INSENSITIVE ACETYLCHOLINESTERASE AND RESISTANCE TO THIODICARB IN AUSTRALIAN HELICOVERPA-ARMIGERA HUBNER (LEPIDOPTERA, NOCTUIDAE)

Thiodicarb resistance was diagnosed in a field strain of Helicoverpa a rmigera from Tamworth, New South Wales in March 1993. This is the firs t record of H. armigera resistance to thiodicarb. Bioassays after sele ction in the laboratory indicated that the thiodicarb resistance facto r was greater than 40-fold and was associated with cross resistance to methomyl. Insensitive acetylcholinesterase was identified as a resist ance mechanism. Potential resistance management tactics and opportunit ies for biochemical resistance monitoring are discussed. (C) 1996 Acad emic Press, Inc.