Response of dry beans to tiafenacil applied preemergence

Abstract

Tiafenacil is a new non-selective, protoporphyrinogen IX oxidase (PPO) – inhibiting pyrimidinedione herbicide that is under consideration for registration in corn, soybean, wheat, cotton, and other crops to control grass and broadleaf weeds prior to crop emergence. The sensitivity of dry beans to tiafenacil is not known. Four field experiments were completed at Exeter and Ridgetown, ON, Canada during the 2019 and 2020 growing seasons to determine the sensitivity of azuki, kidney, small red, and white beans to tiafenacil applied preemergence (PRE) at 12.5, 25, 50, and 100 g ai ha−1. Tiafenacil at 100 g ai ha−1 caused 5% or less injury to azuki, kidney, small red and white beans, and 0 to 3% injury in azuki bean, 1-5% injury in kidney bean, 1-4% injury in small red bean, and 1 to 4% injury in white bean. Tiafenacil applied PRE at 12.5, 25, 50, and 100 g ai ha−1 caused up to 1, 4, 4, and 5% visible dry bean injury, respectively but caused no negative effect on other growth parameters measured including the final seed yield. Crop injury was generally the greatest with tiafenacil at the 100 g ai ha−1 in dry beans. Generally, kidney, small red, and white bean were more sensitive to tiafenacil than azuki bean. Dry bean injury was persistent and increased with time with the greatest injury observed 8 WAE. Tiafenacil applied PRE can be a useful addition to the current weed control strategies for grass and broadleaf weed control suppression, especially GR horseweed and amaranth species prior to bean emergence.

Tolerance of White Bean to Tiafenacil Herbicide Mixtures and Control of Multiple Herbicide-Resistant Horseweed With Tiafenacil Herbicide Mixtures

“…Results are similar to other studies in which tiafenacil applied PRE at 25 g a.i. per ha -1 caused 0-4% injury in azuki, kidney, small red, and white bean and caused no adverse effect on plant stand, dry biomass, height, SM content, and yield (Soltani et al, 2021b). Sprague et al (2020) also observed no visible injury, plant stand reduction, or yield reduction with tiafenacil applied PP at 24 g a.i.…”

“…Control of weeds, especially MHR horseweed has not been consistent with the co-application of glyphosate (C 3 H 8 NO 5 P) + tiafenacil (Soltani et al, 2021b;Westerveld, 2021;Westerveld et al, 2021). Earlier studies have shown that glyphosate + tiafenacil applied PP provides only 51-68% control of MHR horseweed in soybean (Soltani et al, 2021b). The co-application of glyphosate + tiafenacil with bromoxynil (C 7 H 3 Br 2 NO), metribuzin (C 8 H 14 N 4 OS), halauxifen-methyl (C 14 H 11 C l2 FN 2 O 3 ), 2,4-D ester, bromoxynil + metribuzin, bromoxynil + halauxifen-methyl, or bromoxynil + 2,4-D ester applied PP may improve MHR horseweed control.…”

“…per ha -1 ) applied PP caused no visible black bean injury and no reduction in stand or yield. Control of weeds, especially MHR horseweed has not been consistent with the co-application of glyphosate (C 3 H 8 NO 5 P) + tiafenacil (Soltani et al, 2021b;Westerveld, 2021;Westerveld et al, 2021). Earlier studies have shown that glyphosate + tiafenacil applied PP provides only 51-68% control of MHR horseweed in soybean (Soltani et al, 2021b).…”

“…Earlier research has shown that tiafenacil (25 g a.i. per ha -1 ) applied PRE causes minimal (0-4%) injury in azuki, kidney, small red, and white bean and caused no adverse effect on plant stand, dry biomass, height, maturity (as measured by SM content), and yield (Soltani et al, 2021b). Sprague et al (2020) reported that tiafenacil (24 g a.i.…”