Critical timing of weed removal in dry bean as influenced by the use of preemergence herbicides

Abstract

The critical timing of weed removal (CTWR) is the point in crop development when weed control must be initiated to prevent crop yield loss due to weed competition. A field study was conducted in 2018 and 2020 near Scottsbluff, NE to determine how the use of preemergence herbicides impacts the CTWR in dry bean. The experiment was arranged as a split-plot, with herbicide treatment and weed removal timing as main and sub plot factors, respectively. Herbicide treatment consisted of no-preemergence, or pendimethalin (1070 g ai ha–1) + dimethenamid-P (790 g ai ha–1) applied preemergence. Sub-plot treatments included season-long weed-free, weed removal at: V1, V3, V6, R2, and R5 dry bean growth stages, and a season-long weedy control. A four-parameter logistic model was used to estimate the impact of time of weed removal, for all response variables including dry bean yield, dry bean plants m–1 row, pods plant–1, seeds pod–1, and seed weight. The CTWR based on 5% yield reduction was estimated to range from the V1 growth stage [(16 d after emergence (DAE)] to the R1 growth stage (39 DAE) in the no-PRE herbicide treatment. In the PRE-applied treatment, the CTWR began at the R2 growth stage (47 DAE). Dry bean plants m–1 row was reduced in the no-preemergence treatment when weed removal was delayed beyond the R2 growth stage in the 2020 field season. The use of preemergence-applied herbicides prevented a reduction in the number of pods plant–1 in 2020, and the number of seeds pod–1 in 2018 and 2020. In 2018, the number of pods plant–1 was reduced by 73% when no-preemergence was applied, compared to 26% in the preemergence-applied treatment. The use of preemergence-applied soil active herbicides in dry bean delayed the CTWR and preserved yield potential.

Directions for improvement of the herbicide assortment in Russia at the beginning of the 21st century

“…As a rule, herbicide applications are recommended at the early stages of crop growth and development, or even before the seedlings' emergence because weeds at the early stages of their development are more susceptible to herbicides. Moreover, modern ideas concerning the planning of protective measures are based on the concept of critical timing of weed removal (CTWR) when treatments need to be applied to prevent yield decrease due to competition between the crop and weed plants (Nedeljković et al, 2021;Beiermann et al, 2022;Soltani et al, 2022). As a result, developmental stages have been established for each crop when they were routinely treated with herbicides.…”

Control of acetolactate synthase–resistant Palmer amaranth in dry edible bean

“…By comparison, a 50% yield loss would be expected in corn and soybean without effective weed control (Soltani et al 2016(Soltani et al , 2017a. Beiermann et al (2022b) found dry bean yield to be reduced by 82% to 97% in western Nebraska when weeds were allowed to compete with dry bean.…”

Effects of Weed Removal Practices on Soil Organic Carbon in Apple Orchards Fields

“…Soil organic carbon (SOC) includes plants, roots, fungi, and microbial residues and accounts for more than 60% of global total soil carbon [1]. The understanding of weed-removal practices, including herbicides application and mulching, which affect soil carbon balance dynamics, is crucial for yield-potential preservation, terrestrial ecosystem conservation, and food security [2,3]. Sustainable weed management constitutes a challenge for ensuring agricultural productivity since in the case of improper management, infestations of grass and broadleaf weeds could reduce crops yield and quality.…”