Studies on Insecticide Resistance in Helicoverpa armigera (Hubner) in Gujarat State
Bio-assay studies were conducted at Gujarat Agricultural University campus, Anand during 1998–99 to determine the extent of resistance developed by Helicoverpa armigera (Hubner) against different insecticides in Gujarat state. Populations of H. armigera form Modasa (District Sabarkantha) and Mahudha (District Kheda) of North and Middle Gujarat were tested against nine different insecticides and higher level of resistance (13.81 to 48.57 fold) was found in populations of both the locations against cypermethrin, chlorpyriphos, carbaryl and fenvalerate.