Generating Base Line Data for Insecticide Resistance Monitoring in Spodoptera litura (Fabricius)

The base line susceptibility response to five commonly used insecticides viz., endosulfan, chlorpyrifos, profenofos, fenvalerate and deltamethrin in Spodoptera litura (Fabricius) field population from rainfed growing groundnut area of Madurai district (Alagarkovil) in Tamil Nadu, was determined by topical application. LD₅₀(s) were calculated as 0.7628, 0.0355, 0.3710, 0.0672 and 0.0647 ppm for endosulfan, chlorpyrifos, profenofos, fenvalerate and deltamethrin, respectively.