First year results of the impact of a novel pest management technology on apple fruit quality.

摘要

A new, 'reduced risk' biopesticide, kaolin, is commercially available as a potential replacement for insecticides that manage key apple insect pests. When kaolin is sprayed onto the tree, it forms a physical barrier that repels insects or makes the site unrecognizable and/or unsuitable. Initial research indicated that kaolin also might have non-target impacts such as a reduction in heat stress and a reduction in canopy temperature. However, most of the research on non-target effects, such as impacts on fruit quality, has been conducted in warmer, semiarid environments. These potential impacts may not be beneficial in cooler orchard environments. One of the objectives of this three-year study is to determine the effects of kaolin-based particle film on fruit quality. Five treatments were applied yearly to the plots: (1) kaolin starting at the Silver Tip growth stage and continuing on a weekly schedule through petal fall, then bi-weekly to the end of the growing season, plus fungicides; (2) kaolin starting at Silver Tip and continuing on a weekly schedule through petal fall, then bi-weekly to the end of the growing season but trees would not receive any fungicides; (3) kaolin starting at the petal fall growth stage and continuing on a bi-weekly schedule through the end of the growing season, plus fungicides; (4) a typical IPM spray programme consisting of applications of phosmet plus fungicides; and (5) a 'control' where no insecticide (kaolin or phosmet) will be applied but trees will receive fungicides. All treatments will receive horticultural sprays (i.e., thinners, nutrient applications) according to Extension Service recommendations. The 2001 data indicate significant differences in the treatments in fruit weight, height, width, firmness and starch index. There were no significant differences in percent red colour. This study will continue through 2004 to determine kaolin's potential non-target horticultural impact under cooler growing conditions.