Download or read book Weed Management Strategies in Conventional and Reduced tillage Cotton Production Systems written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Laboratory and greenhouse studies were conducted to determine the effect of temperature, solution pH, water stress, and planting depth on cutleaf eveningprimrose germination. Field studies were conducted to measure growth parameters of cutleaf eveningprimrose throughout the fall season. When treated with constant temperature, the optimum germination of cutleaf eveningprimrose occurred at 24 C. Onset, rate, and total germination were greatest in an alternating 20D 5 C temperature regime. Germination decreased as solution pH increased. Germination decreased when seed was subjected to increased water stress. Emergence was optimum when seed were buried at depths of 0.5 cm. Cutleaf eveningprimrose control was maximized when 2, 4-D was applied in mixture with glyphosate or paraquat. Five studies were conducted at Clayton, Rocky Mount, and Lewiston-Woodville, NC, in 2001 and 2002, to evaluate weed management, crop tolerance, and yield in strip- and conventional-tillage glyphosate-resistant cotton. The addition of S-metolachlor to either glyphosate formulation increased control of broadleaf signalgrass, goosegrass, large crabgrass, and yellow foxtail 14 to 43% compared to control with glyphosate alone. S-metolachlor was not beneficial for late season control of entireleaf morningglory, jimsonweed, pitted morningglory, or yellow nutsedge. The addition of S-metolachlor to either glyphosate formulation increased control of common lambsquarters, common ragweed, Palmer amaranth, smooth pigweed, and velvetleaf 6 to 46%. The addition of a late postemergence-directed spray (LAYBY) treatment of prometryn plus MSMA increased control to greater than 95% for all weed species regardless of early-postemergence (EPOST) treatment, and control was similar with or without S-metolachlor EPOST. Cotton lint yield was increased 220 kgD a with the addition of S-metolachlor to either glyphosate formulation compared to yield from glyphosate alone. Addition of the LAYBY increased yields.