EVALUATION OF INSECTICIDES FOR CONTROL OF WESTERN TARNISHED PLANT BUG IN COTTON, 2008B

This test was conducted in a commercial cotton field near Wolfforth, TX. The field was planted on 24 May on 40-inch rows, and irrigated using a drip irrigation system. The test was a RCB design with four replications. Plots were 4-rows wide × 60 ft in length. Insecticides were applied with a CO2 pressurized hand-boom sprayer calibrated to deliver 10 gpa through TX-6 hollow cone nozzles (2 per row) at 40 psi. Insecticides were applied to all four rows of each plot on 23 Aug. A crop oil concentrate was added to each treatment at 1% v/v. Lygus populations were estimated on 20, 26 and 29 Aug, and 5 Sep utilizing a 36-inch × 40-inch black drop cloth. Drop cloths were laid between the rows and approximately 1.5 row-ft of cotton were shaken onto the drop cloth from each row; four drop cloth samples were taken per plot. Damage was evaluated by collecting 20, 2.75-3.25 cm diameter bolls and counting the number of external Lygus feeding stings and internal damage. All plots were hand harvested on 11 Nov using a HB stripper. An area of 1/1000 acre was harvest from the center two rows of each plot. Data were analyzed with PROC MIXED, and means were separated using an F-protected LSD (P = 0.05).