Pear: Pest Control, 1983

Abstract

Abstract Twenty-year-old pear trees were sprayed with handguns operating at 600 lb/in2 to evaluate pesticides for control of pear pests. Plots consisted of five two-tree replicates in randomized block design. Treatments were evaluated for pear psylla control by counts of adults and nymphs at 2-week intervals. Adults were counted by taking five beating-tray samples per rep. Nymphs were counted from 50-leaf samples per rep. The proximal, distal, and three leaves from between were collected from each of 10 randomly selected shoots. Phytophagous mites were counted from the same leaf samples but mite data are presented for only those dates when populations were dense enough to show differences between treatments. Leaf samples were brushed and resulting slides were examined using a dissecting microscope. Two 10-fruit samples per rep were weighed and tested for firmness with a penetrometer. Soluble solids were measured with a refractometer on samples of the combined juice of each lot of 10 fruit. Pear psylla russet and pear rust mite russet were rated according to US grade standards for fresh market Bartlett pears on samples of 25 fruit per rep. Fruit and foliage were examined for phytotoxicity after each spray date.