Evolution of Resistance to Pyrethroids in Heliothis armigera (Hübner) (Lepidoptera: Noctuidae) in Australia

Abstract
Resistance to pyrethroids evolved in Heliothis armigera (Hübner) in Australia in the early 1980s. A number of hypotheses about the evolution of this resistance in the Emerald Irrigation Area are evaluated. We conclude that field failures are not an automatic consequence of the presence of resistance alleles, that resistance was not detected earlier because of a combination of a number of factors, that the relationship between the drought in the early 1980s and resistance is not clear, and that Emerald was unlikely to be the source of resistant individuals present elsewhere in Australia.