Response of Navy Bean (Phaseolus vulgaris) and Wheat (Triticum aestivum) Grown in Rotation to Clomazone, Imazethapyr, Bentazon, and Acifluorften

The response of ‘C-20’ navy bean and ‘Frankenmuth’ soft white winter wheat grown in rotation to clomazone, imazethapyr, bentazon, and acifluorfen was examined. Clomazone at 560 and 430 g ai ha−1plus 800 g ai ha−1pendimethalin and 2000 g ai ha−1chloramben visibly injured navy bean in 1 of 2 yr. However, navy bean seed moisture at harvest and yield was not reduced compared to the weed-free control. PPI and PRE treatments of 70 g ai ha−1imazethapyr did not injure navy bean or reduce yield. Imazethapyr applied POST at 70 g ha−1plus nonionic surfactant visibly injured navy bean. The addition of urea ammonium nitrate to imazethapyr enhanced visible injury and seed moisture compared to nonionic surfactant alone in 1 of 2 yr. However, seed yield was not reduced. Seed moisture at harvest was greater following treatment with 430 g ai ha−1acifluorfen plus nonionic surfactant or urea ammonium nitrate and 140 and 280 g ha−1acifluorfen plus 840 g ai ha−1bentazon in 1 of 2 yr compared to the weed-free control, but yield was not reduced. Wheat yield was reduced in 2 of 2 and 1 of 2 yr by 560 g ha−1and 430 g ha−1clomazone, respectively, plus pendimethalin plus chloramben compared to the weed-free control. Wheat yield was not reduced by imazethapyr, bentazon, or acifluorfen.