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PESTS OF COTTON :: Major Pests :: Leafhopper1. Leafhopper: Amrasca devastans (Cicadellidae: Hemiptera)
Distribution and status: Major pest in all cotton-growing region of India
Host range: Cotton, potato, brinjal, castor, bhendi, tomato, hollyhock and sunflower.
Damage symptoms: Both nymphs and adults suck the sap from the under surface of leaves, tender leaves turn yellow, leaf margins curl downwards and reddening sets in. In the case of severe infestation leaves get a bronze or brick red colour which is typical “hopper burn”. Crop growth retarded.
ETL: 50 nymphs / adults per 50 leaves or yellowing and curling from the middle to upper portion of the plants in 25 % of plants in the field
Bionomics: Adult green and wedge shaped, lay eggs singly within leaf veins. Incubation period 4-11 days. Nymph light green and translucent found between the veins of leaves on the under surface. Nymphal period 7-21 days. Nymphs moult five times. Life cycle is completed in 15-46 days. Eleven generations are known to occur in a year.
Management
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