Effects of Selected Foliar Applied Insecticides on Thrips Injury and Yield of Virginia-Type Peanut, 1997

Abstract

Abstract Selected foliar applied insecticides were evaluated against TT injury and for effects on yield of Virginia-type peanut. ‘VA-C 92R’ peanut was planted 7 May at the Virginia Tech Tidewater Agric. Res. & Ext. Ctr., Suffolk, VA using 36-inch row spacing. Eight gpa of metam-sodium 42% was injected into rows as a soil fumigant on 11 Apr, about 4 weeks prior to planting. Foliar sprays were applied on 23 May, after plants had emerged, and again 10 Jun. Sprays were applied in a 12- to 14-inch band over the row with a CO2-pressurized backpack sprayer calibrated to deliver 17.0 gpa at 22 psi through one 8003 E flat nozzle over the top of each row. A RCB design was used with 4 replicates. Plots were 4 rows by 40 ft. TT injury was evaluated based on a 0 to 10 scale where, 0 = no thrips induced plant injury, 1 = 10% injured leaves, 2 = 20% injured leaves, 3 = 30% injured leaves, 4 = 40% injured leaves, 5 = ≥ 50% injured leaves + ≤ 5% terminal buds injured, 6 = ≥ 50% injured leaves + 25% terminal buds injured, 7 = ≥ 50% injured leaves + 50% terminal buds injured, 8 = ≥ 50% injured leaves + 75% terminal buds injured, 9 = a≥ 50% injured leaves + ≥ 90% terminal buds injured, and 10 = dead plants. Yield was determined by digging, drying, and combining peanuts from the 2 center rows of each plot. Data were analyzed used ANOVA and LSD procedures.