Colorado Potato Beetle and Green Peach Aphid Control with Soil Applied Insecticides and Foliar Sprays, 1996

Experimental plots were established on the UI Research and Extension Center, Kimberly, Idaho. Potatoes were planted on 25 Apr and irrigated by solid set sprinkler. The soil type was Portneuf silt loam. Eight treatments and one untreated check plot were replicated four times in a RCB design. Individual plots were 4 rows (36 inch row spacing) wide by 25 ft long with 5 ft alleyways separating the plots. Green peach aphids were mass reared on greenhouse sweet pepper plants (‘California Wonder’) for release into individual plots. Aphid releases were made into test plots on 27 Jun and again on 8 Jul. A total of four heavily infested plants were released per plot. On a weekly basis, adults, large larvae (3-4 instar), small larvae (1 -2 instar), and egg masses of CPB were counted and percent defoliation assessed from whole plant inspections of the center 5 hills of the middle 2 plot rows. GPA counts were made on 20 leaves chosen at random from the top, middle and bottom sections of plants in the center two rows of each plot. Admire treatments were applied at plant in-furrow over the seed piece on 25 Apr. Temik and Thimet were applied in-furrow with the seed piece also at planting. Furadan was applied in a six-inch banded S over the plants at 4-inch rosette stage of plant growth on 4 Jun using a CO2 pressurized backpack sprayer. All foliar treatments were broadcast on 29 Jun using the backpack CO2 sprayer at a rate of 20 gpa (30 psi, with 4, 10X hollow cone nozzles). On 11 Jul, a second foliar application of Metasystox-R + Asana, Monitor and Alert was made. Data were analyzed using ANOVA and Newman-Keuls multiple means comparison.