Pear psylla, Psylla pyricola Foerster, nymph density was related to honeydew russet on fruit of 'Bartlett' and 'Anjou' varieties. Regression analyses were performed for both peak nymph density and accumulated nymph feeding days as independent variables and damage index as the dependent variable. Damage index was based on U.S. grade standards for fresh market pears and was the sum of percent U.S. 2 grade plus two times the percent culls. These regressions projected that a peak nymph density of 0.3 nymph per leaf on both varieties produced detectable fruit damage. Eighteen and nine nymph feeding days per leaf would produce fruit injury on 'Bartlett' and 'Anjou,' respectively. Factors affecting these parameters and implications to pear pest management are discussed.
Document Type: Research Article
Publication date: April 1, 1988
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.