Abstract
Field and greenhouse experiments evaluated purple nutsedge (Cyperus rotundas L.) and yellow nutsedge (C. esculentus L.) control with mixtures of bentazon [3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] and imazethapyr {2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3-pyridinecarboxylic acid} applied postemergence. Mixtures of the sodium salt of bentazon at 0.6 or 1.1 kg ae/ha and the ammonium salt of imazethapyr at 35 or 70 g ae/ha were antagonistic on purple nutsedge in field and greenhouse experiments. Mixtures of bentazon at 0.6 kg/ha and imazethapyr at 35 or 70 g/ha were additive on yellow nutsedge in field experiments but antagonistic in greenhouse experiments. Mixtures of bentazon at 1.1 kg/ha and imazethapyr at 35 or 70 g/ha were antagonistic on yellow nutsedge in field and greenhouse experiments.