TITLE:
Responses of Dry Bean to 2,4-D Ester Applied Preplant and Preemergence
AUTHORS:
Nader Soltani, Christy Shropshire, Peter H. Sikkema
KEYWORDS:
Bean Stand, Crop Injury, Dry Bean Biomass, Plant Height, Plant Sensitivity, Yield
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.10 No.12,
December
12,
2019
ABSTRACT: Six field studies were completed in Ontario (during
2016 to 2018) to assess the tolerance of adzuki, kidney, small red and navy
bean to 2,4-D ester at 528 or 1056 g·ai·ha-1 applied 14, 7 and 1 day before
seeding (PP) and 3 days after seeding (PRE). 2,4-D applied PP or PRE caused
as much as 4%, 6%, 7% and 8% injury in adzuki, kidney, small red and navy
(white) bean, respectively. There was an increase in bean injury as the preplant interval decreased. At 1 WAE, 2,4-D
applied at 1056 g·ai·ha-1 14, 7 and 1 day PP and 3 days after
seeding caused up to 6%, 10%, 18% and 5% visible bean injury, respectively. The
level of injury decreased over time with minimal bean injury (0 to 3%) at 8
WAE. Bean stand counts were similar
to the non-treated control with 2,4-D applied at various timings except at 1 day
PP when 2,4-D at the 2X rate decreased bean stand 13%. There was up to 23% and
43% decrease in bean dry weight with 2,4-D applied PP at 528 and 1056 g·ai·ha-1 7 and 1 day PP, respectively. Bean height (6 WAE) was not affected by 2,4-D
applied at various timings except at 1 day PP when 2,4-D (1056 g·ai·ha-1)
decreased bean height 10%. Additionally, there was no effect of 2,4-D
treatments on bean maturity or yield. Based on these results, the safest times
to apply 2,4-D are 14 days before seeding or PRE. Injury was higher when 2,4-D was applied 7 and 1 day PP. Injury was lower in adzuki bean compared to kidney, small red or navy bean.