Insecticides for control of light brown apple moth and codling moth in Australia

Spray treatments of chlorpyrifos, chlorpyrifos-methyl, leptophos, mexacarbate, Bacillus thuringiensis and standard recommendations for control of Epiphyas postvittana Walk. and Cydia pornonella (L.), were compared in six field experiments on apples in Victoria and Tasmania in 1971/72 and 1973/74 and in New South Wales in 1971/72. In all four experiments in southern Victoria and Tasmania, chlorpyrifos 250 p.p.m. applied at two week intervals from calyx formation was as effective against E. postvittana as the standard azinphos methyl, In the same region chlorpyrifos-methyl 500 p.p.m. gave results as good as the standard in two experiments and mexacarbate 500 p.p.m. and Bacillus thuringiensis 37.5 g 100 l-1 in one. Alternate sprays of B. thuringiensis 25 g 100 l-1 and either chlorpyrifos 375 p.p.m. or leptophos 375 gave results as good as the standard in two experiments. Azinphos methyl 375 p.p.m. sprays alternated with B. thuringiensis 25 g 100l-1 gave results as good as the standard in a single experiment. In one experiment, leptophos 500 p.p.m. gave better control than the standard. In two experiments in central and southern Victoria, chlorpyrifos 250 p.p.m. applied every two weeks from calyx formation was as effective against C. pornonella as the standard azinphos methyl treatment. Leptophos 500 p.p.m. used at four- and two-week intervals in central and southern Victoria respectively gave results equal to the standard which were also equalled by chlorpyrifos 250 p.p.m. and 375 p.p.m. respectively applied every two weeks. In an experiment in NSW with spray applications at four-week intervals from calyx formation, chlorpyrifos 500 p.p.m. was not as effective against C. pornonella as the standard azinphos methyl treatment. Chlorpyrifos methyl 500 p.p.m. and mexacarbate 500 p.p.m. did not reduce damage below the untreated. Leptophos 500 p.p.m. was as effective as the standard.