Survival and development of Helicoverpa armigera (Hubner) (Lepidoptera : Noctuidae) on neem (Azadirachta indica A. Juss) leaves

The survival, development and feeding responses of Helicoverpa armigera (Hu bner) on neem (Azadirachta indica A. Juss) leaflets were evaluated under ch oice and no-choice conditions. Neem leaflets provided to starving fourth-in star larvae were chewed, but larvae expectorated most of the material. The weight of surviving larvae decreased and no fourth instars completed develo pment on neem leaflets alone. Larvae resumed feeding when transferred to co tton leaves after 5 days of feeding on neem leaflets. Fourth instars strong ly discriminated between neem leaflets and cotton leaves when offered a cho ice. Early sixth instars decreased in weight and had delayed development wh en feet only on neem leaflets. Mure than one-half lived for more than 2 wee ks and some completed development to adults. Neem is an unacceptable non-ho st plant species for H. armigera.