Deterrent effect of Calotropis procera R. Br. on feeding, oviposition and egg hatchability of Plutella xylostella (L.) (Lepidoptera: Plutellidae)

Deterrent effect of aqueous, methanol and hexane extracts of Calotropis procera leaves was evaluated on the feeding and ovipositional response of diamondback moth (DBM), Plutella xylostella, in no-choice and choice bioassays under standard laboratory conditions. Concentration-dependent reduction in feeding was observed when the fourth instar DBM larvae were offered extract treated cauliflower leaf discs in both the bioassays. Antifeedant Index values obtained for aqueous (R2 = 0.9338), methanol (R2 = 0.8298) and hexane (R2 = 0.9068) extract were positively correlated with increasing concentrations. Moreover, the eggs laid by female diamond-back moth on cauliflower leaves treated with test extracts were also found to be significantly lowered in a dose -dependent manner in no-choice and choice conditions. The Oviposition Deterrent Index values increased significantly at different concentrations of a particular test extract. The percent hatchability of eggs treated with hexane extract concentrations was significantly reduced compared with untreated eggs. However, aqueous and methanol extracts showed no effect on the egg hatchability. This initial study evaluates the potential of foliar extracts of C. procera for manipulating behavioral aspects of DBM for sustainable management of this pest.