Seasonwide Weed Management Utilizes Florpyrauxifen-Benzyl in Water-Seeded Rice Production Systems

Florpyrauxifen-benzyl (FPB) is an auxin-mimic herbicide that controls selected grasses, sedges, and broadleaves in rice cropping systems. Field experiments were conducted in 2023 and 2024 to characterize the effects of FPB on crop safety and weed control when applied alone or in combination with other herbicides, and to assess whether FPB can provide season-long, effective weed management. Base treatments of benzobicyclon (BBC)/halosulfuron-methyl (HSM), clomazone (CLM), or thiobencarb (TBC) were applied on the day of seeding (DOS) or within the 2-leaf stage (LS) rice and followed by foliar treatments of FPB alone or in a mixture with bispyribac-sodium (BPS), penoxsulam (PNX)/cyhalofop-butyl (CHB), or propanil (PPL). Additionally, FPB was applied alone with no prior base treatment, in combination with a mixture partner, and as a sequential treatment, 14 days apart, with the first application made to 4- to 5-LS rice; in contrast, the second application was made to mid-tillering rice. The FPB applied alone or in sequential application showed results for more than 98% of watergrasses and 100% of ricefield bulrush, smallflower umbrella sedge, ducksalad, redstems, and all other broadleaves control at 56 days after treatment (DAT). When applied after the base treatments, the weed control increased to 100% for all weed species at 14 DAT. The sequential application of FPB achieved the highest yields of 7683 kg ha−1 in 2023 and 11,249 kg ha−1 in 2024, resulting in 3.6- and 6.4-fold increases in rice yield over the nontreated control. Owing to its excellent sedge and broadleaf weed control and good activity on troublesome grasses, such as barnyardgrass, FPB could be an essential part of the weed management programs in rice production systems.