Sublethal influences of pyriproxyfen on tobacco caterpillar, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae)

Pyriproxyfen was evaluated for its sublethal influences on larvae, pupae and adults of tobacco caterpillar, Spodoptera litura (Fabricius). Significant increase in larval duration (22.15 days) and adult longevity (8.6 days in males and 7.9 days in females) was registered as compared to control. In contrast, when larvae were treated with pyriproxyfen, there was reduction in pupal duration (9.02 days), pupal weight (0.305 g), pupal size (1.258 cm length and 0.431 cm width), adult emergence (67.67%) and adult size as compared to untreated ones. The deformations were also observed in the pretreated pupae which generally become dark, reduce in size and die before adult emergence; disruption in metamorphosis was also noticed. Pyriproxyfen can prove to be a viable insecticide for management of S. litura given its promising efficacy in the field trials.