Arthropod abundance in an Australian apple orchard under mating disruption and supplementary insecticide treatments for codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae)

The impacts of three codling moth management strategies (i, mating disruption alone; ii, mating disruption plus azinphos-methyl; iii, mating disruption plus fenoxycarb) on some secondary pests and their natural enemies in an apple orchard were compared over two growing seasons: 1993/1994 and 1994/1995. In the absence of azinphos-methyl (strategies i and iii), two-spotted mite ( Tetranychus urticae ) was controlled by Typhlodromus occidentalis and populations of generalist predators (e.g. ladybirds, lacewings and earwigs) increased. The populations of a parasitoid of woolly aphid ( Eriosoma lanigerum ), Aphelinus mali, also increased but not enough to provide adequate control of the aphid. Combined damage caused by lightbrown apple moth ( Epiphyas postvittana ), budworms ( Helicoverpa spp.) and San José scale ( Quadraspidiotus perniciosus ) was significantly higher in the absence of azinphos-methyl in 1994/1995. Beneficial insect populations were not suppressed by fenoxycarb. In 1994/1995, mating disruption plus fenoxycarb produced better control of E. postvittana than mating disruption alone. During transition to an apple integrated pest management program based on codling moth mating disruption, fenoxycarb was shown to be less disruptive to any natural control of secondary pests than azinphos-methyl.