Weed control in conventional soybean with pendimethalin followed by imazethapyr plus imazamox/quizalofop

The objectives of this study were to evaluate the efficacy of pendimethalin applied pre-emergence (PRE) followed by (fb) post-emergence (POST) application of imazethapyr plus imazamox/quizalofop for weed control and their effect on conventional soybean injury, yield attributes, and yield. Field experiments were conducted in 2013 and 2014 in conventional soybean. Herbicide treatments provided ≥ 90, 70, and 85% control of crowfoot grass, large crabgrass, and goosegrass, respectively, and ≤ 80% control of false amaranth and horse purslane at 30 d after sowing (DAS). At 60 DAS, pendimethalin applied alone or fb hand-hoeing/quizalofop/imazethapyr plus imazamox provided 100% control of goosegrass and 65 to 100% control of crowfoot grass/large crabgrass. Pendimethalin fb imazethapyr plus imazamox/quizalofop as well as quizalofop applied alone resulted in complete control of crowfoot grass, large crabgrass, and goosegrass, but control of broadleaf weeds was variable. Pendimethalin fb imazethapyr plus imazamox at 70 g ha─1 at 28 DAS, imazethapyr plus imazamox at 60 or 70 g ha─1 at 21 DAS fb quizalofop at 37.5 g ha─1 at 42 DAS resulted in soybean branch numbers per plant, number of pods per plant, and soybean seed yield comparable to weed-free control. Control of Benghal dayflower and purple nutsedge was not acceptable.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author