GLYPHOSATE TANK MIXTURES WITH SAN-582 FOR BURNDOWN OR POSTEMERGENCE APPLICATIONS IN GLYPHOSATE-TOLERANT SOYBEAN (GLYCINE-MAX)

Field experiments were conducted to evaluate postemergence (POST)-appl ied tank mixtures of 560, 1,120, and 1,680 g ai/ha glyphosate with or without 1,120 g ai/ha SAN 582 (proposed name, dimethenamid) as burndow n treatments or POST in glyphosate-tolerant soybean. SAN 582 was not a ntagonistic with glyphosate at the glyphosate rates evaluated. In the burndown study, glyphosate controlled horseweed 98% or more and curly dock 82% or more with or without SAN 582. However, broadleaf signalgra ss emerged after the burndown treatments were applied. All tank mixtur es that included SAN 582 controlled broadleaf signalgrass 84 to 96%, 6 wk after treatment. In the glyphosate-tolerant soybean study, glyphos ate controlled barnyardgrass and johnsongrass present at the time of a pplication 89% or more, regardless of rate. Tank mixtures of SAN 582 w ith glyphosate controlled late-season flushes of barnyardgrass through residual activity of the SAN 582. Applying SAN 582 with glyphosate im proved soybean yield 500 kg/ha over glyphosate applied alone.