EVALUATION OF INSECTICIDE EFFICACY AGAINST COTTON APHIDS, 2001

Selected insecticides were evaluated for control of cotton aphids in a commercial cotton field in Oktibbeha County, Mississippi. Treatments were replicated four times in a RCB design. Rows were planted on 38-inch row spacing, and each plot was four rows wide by 50 ft long. All treatments were applied on 12 Jul using a CO2-powered backpack sprayer calibrated to deliver 10 gpa total volume at 40 psi through 8002 nozzles spaced 19 inches apart. Plants were in the 9 node stage of development. Pretreatment counts averaged 27.3 aphids per leaf. Treatments were evaluated at 2 and 4 DAT by randomly selecting 20 leaves per plot (5th leaf below terminal), counting the number of aphids present, and calculating the average number of aphids per leaf. No rainfall occurred during the time the trial was being conducted.