Broadleaf Weed Control in Field Corn with Postemergence Herbicides

Abstract

A two-year study was conducted in 2002 and 2003 at the New Mexico State University Agricultural Science Center at Farmington, NM to evaluate postemergence herbicides for control of redroot and prostrate pigweed (Amaranthus retroflexus L. and Amaranthus blitoides S. Wats.), black nightshade (Solanum nigrum L.), common lambsquarters (Chenopodium album L.), and Russian thistle (Salsola iberica Sennen & Pau) and their effect on field corn (Zea mays) injury and yield. Herbicide treatments gave over 95% control of redroot and prostrate pigweed and common lambsquarters through August, in both years. Russian thistle control was 70% or less with DPX 79406, foramsulfuron, and nicosulfuron plus rimsulfuron when applied at 0.0115 plus 0.0115, 0.033, and 0.023 plus 0.012 lb a.i./acre, or in combination with mesotrione at 0.06 lb a.i./acre. Black nightshade control with foramsulfuron applied at 0.033 lb a.i./acre was 30 to 41% better than DPX 79406 or nicosulfuron plus rimsulfuron applied at 0.0115 plus 0.0115 and 0.023 plus 0.012 lb a.i./acre. This research indicates that when nicosulfuron plus rimsulfuron, DPX 79406, and foramsulfuron were applied in combination with diflufenzopyr plus dicamba, dicamba plus atrazine, mesotrione, or dicamba, broadleaf weed control increased significantly without field corn injury or yield reductions.