Comparative efficacy of some biopesticides and insecticides against diamondback moth, Plutella xylostella (L.) on cabbage in Allahabad, U.P.

In order to determine the comparative efficacy of some biopesticides (Azadirachtin, Bt. kurstaki and spinosad) with recommended insecticide-quinalphos against diamondback moth, Plutella xylostella (L.). Field trial was conducted during rabi season 2009–10 at Allahabad, U.P. The insecticides were used as per recommended doses along with an untreated control. Each insecticide was sprayed thrice at 15 days interval. The larval count per plant was taken day before and 1, 7 and 14 days after each spray. All the insecticides tested significantly reduced the pest population compared to control. Quinalphos 25 EC @ 1000 ml/ha was the most effective on the basis of pest population per plant and increase of yield over untreated control.