| A two year experiment was conducted in the Mississippi Delta in 2011 and 2012 to determine the most efficacious rates and timings for the preemergence and postemergence control of glyphosate-resistant (GR) Palmer amaranth with dicamba. In addition, a greenhouse experiment was conducted to confirm the optimum rate for control of Palmer amaranth with a new formulation of dicamba (BAS 18322H). Preemergence field experiments included dicamba at 0, 0.28, 0.56, and 1.1 kg ae ha-1 and were compared to 0.07 kg ae ha-1 flumioxazin. These treatments were applied at 30, 15, and 0 days prior to planting. Postemergence field experiments included dicamba at 0.28, 0.56, and 1.1 kg ae ha-1 applied with and without 0.84 kg ae ha-1 glyphosate to 5, 10, and 15 cm Palmer amaranth. In the greenhouse, dicamba at 0.14, 0.28, 0.56, 1.1, and 2.2 kg ha-1 was applied to 5, 10, and 15 cm Palmer amaranth. |
