ESTERASES AND FENVALERATE RESISTANCE IN A FIELD POPULATION OF HELICOVERPA-PUNCTIGERA (LEPIDOPTERA, NOCTUIDAE) IN AUSTRALIA

A field population of Helicoverpa punctigera, resistant to fenvalerate was detected for first time in Australia on cotton in the Macquarie V alley, New South Wales in March 1994. DEF and profenofos were both par tially effective as fenvalerate synergists, but piperonyl butoxide was ineffective. Electrophoretic studies revealed that resistant H. punct igera had increased esterase activity toward l-naphthyl acetate, compa red to a susceptible strain. In vitro metabolism and enzyme binding st udies provided evidence of esterase-mediated fenvalerate metabolism. T he origin of the resistant strain is discussed, as are the implication s for insecticide resistance management. (C) 1997 Academic Press.