Pyrethroid resistance of Helicoverpa armigera (Lepidoptera: Noctuidae) in Pakistan

The status of pyrethroid resistance in some field populations of Helicoverpa armigera (Hubner) from Pakistan was determined using an IRAC leaf-dip method. Resistance factors varied between populations, and the general trend was for a moderate to high resistance to cypermethrin and cyfluthrin; a low to moderate resistance to deltamethrin and alpha-cypermethrin; and a comparatively low resistance to bifenthrin, lambda-cyhalothrin and zeta-cypermethrin. Depending on which physiological mechanisms are shown to be present in Pakistani field strains, the latter group of pyrethroids may serve as useful tools in the management of insecticide resistance.