

>10 cm

20


Ad 8. Daun: Bentuk Ad 8. Leaf: shape:

1. elips 2. lonjong 3. lanset 4. pinsil 5. bulat telur 1. elliptic 2. oblong 3. lanceolate 4. terete 5. ovate

6. bulat terbalik 7. bundar 8. menjantung 9. menjantung

terbalik 6. obovate 7. rounded 8. heart shape 9. opposite heart

shape Ad 21. (Penjelasan khusus untuk karakter Hoya no.21-22) Ad 21. (explanations on special characteristics no.21-22)

21


Ad 23. Payung: arah menghadap Ad 23. Umble: direction

1. ke atas 2. ke samping 3. ke bawah

1. upward 2. horizontal 3. downward

Ad 24. Payung: Jumlah bunga Ad 24. Umble: Number of flowers


sedikit sedang banyak

few medium

many

3 5 7

< 10, 10-20, >20 cm

Ad 25. Payung: diameter Ad 25. Umble: diameter


kecil sedang besar

small medium

large

3 5 7

< 3, 3-5,

>5 cm

Ad 26. Payung: Bentuk Ad 26. Umble: Shape

1. cembung 2. datar 3. cekung 1. convex 2. flat 3. concave

22


Ad. 28-38 (penjelasan untuk karakter khusus Hoya nomor 28 sampai 38) Ad. 28-38 (explanations on special characteristics no 28 - 38)

Ad 28. Mahkota: Ukuran diameter mekar Ad 28. Corolla: Size of opened flower


Kecil sedang Besar

litle medium Large

3 5 7

Kecil sedang Besar

Ad 29. Mahkota: Tampak depan Ad 29. Corolla: opened flower front view

1. membundar 2. membintang 1. round 2. star shaped

Ad 30. Mahkota: arah mekar terhadap tangkai bunga Ad 30. Corolla: direction to the pedicel

1. searah 2. datar 3. membalik

Gynostegium (stigma)

Gynostegium (Anther wing)

Mahkota / Corolla

Korona/Corona

Gantilan/pedicel

23


1. same direction 2. horizontal 3. reflexed

Ad 32. Mahkota: kedalaman celah helai mahkota Ad 32. Corolla : depth of incision on corolla lobe

1. dangkal 2. sedang 3. dalam 1. shallow 2. medium 3. deep

Ad 36. Mahkota: Pola warna mahkota Ad 36. Corolla: pattern of coloration

1. bergaris 2. makulata 3. bergaris dan makulata 1. stripped 2. maculate 3. stripped and maculate

The table of characteristics and explanation can be use and similar to the technical

guidelines developed by the Union Internationale pour la Protection des Obtentions Végétales (UPOV). The technical guidelines developped by the UPOV have been developed specifically for testing the distinctness, uniformity and stability (DUS) of new cultivars of crops (UPOV 1989, 1993). DUS traits are central to the breeder’s work since they are necessary to obtain legal protection for a bred variety. But for the purpose as technical guidelines, some requirements are needed such as minimum amount of seed, number of vegetation periods, minimum number of plants, and maximum number of aberrant plants are defined. The UPOV descriptor lists are constructed with the thoroughness of legal documents. Requirements for the minimum precise rules for scoring are given, along with example varieties for each trait and level of manifestation. Many countries have adopted the UPOV guidelines for identifying and registering new plant varieties. UPOV lists contain data that correspond to Bioversity categories of characterization and preliminary evaluation. The objective and interpretable scoring of traits is a clear advantage of this system (van Hintum et al. 1995). According to Biodiversity International (2007) use of the UPOV Technical Guidelines by the plant genetic resources community is limited due to the high number of standard cultivars used and the fact that these standards are based on modern cultivars, making comparison with exotic material or wild species difficult. But in Hoya, as the cultivars is still very limited, the Table of characteristics can be develop from species observation. So this will make this Table of characteristic also useful for genetic resources management as well as develop as a test guidelines for DUS. This Table of characteristics also useful for the breeder to do self assesment to identify is their bred new or not.

24


4. Conclusion

The descriptor list for Hoya plant can be develop from the species as well as cultivar and listed 45 characters to be considered. The table of characteristics can be developped into further specific descriptor such as technical guidelines for DUS test, or for develop descriptor list for genetic resources management, depend on the pasport data and specific requirements added to the Table of characteristics.

References

Alercia A., Diulgheroff S. and Mackay M. 2012. FAO/Bioversity Multi-Crop Passport Descriptors (MCPD V.2). FAO (Food and Agriculture Organization of the United Nations), Rome, Italy and Bioversity International, Rome, Italy. http://www.bioversityinternational.org/nc/publications/publication/issue/faobioversity_multi_crop_passport_descriptors_v2_mcpd_v2.html [8 March 2013].

Aurigue. 2013. A collection of Philippine Hoya and their culture. Philipine Council for Agriculture, Aquatic and Natural Resources, Research and Development (PCAARRD). Department of Sciences and Technology.

Bioversity International. 2007. Guidelines for the development of crop descriptor lists. Bioversity Technical Bulletin Series. Bioversity International. Rome(IT).

Endress M.E., Liede-Schumann S. and Meve U. 2014. An updated classification for Apocynaceae. Phytotaxa. 159(3): 175-194.

Endress M.E. and Bruyns P.V. 2000. A revised classification of the Apocynaceae s.l. The Botanical Review. 66: 1-56.

Kleijn D and van Donkelaar R. 2001. Notes on the taxonomy and ecology of the genus Hoya (Asclepiadaceae) in Central Sulawesi. Blumea 46: 457-483.

Lamb A. and Rodda M. 2016. A Guide to Hoyas of Borneo. Natural History Publications. Sabah(MY).

Rahayu S., Jusuf M., Suharsono R., Abdulhadi and Kusmana C. 2010. Morphological variation of Hoya multiflora Blume at different habitat type of Bodogol Research Station of Gunung Gede Pangrango National Park, Indonesia. Biodiversitas. 11(4): 187-193.

Rahayu S. 2011a. Hoya sebagai tumbuhan obat. Warta Kebun Raya. 11(1): 15-21

Rahayu S. 2011b. Kekerabatan Hoya (Asclepiadaceae) Sumatra berdasarkan karakter morfologi. Buletin Kebun Raya. 14(1): 19-28.

Simmonson-Juhonewe N. and Rodda M. 2017. Contribution to a revision of Hoya (Apocynaceae: Asclepiadoideae) of Papuasia. Part I: ten new species, one new subspecies and one new combination. Gardens’ Bulletin Singapore. 69(1):97-147.

Thormann I., Alercia A. and Dulloo M.E. 2013. Core descriptors for in situ conservation of crop wild relatives v.1. Bioversity International. Rome(IT).

UPOV [Union Internationale pour la Protection des Obtentions Végétales]. 1989. Guidelines for the Conduct of Tests for Distincness, Homogeneity and Stability. Triticale (×Triticosecale Witt.). Geneva(CH).

25


UPOV. 1993. Draft Guidelines for the Conduct of Tests for Distinctness, Homogeneity and Stability. Wheat (Triticum aestivum L. emend. Fiori et Paol.). Geneva(CH).

van Hintum Th.J.L., Jongen M.W.M. and Hazekamp Th. (eds). 1995. Standardization in Plant Genetic Resources Documentation. Report of the Second Technical Meeting of Focal Points for Documentation in East European Genebanks.Centre for Genetic Resources, The Netherlands (CGN), Wageningen (NL).

Yang D.S., Pennisi S.V., Son K.C. and Kays S.J. 2009. Screening indoor plants for volatile organic pollutant removal efficiency. Hortscience. 44(5): 1377-1381.

Zachos E. 2005. Practical uses of various Hoya species. Asklepios 19(4)/20(1): 6-10/3-8.

Developing Descriptor List for Hoya...

Documents

Transcript of Developing Descriptor List for Hoya...