THE COMPETETIVENESS OF COTTON CULTIVARS AGAINST DP 555 B/R WHEN DOUBLE-CROPPED BEHIND WINTER WHEAT
Harris*, H.M.1; Tyson, C.T.21Worth County Extension Coordinator, University of Georgia Cooperative Extension, 204 E. Franklin St., #9, Sylvester, GA, 31791
2Worth County Extension Agent, University of Georgia Cooperative Extensions, 204 E. Franklin St., #9, Sylvester, GA, 31791
Abstract:
The introduction of the cotton variety DP 555 B/R brought with it dramatic improvements in cotton lint yield for farms in Southwest Georgia. The variety contains multiple characteristics which provide a significant yield advantage over competing cotton germplasm. Field studies were conducted in 2008 and 2009 to evaluate the competitiveness of other varieties to DP 555 B/R when planted later than the recommended optimum timing. Competitive varieties from multiple cottonseed companies, as well as DP 555 B/R were compared by planting into burned wheat stubble in 2008, and cut wheat chaff in 2009. The field was watered using center pivot irrigation. Planting rate, weed control, insect control, and defoliation timing were applied equally and consistently with respect to treatment and timing across all varieties. Plots were harvested November 20, 2008, and December 18, 2009 using conventional spindle harvesting methods, and plot weights taken using a boll-buggy outfitted with electronic scales. Means of yield were taken, and differences were observed with respect to different varieties. Results of this study show that suitable replacement varieties exist to compete with DP 555 B/R after its removal from the marketplace in 2010. Newly released varieties have been shown to outyield DP 555 B/R by more than 100 pounds of lint per acre