Effect of Insecticides on Cotton Aphid, Aphis gossypii Glover (Homoptera : Aphididae)

Three insecticides, malathion, sumithion and phorate were tested against Aphis gossypi Glover in different concentrations and observations were recorded after twelve and twenty-four hours on aubergine leaf.The result was much better in case of phorate, less with sumithion and much less with malathion.LD 50 values for phorate, sumithion and malathion were 17.59, 108.07 and 364.05 µg after 12 hours and were 4.493, 45.457 and 178.38 µg after 24 hours respectively.