Determination of LC[50] of chlorpyrifos and neem extract on third instar larvae of house flies and their effect on fecundity

Two pesticides one from OP compound [Chlorpyrifos] and other from Biopesticides [Neem extract] were applied against 3[rd] instar larvae of house flies by contact method. LC[50 of Chlorpyrifos and Neem extract was calculated as 0.25% for chlorpyrifos and 0.42% for Neem Extract. Treated larvae when succeeded to reach the adult stage, the effects of the mentioned insecticides were noted on fecundity of adults of Musca domestica. Chlorpyrifos delayed egg-laying while Neem extract completely inhibited the egg-laying. Moreover, the treated larvae when succeeded to pupate, they failed to emerge from the pupal case completely and the larvae got heavy melanization after 48 hours of treatment