Recurrent herbicide applications on wheat: impact on productivity, weed dynamics, and nutrient depletion

Abstract

Wheat fields with weeds are known to contribute significantly to nutrient depletion, which lowers grain yield and quality. Given the unpredictable affects of these intricate and dynamic mixes, the use of herbicide combos and successive applications poses challenges to current standards aimed at maintaining ecosystem health. Thus, a two-year field experiment was carried out with a focus on soil health in a mesocosm experiment to identify the best herbicides to control weeds and assess the phytotoxic effects of herbicide mixtures while adhering to a feasible application timeline for wheat production. In a randomized block design with four replications, this study includes nine treatments. Plots treated with pendimethalin 30% EC at 1.0 kg/ha and metribuzin 70% WP at 0.2 kg/ha demonstrated significantly reduced weed uptake of potassium (K), phosphorus (P), and nitrogen (N). This finding was statistically identical to plots treated with sulfosulfuron 75% + metsulfuron 5% WG at 32 g/ha and pendimethalin 30% EC at 1.0 kg/ha, resulting in manual weeding at 30 days after sowing (DAS). In addition, pendimethalin and metribuzin prove effective to control weeds, yet they exhibited great efficacy in increasing wheat grain and straw yields. Treatments with pendimethalin, metribuzin, and sulfosulfuron + metsulfuron revealed substantial increases in the concentrations of N, P, and K in wheat grains. As a result, wheat growers need to exercise caution whenever it comes to the phytotoxic effects and environmental ramifications of herbicides. As consequently, sulfosulfuron 75% + metsulfu-ron 5% WG at 32g/ha proved to be an effective and environmentally friendly choice that boosted both productivity and quality.