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Introduction
- Sunflower (Helianthus annuus L.)
has contributed significantly to the increased oilseed production in
the country during nineties.
- The cultivation of sunflower which was
confined to southern part of the country has now expanded to northern
part.
- A diverse assemblage of both beneficial
and harmful insect species are associated with sunflower crop.
- As many as 251 insect and acarine species
are known to attack sunflower crop worldwide.
- In India, more than fifty insect species
have been found feeding on sunflower of which seedling pests, cutworm
(Agrotis spp) and grasshopper (Atractomorpha crenulata),
soil insects (termites and whitegrubs), sucking pests such as leaf hopper
(Amrasca biguttula biguttula), whitefly (Bemesia tabaci),
thrips (Scirtothrips dorsalis), defoliators like Bihar hairy
caterpillar (Spilosoma obliqua), tobacco caterpillar (Spodoptera
litura), green semilooper (Plusia orichalcea), cabbage semilooper
(Trichoplusia sppi) and capitulum borer (Helicoverpa armigera)
are of economic importance.
- Non insect pests such as rabits, parakeets,
doves, house sparrows, crows, rats etc. have been reported to cause
severe damage on sunflower.
- However, the number of species of major
pests requiring management strategy vary from region to region.
- Various pest species damage different
parts of sunflower plant.
- Soil insects damage roots and emerging
seedlings.
- Defoliators and sucking pests cause loss
in food reserves.
- Infloresence pests destroy floral parts,
ovaries and developing seeds and cause direct damage.
- Storage insect pests damage endosperm
and embryo thereby prevent their proper germination and depress quality
and quantity of seed oil.
- Damage by insects predisposes plants to
various diseases through affected parts.
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