Quantifying the detrimental effect of airborne dust on herbicide efficacy

Abstract

AbstractOne side effect of human activity and global climatic change is more airborne dust. This not only has undesirable effects on human health and the environment, but may also adversely affect many agricultural processes, including herbicide efficacy. This is particularly relevant in parts of the world where dust storms are common and limited rainfall means dust persists on plants for protracted periods. Accordingly, a series of greenhouse dose–response pot experiments was carried out to quantify the effect of a dust concentration of 1,500 µg/m3 on the performance of paraquat, glyphosate, sulfosulfuron and 2,4‐D+MCPA. Dust‐treated and untreated seedlings of Hordeum spontaneum and Sinapis arvensis were sprayed with sulfosulfuron and 2,4‐D+MCPA, respectively, while paraquat and glyphosate were applied to both weed species. The efficacy of glyphosate and paraquat decreased significantly in the presence of dust on both species. Similar results were observed for 2,4‐D+MCPA on S. arvensis. In contrast, the efficacy of sulfosulfuron on H. spontaneum was not affected by dust. In the presence of dust, the doses of glyphosate, paraquat and 2,4‐D+MCPA required for a 90% effect were enhanced by a factor of 1.9 to 2.6. The negative impact on glyphosate efficacy was more pronounced in S. arvensis than H. spontaneum, while it was similar for paraquat. Future studies should consider the amount, duration and composition of dust as well as its impact on other weeds and herbicides. Potential approaches to overcome the detrimental influence of dust on the performance of herbicides were also suggested for future studies.