Field experiments were conducted from 2009 through 2011 to evaluate peanut tolerance to postemergence (POST) applications of pyroxasulfone applied alone or in combination with commonly used foliar herbicides. Hherbicide treatments were arranged in a factorial arrangement that included three pyroxasulfone rates (0, 240, and 480 g ai/ha) and four POST application timings [10, 30, 60, and 90 days after planting (DAP)]. Pyroxasulfone applied at 240 or 480 g ai/ha 10 DAP caused 24 and 33% stunting 2 weeks after treatment (WAT), respectively. Regardless of pyroxasulfone rate, peanut stunting following application 30, 60, or 90 DAP was less than 3%. Peanut yield was not influenced by POST applied pyroxasulfone applied alone. In a second experiment, herbicide treatments were applied in a factorial treatment arrangement that included two pyroxasulfone rates (0 and 240 g ai/ha) and six POST herbicide systems [none; paraquat (140 g ai/ha); paraquat (210 g ai/ha) plus bentazon (280 g ai/ha); paraquat (210 g ai/ha) plus bentazon (560 g ai/ha) plus acifluorfen (280 g ai/ha); imazapic (70 g ai/ha); and lactofen (220 g ai/ha)]. Stunting 2 WAT with paraquat applied 10 DAP ranged from 33 to 37% while less injury was observed with lactofen or imazapic. Peanut stunting 9 WAT ranged from 3 to 6% regardless of weed management system. Pyroxasulfone applied in combination with POST herbicides did not reduce peanut yield.
Read full abstract