SYNERGISM OF GRASS WEED-CONTROL WITH POSTEMERGENCE COMBINATIONS OF SAN-582 AND FLUAZIFOP-P, IMAZETHAPYR, OR SETHOXYDIM

Greenhouse and field experiments were conducted to evaluate early post emergence (POST) tank mixtures of SAN 582 with fluazifop-P, imazethapy r, or sethoxydim. In the greenhouse, SAN 582 synergistically improved barnyardgrass, broadleaf signalgrass, and johnsongrass control from im azethapyr and sethoxydim. Half-rates of imazethapyr and sethoxydim tan k-mixed with SAN 582 controlled grass weeds as well as full rates of e ither herbicide applied alone. Grass weed control with imazethapyr inc reased up to 40% with the addition of SAN 582. In field experiments, S AN 582 increased grass control with imazethapyr to a lesser degree tha n observed in the greenhouse. In a multispecies study, grass weed cont rol increased up to 15% when SAN 582 was tank-mixed with a reduced rat e of imazethapyr, although the full rate of imazethapyr applied POST w ith or without SAN 582 controlled grass weeds 80% or less. The combina tion of SAN 582 with sethoxydim was synergistic for barnyardgrass and johnsongrass control in this experiment. When applied POST in soybean, SAN 582 plus fluazifop-P or sethoxydim controlled barnyardgrass throu ghout the season better than a single POST application of a graminicid e.