Effect of Selected Insecticides on Beneficial Insects and Spiders in Cotton, 1983

Abstract

Abstract ‘Lockett 77’ was planted on 3 Jun at the Texas Agricultural Experiment Station, Chillicothe, Texas in Portales clay loam soil that had been treated with Treflan. Seeding rate was 17.9 kg/ha in excellent soil moisture. A side dressing of nitrogen at 56.0 kg/ha was applied on 8 Jul. Furrow irrigations were made on 28 Jul and 11 Aug. Six insecticide treatments were replicated 4 times in a randomized complete block design. Plots were 12 rows wide and 24.4 m long, and there was 102 cm between rows. Alleys separating replications were 7.6 m wide. Treatments were applied on 29 Aug with a John Deere 6000 Hi-Cycle ground sprayer with drop nozzles added which gave 3 Teejet TX12 nozzles per row. Ground speed was 4.9 km/h delivering 76.7 liters/ha total solution at 275 kPa. Rainfall from planting to end of sampling was 89.9 mm, 52.1 mm, 6.9 mm and 0.0 mm for Jun, Jul, Aug, and Sep, respectively. Beneficial insects were collected utilizing a standard insect sweep net with 50 sweeps being taken in each plot. Beneficials were bagged, taken to the laboratory and counted.