Herbicide Efficacy in Peanuts Grown Under Reduced Tillage Systems

Abstract

The use of reduced tillage systems in peanuts (Arachis hypogaea L.) from 1987 to 1989 resulted in weed problems, which in many instances required the use of a postemergence herbicide. When herbicides were applied prior to tillage, Pursuit (imazethapyr) tank-mixed with Roundup (glyphosate) or Gramoxone (paraquat) provided excellent control of southern crabgrass (Digitaria ciliaris Koel.) and Palmer amaranth (Amaranthus palmeri S. Wats.), while Texas panicum (Panicum texanum Buckl.) control was erratic. Under irrigated and rainfed conditions, a postemergence treatment of Poast, (sethoxydim) and Blazer (acifluorfen) provided the most consistent control of annual grasses and broadleaf weeds at six locations in South Texas. Prowl (pendimthalin) + Dual (metolachlor) provided the most consistent control (>85%) of annual grasses and yellow nutsedge (Cyperus esculents L.) when applied immediately before irrigation. When Prowl + Dual was applied 7 days prior to irrigation, annual grass control was reduced by 14 to 16%.