Resistance to Pyrethroids in Helicoverpa armigera (Lepidoptera: Noctuidae) from Corn: Adult Resistance, Larval Resistance, and Fitness Effects. Issue 5 (24th September 2014) - Glenn, Deann C.
Abstract : Although Helicoverpa armigera (Hübner) is a major pest of sweet corn and other vegetable crops in Australia, not much is known about resistance to pyrethroids in these crops. We sampled populations of H. armigera from sweet corn at four sites in Victoria, Australia, and tested for resistance to fenvalerate by using a diagnostic dose in an adult vial test. Resistance frequencies were as high or higher than those in the cottongrowing regions of northern Australia, where resistance to pyrethroids has been recognized since 1983. The magnitude of resistance of adults and larvae from various sites was also comparable in range and variablility to that in H. armigera strains from the cottongrowing regions even though insecticides are used more intensely in cotton. Adults were much more resistant to fenvalerate than larvae. We detected no significant differences in the development times and pupal weights of resistant and susceptible H. armigera . We discuss implications of these results for management of insecticide resistance in H. armigera on corn.