Insecticide resistance in Helicoverpa armigera (Hubner): status and prospects for its management in India

Insecticide resistance and concomitant field failures to control the cotton bollworm, Helicoverpll Ilnlzigera (Hiibner), were first recorded in south India in 1987. During the 1992-93 cropping season a discriminating dose technique ,vas used to routinely monitor resistance in four major cotton- and pulse-growing areas o f Andhra Pradesh State. Very high levels of resistance to pyrethroids, and significant endosulfan and organophosphate resistance were a feature of all regions monitored. The intensity of expression was determined by local selection pressure and mixing of populations by windborne migration agai ns t a changing background of insecticide use across seasons. Levels of piperonyl butoxide-insensitive pyrethroid resistance were hi gher in the more intensive insecticide-use regions. Farmers are applying more frequent and higher doses of insecticides, often as mixtures, in an attempt to control . (IRM) rationale, resulting in greater implementation of insecticide-resistance management control over the use of insecticides, is urgently needed to reduce the resistance selection pressure on conventional insecticides and to conserve susceptibility to ne wer insecticides and biorationals with novel modes of action. Constraints and prospects for IRM implementation in India are discussed