Foliar Sprays for Control of Colorado Potato Beetles, Test 7, 1978

Abstract

Abstract ‘Russet Burbank’ potato seed pieces were planted on Mar 30 in Ritzville silt loam soil with a pH of 6.2 and 1.6% organic matter at Yakima, WA. Each plot was 2 rows wide (5.6 ft) and 25 ft long. On Jun 15, the insecticides were applied in 40 gal of water/acre with a 2-row portable boom CO2hand sprayer with 4 (TeeJet AL80015) nozzles spaced 17 inches apart. The potato plants were 12-14 inches high and the plants were naturally infested with Colorado potato beetle (CPB) at the time of insecticide application. Each treatment was replicated 2 times in a randomized complete block design. On Jun 16 (20 hours after treatment) 10.8 ft2 of soil surface between the 2 treated rows at each of 2 locations in each plot was searched, and the number of dead and live CPB adults and larvae on the soil were counted. On Jun 16 (20 and 24 h after treatment), and on Jun 19 (96 h after treatment), the potato plant foliage on 10.8 ft2 at each of 2 locations in each plot was examined, and the number of adults and larvae on the plants were counted. The percent control was calculated for each plot by Abbott’s Formula based on the number of live CPB found on the soil surface and the plant foliage per plot in the untreated and treated plots.