Abstract

The effectiveness of 11 commercial insecticides was tested by direct application to the beetles and by application to their food surface. HCH, lindane, cypermethrin and permethrin were the most toxic to the beetles. With the exception of HCH and lindane, organochlorines were less toxic than organophosphorus insecticides, carbamates and pyrethroids. DDT was the least toxic. Boric acid was also tested, but was ineffective when sprayed over the insect or the food surfaceit was toxic when incorporatedinto the diet