Impact of Cover Crop and At-Planting Insecticide on Thrips Populations, 1996

Abstract

Abstract Plots were replicated four times in a split plot design and were four rows (40 inch spacing) X45 ft. Stoneville 474 cotton seed of the same seed lot was planted on 7 May on a Sharkey clay soil which was fertilized with 90 lb N/acre. Cotton seed was planted no-till with a John Deere 7100 series planter which was equipped with 10 inch-seed cones mounted to replace the seed hoppers. The seeding rate was 4 seed/row ft. Granular in-furrow treatments were applied with 8-inch belt cone applicators mounted to replace the standard granular applicators. In-furrow spray treatments were applied with a CO2 charged spray system through 25015 nozzles (1/row) mounted in front of the press wheels. The spray tips were turned to spray across the furrow and calibrated to deliver 5 gpa finished spray. Cover crop treatments consisted of winter wheat and native winter vegetation. Control of thrips was assessed by randomly selecting 5 plants per plot on 21 and 28 May and 7 Jun. Plant samples were processed by using whole-plant washing procedures to remove insects. Major pest and/or secondary pest control was initiated in Jun and continued on an “as needed” basis through Aug