Use of florpyrauxifen‐benzyl in non‐flooded rice production systems

摘要

Abstract The lack of a flood on rice (Oryza sativa) levees and in furrow‐irrigated rice creates a favorable environment for terrestrial weeds like Palmer amaranth (Amaranthus palmeri S. Wats) to emerge and quickly overtake the crop for a longer portion of the year than in flooded rice culture. Florpyrauxifen‐benzyl is a new auxin herbicide labeled for use in rice that has activity on both grasses and broadleaf weeds, as well as certain sedges. Field experiments were conducted to determine the efficacy of florpyrauxifen‐benzyl in a non‐flooded environment. Experiments were conducted in 2017 and 2018 at the Lon Mann Cotton Research Station in Marianna, AR and the Pine Tree Research Station near Colt, AR to evaluate florpyrauxifen‐benzyl within a herbicide‐based weed control program in furrow‐irrigated rice. Programs evaluated included two preemergence herbicide combinations, four mid‐postemergence combinations, and a late‐postemergence application versus none. Another experiment was conducted at the Pine Tree Research Station in 2017 and 2018 to compare florpyrauxifen‐benzyl with 2,4‐D in different herbicide mixtures for weed control on rice levees. Treatments consisted of several commonly used rice herbicides applied alone and in a mixture with florpyrauxifen‐benzyl and with 2,4‐D. In the furrow‐irrigated rice experiment, programs containing florpyrauxifen‐benzyl in the mid‐postemergence application resulted in higher levels of late‐season Palmer amaranth control (96–98%) compared to the standard mid‐postemergence treatment (85%). Additionally, programs that included a late‐postemergence herbicide application controlled Palmer amaranth (98%) compared to programs where no late‐postemergence herbicide was applied (91%). In the levee experiment, mixtures where florpyrauxifen‐benzyl was used offered comparable control of Palmer amaranth to mixtures containing 2,4‐D. Mixtures where 2,4‐D or florpyrauxifen‐benzyl were used controlled Palmer amaranth better than the individual herbicide applied alone. Results from these experiments indicate florpyrauxifen‐benzyl will sufficiently control Palmer amaranth in a non‐flooded environment, providing a good alternative herbicide and viable weed control option in furrow‐irrigated rice and on rice levees.