Soil and Foliar Insecticides on Colorado Potato Beetles And Defoliation in Potato, 1995

Abstract

Abstract The trial was conducted at the Panhandle Research and Extension Ctr., Scottsbluff, NE, on a drained sandy loam with a pH of 7.5 and 1% organic matter. Fertilization was 150 lb N/acre, 100 lb P/acre, no potassium or sulfur. Plots were double rows spaced 36 inches and 40 feet long. Treatments were replicated five times in a latin square design. Precut, TOPS 2.5D-treated potatoes variety ‘Atlantic’ were planted on 12 May in soil at 45-50 deg F. Turbo was applied at emergence for weed suppression. Spring (Apr-Jun) was unusually wet and cold while Aug was unusually hot and dry. Irrigation was by a Lockwood Linear Move (overhead sprinkler) system applying ½ inch per week during tuber bulking. Thimet 20G and Admire 2F were applied in a band into the furrow prior to seedpiece drop. Foliar treatments, Asana XL and Provado 1.6F, were applied on 13 Jul (38 days after plant emergence) above canopy in 20 gal/acre. CPB population and defoliation were rated on a visual scale from 0 (no beetles) to 10 (totally covered with beetles), and 0 to 100%, respectively, by two people. Readings were taken at foliar treatment, 11, 18 and 25 DAT.