Evaluation of Thrips Densities in At-Planting Seed and Soil Treatments on a Sharkey Clay Soil, 1997

Abstract

Abstract Plots were replicated four times in a RCB design and were four rows (40 inch centers) X 45 ft. ‘StoneviUe 474’ cotton seed was planted on a Sharkey clay soil on 5 May at the rate of 4 seed/row ft. Cotton seed was planted with a John Deere 7100 series planter which was equipped with 10-inch seed cones mounted to replace the seed hoppers. 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 (l/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. Control of thrips was assessed by randomly selecting 5 plants per plot at 7, 11, 16, 19, 23, 27, 31, and 35 days after emergence (DAE). Plant samples were washed to remove insects. Major past and/or secondary pest control was initiated in Jun and continued on an “as needed” basis through Aug. Percent open bolls was determined on 3 Sep. Samples of 25 bolls/plot were collected and ginned on a laboratory gin to determine lint percentage for each plot. These data were then used to determine lint yield. Plots were harvested on 19 Sep and 2 Oct. The center two rows were mechanically harvested using a John Deere spindle-type picker. Yields were con-verted to lb lint/acre.