Apple, Seasonal Control of Fruit Pests, 1985

Abstract

Abstract Danitol was evaluated for its ability to provided seasonal control of codling moth and other apple pests. This test was conducted in a 15-year-old apple orchard with under-tree irrigation. The experimental design was a randomized complete block with 5 single-tree replicates per treatment. Materials were applied in a dilute spray to the point of drip (approximately 400 gal per acre) with a handgun sprayer operating at 400-500 psi. One application was made in the delayed dormant (dd) period (10 Apr) combined with 4 gal of spray oil per acre. The check was treated in the delayed dormant period with 8 gal of spray oil per acre. There were no subsequent insecticide applications to the check. Two applications were made against first generation codling moth. The first was timed to coincide with predicted 3% egg hatch or 250 degree days following first moth (23 May). The second was made 21 days following the first (13 Jun). One application was made against second generation and timed at 1290 degree days after first moth (19 Jul). All fruit on each tree were examined after first generation of codling moth was complete. Numbers of entries were recorded. At harvest (23 Sep) all fruit(or a maximum of 400) from each tree were examined and numbers of injured fruit recorded. Mites were sampled bi-weekly from mid-Jun through Sep. Fifty leaves were collected from each treatment (10 per tree), brushed in a mite brushing machine and the mites of each species counted. At harvest terminals infested with green apple aphid were counted and recorded. Woolly apple aphid densities were estimated by examining 10 shoots per tree and counting colonies observed. Densities of white apple leafhopper were determined by counting nymphs and caste skins on 10 leaves per tree.