Biological activity of neem against the red pumpkin beetle,Aulacophora Foveicollis

Abstract

The biological activity of neem on the red pumpkin beetle,Aulacophora foveicollis Lucas, was studied. The effective concentration for 50% antifeedant activity was 0.01% methanolic neem seed kernel extract (NSKE) and 0.4% neem oil, using leaves of muskmelon as feeding substrate. No-choice feeding of adults for a period of 11 days on leaves of muskmelon treated with 0.5-2.0% NSKE led to nearly 50% mortality within 4-7 days, whereas there was no mortality of adults fed on as high as 2% neem oil. The antifeedant activity of NSKE was found to vary with curcurbitaceous hosts. Neem oil as a residual film had an LC50 of 0.7%. Unlike most chemical insecticides, 1% aqueous NSKE was not phytotoxic to the 5-day-old cotyledon stage and to 15- and 35-day-old crop stages of muskmelon, whereas 1% neem oil was toxic to the 5-day-old cotyledon stage and 15-day-old crop of muskmelon, but not to the 35-day-old crop.