Investigating the Impacts of Airborne Dust on Herbicide Performance on Redroot Pigweed (Amaranthus retroflexus)

Abstract

Abstract Dust pollution poses environmental hazards, affecting agriculture through reduced sunlight exposure, photosynthesis, crop yields, and food security. Also, dust adversely impacts plant physiology and herbicide efficacy, but our study found it can also enhance certain herbicides. A factorial experiment was conducted in 2019 and replicated in 2020 to evaluate the interactive effects of dust and various herbicide applications, including bentazon, sulfosulfuron, tribenuron-methyl, aminopyralid + florasulam, foramsulfuron + iodosulfuron + thiencarbazone, 2,4-D + MCPA, and acetochlor on redroot pigweed (Amaranthus retroflexus L.) control efficacy. Dust decreased the total chlorophyll 9.2% content of redroot pigweed by 9.2%, while herbicide application reduced the redroot pigweed’s total chlorophyll by 67.5%. The reduction of total chlorophyll content was more pronounced when herbicides were applied in the presence of dust. Herbicides and dust reduced redroot pigweed's leaf, stem weights, and biomass. Finally, the total biomass of plants was reduced by tribenuron-methyl, aminopyralid + florasulam, sulfosulfuron, and foramsulfuron + iodosulfuron + thiencarbazone regardless of dust presence, showing the most significant effect. The study results indicate that herbicides used in the presence of dust could affect redroot pigweed growth, which signifies the presence of dust, resulting in decreased control efficacy or increased rate of herbicide resistance evolution.