Control of Thrips in Cotton with In-Furrow Insecticides, 1990

Abstract

Abstract Cotton was planted on 29 May at the University of Arkansas Northeast Research and Extension Center in Keiser, AR. Granular in-furrow treatments were applied with a Gandy box on the planter while in-furrow spray treatments were applied with a CO2 powered sprayer on the planter. The sprayer was calibrated to deliver 11 gal/acre at 20 psi through 8203 flat fan nozzles directed into the furrow in front of the press wheel. Liquid sidedress treatments were applied using a CO2 powered backpack sprayer equipped with 1 8203 flat fan nozzle/row delivering 11 gal/acre at 20 psi. Granular sidedress treatments were applied with a coffee can with a small hole in the bottom and calibrated to deliver the desired rate. All sidedress treatments were directed to the ground next to a row and cultivated in immediately following application. Plots were 4, 38-inch rows, 50 ft long arranged in a RCB design with 4 replications. Ratings were made on 12, 20, and 27 Jun and 13 Jul. Visual damage ratings were made on a scale of 1-10 with 10 = severe damage. Thrips were counted by removing 5 plants per plot and washing the plants through a series of sieves, counting the thrips trapped by the last sieve. Plant height and node measurements were also made. Plots were harvested on 17 Oct for first pick and 27 Oct for second pick by harvesting the center 2 rows in each plot.