Adjuvant effects on CGA-248757 and flumiclorac efficacy and crop tolerance

Adjuvants influence weed control and crop tolerance provided by postemergen ce (POST) herbicides. Adjuvant effects on weed control and corn and soybean tolerance with CGA-248757 and flumiclorac applied alone and soybean tolera nce with CGA-248757 and flumiclorac applied in combination with imazethapyr or CGA-277476 were evaluated. Velvetleaf control in the greenhouse and com mon lambsquarters, redroot pigweed, and common ragweed control in the green house and field with CGA-248757 and flumiclorac were increased by the addit ion of an adjuvant. However, corn and soybean tolerance to these herbicides was not affected by adding an adjuvant. Laboratory studies suggest enhance d weed control from the addition of an adjuvant resulted from an increase i n CGA-248757 and flumiclorac foliar absorption. In greenhouse studies, velv etleaf, common lambsquarters, and redroot pigweed control with CGA-248757 p lus imazethapyr; velvetleaf control with flumiclorac plus imazethapyr; redr oot pigweed and common ragweed control with CGA-248757 plus CGA-277476; and velvetleaf, redroot pigweed, and common ragweed control with flumiclorac p lus CGA-277476 increased by adding an organosilicone adjuvant when compared with adding a nonionic surfactant (NIS). However, in field evaluations of CGA-248757 or flumiclorac plus imazethapyr, the addition of NIS or an organ osilicone adjuvant resulted in equivalent soybean injury, common lambsquart ers and redroot pigweed control, and soybean yield. Yet in tank mixtures of CGA-248757 or flumiclorac plus CGA-277476, the addition of an organosilico ne adjuvant increased redroot pigweed control and soybean yield compared to adding NIS.