Determining the Relationship of Adult Moth Vial Pyrethroid Bioassays to Field Performance

Infestations of bollworms, Helicoverpa zea, commonly result in yield loss in cotton. Where economically damaging infestations occur, insecticides are commonly employed to prevent yield loss. Among the insecticides used, pyrethroids would be the optimal choice for managing bollworms due to their low cost relative to newer alternatives. However, bollworm resistance to pyrethroids is common in Louisiana. Bollworm pyrethroid resistance monitoring relies on adult vial bioassays using the pyrethroid cypermethrin.