H OST - RANGE STUDY ON THE STEM - BORING WEEVIL (L ISTRONOTUS SETOSIPENNIS (C OLEOPTERA : C...
-
Upload
damon-hadaway -
Category
Documents
-
view
216 -
download
2
Transcript of H OST - RANGE STUDY ON THE STEM - BORING WEEVIL (L ISTRONOTUS SETOSIPENNIS (C OLEOPTERA : C...
HOST-RANGE STUDY ON THE STEM-BORING WEEVIL (LISTRONOTUS SETOSIPENNIS (COLEOPTERA: CURCULIONIDAE) FOR THE CONTROL OF PARTHENIUM HYSTEROPHORUS IN ETHIOPIA
By Sintu Alemayhu
OBJECTIVE
To evaluate the safety of the stem-boring
weevil, Listronotus setosipennis non-target
plant species
DESCRIPTION AND LIFE CYCLE
stem boring weevil Listronotus setosipennis
(Hustache) [Coleoptera: Curculionidae] originally
from Argentina, were introduced from Agricultural
Research Council-Plant Protection Research
Institute (ARC-PPRI) of South Africa in December
2009, to be used for studies in Ethiopia
Nocturnal adults feed on leaves and flowers
Lay eggs in flower heads or leaf bases
hatch 3-5 days later
pupate in soil inside fibrous capsules
Listronotus setosipennis (Coleoptera: Curculionidae
Complete life cycle of Listronotus takes 30-35 days.
DAMAGE
o Adult feeding damage is negligible.
o Larval feeding has the ability to kill or prevent
further development of parthenium seedlings.
In glasshouse conditions, infestation by
Listronotus weevil at high densities significantly
reduced the plant biomass by 21.9% and flower
production by 75%.
HOST SPECIFICITY
o Host specificity testing is a critically important step
in the process of introducing natural enemies for
classical weed biological control.
o It provides information upon which the suitability of
a proposed biological control agent can be
assessed (Marohasy1998).
CONT…
Evaluation of the host range of any bioagent comprises of
no-choice tests (test plant species only), followed by
choice tests (test plant with Parthenium) if feeding,
oviposition or development is observed under no-choice
testing on non-target species
The safety of Listronotus setosipennis (Hustache) to non-
target plants was tested under quarantine on
economically important members of the Asteraceae family
and indigenous weed species through no-choice tests
SELECTION OF NON-TARGET SPECIES
The selection of non-target species for host preference testing
was made by a taxonomist from Addis Ababa University.
The centrifugal phylogenetic method was followed in selecting
test plants for testing candidate control agents
The test plant species were identified based on how closely
related they are to Parthenium, whether they are strictly
endemic, near endemic, cultivated, or indigenous to Ethiopia.
Figure 1. Diagrammatic representation of the tribe Heliantheae and some crop plants (adapted by Lorraine Strathie from Wapshere, A. J. 1974).
MATERIALS AND METHODS
Area description
The experiment was conducted under quarantine
condition at Ambo Plant Protection Research
Center (APPRC) 109km West of Addis Ababa.
The average temperature is ranges from 10o to
30o C and relative humidity at 50-87 % in the
quarantine facility
CULTURING OF L. SETOSIPENNIS
Adult feeding and oviposition were tested using nylon mesh test cages with metal frames(0.5m x 0.5m x 1m), with two holes for potted plants.
All corners and joints were sealed with silicone to prevent escape of weevils through gaps.
The safety of Listronotus setosipennis (Hustache) to 39 non-target plants consisting of nineteen major crop species mostly used as
food and export Twenty crops and other plant species, belonging
to the family Asteraceae which includes two species of Helianthus annus , six species Guizotia abyssinica, both of which are important oil crops in the country . and four species of Bidens
CONT…
o No-choice tests were designed to test whether the bio-agent
feeds, lay eggs and survive on a test plant when it has no
access to target weed Parthenium.
o All the test plants were grown or transplanted into plastic
pots(22cm X 18 cm), containing the mixture of sand 25%,
compost/humus 25% and 50% soil
o grown up to the required test stage by providing every
agronomic management under lath-house
CONT…
o Healthy and similar size Plant with flowers, were
selected and placed in a cage after being washed
o Five mating pairs of adult L. setosipennis, obtained
from same age group of adults that had been kept for
2-3 weeks, were released into each cage.
o Sodium hypochlorite solution (2%) was sprayed on
the leaves and soil to prevent any disease occurrence.
o The experiment was replicated three times in CRD
and one plant per cage was used.
CONT…
After 7 days of exposure all adults were removed
from each test plant and the number of adults that
survived, died and missed was recorded
All plant parts, including leaf axils, stems and
petioles, were carefully examined for ovipostion and
feeding. Eggs were counted after dissecting flowers
and examining plants under a microscope.
• The blue arrow shows frass • The read arrow shows egg
Tagetes minuta Helianthus annus (oissa)Bidens pachyloma
G.abysinica (kuyyu)
Vernonia galamensis
No Scientific Name Common name / variety
Total no of egg
Total mean S.D S.E
Parthenium hystrerophorous (control)
partehnium 8648 38.96 50.01 3.37
1. Eragrostis tef Teff 0 0 0.00 0.002. Eragrostis tef Teff v DZ-c37 0 0 0.00 0.003. Sorghum bicolor Sorghum 0 0 0.00 0.004. Zea mays Maize 0 0 0.00 0.005. Hordeum vulgare Barley 0 0 0.00 0.006. Triticum aestivum Wheat 0 0 0.00 0.007. Cicer arietinum Chick pea 0 0 0.00 0.008. Lens cultinaris Lentil 0 0 0.00 0.009. Gossipium sp. Cotton var, Arba 0 0 0.00 0.0010.
Sesamum indicumSesame
0 0 0.00 0.00 var. Abasena11. Sesamum indicum var. Tate 0 0 0.00 0.0012. Sesamum indicum var.5 0 0 0.00 0.0013. Pisum sativum L. Field peas 0 0 0.00 0.0014. Vicia faba Faba beans 0 0 0.00 0.0015. Lathyrus sativus Grass pea, Indian vetch 0 0 0.00 0.00
16. Solanum tuberosum Potato local 0 0 0.00 0.0017. Solanum lycopersicum Tomato 0 0 0.00 0.0018. Capsicum sp. Pepper 0 0 0.00 0.0019 Corchorus sp. 0 0 0.00 0.00
Table 1. Result of Host-Specificity of Listronotus setosipennis (Hustache) on major crops
Evaluation of species related to PartheniumNo Scientific/variety name Common name Total no of
egg Total mean S.D S.E
1. Guizotia abyssinica (Local) niger seed 0 0 0.00 0.00
2. G. abyssinica (Fogera) niger seed 0 0 0.00 0.00
3. G. abyssinica (ESTE) niger seed 0 0 0.00 0.00
4. G. abyssinica (Kuyu) niger seed 0 0 0.00 0.00
5. G. abyssinica (Shambu) niger seed 0 0 0.00 0.00
6. G. abyssinica (Ghinchi) niger seed 0 0 0.00 0.00
7. Helianthus annuus (oissa) sunflower 0 0 0.00 0.00
8. Helianthus annuus (R.B) sunflower 0 0 0.00 0.00
9. Carthamus tinctorius Safflower 0 0 0.00 0.00
10. Vernonia galamensis Iron Weed 0 0 0.00 0.00
11. Lactuca sativa Lettuce 0 0 0.00 0.00
12. Bidens pilosa Black jack 0 0 0.00 0.00
13 Bidens Pachyloma Adeyabeba (Amharic) 0 0 0.00 0.00
14 Bidens ghedoensis 0 0 0.00 0.00
15 Bidens sp 0 0 0.00 0.00
16 Guizotia scabra Metch (Amharic) 0 0 0.00 0.00
17. Conyza bonariensis Horseweed, Asthmaweed 0 0 0.00 0.00
18. Galinsoga parviflora Gallant soldier 0 0 0.00 0.00
19. Tagetes minuta Black mint 0 0 0.00 0.00
20. Flaveria trinervia Clustered yellow tops 0 0 0.00 0.00
21. Parthenium hysterophorus parthenium 8648 38.96 50.01 3.37
CONCLUSION
The concern that the agent, Listronotus setosipennis, might attack non- target crops and plants was resolved through a quarantine test against crops and plants that are closely related to Parthenium and others that are economically important and indigenous to Ethiopia.
Therefore there was no need to go for choice test since no oviposition took place in no choice test
Thank You