Impact of tank-mix adjuvants on deposit formation, cuticular penetration and rain-induced removal of chlorantraniliprole

作者：Adriano Arrué Melo, Jaime Usano‐Alemany, Jerson Vanderlei Carús Guedes, Maurício Hunsche · 发表于：Crop Protection · 年份：2015 · DOI：10.1016/j.cropro.2015.09.021 · 被引用次数：34 · 研究领域：Plant Surface Properties and Treatments、Insect and Pesticide Research、Pesticide Residue Analysis and Safety

Off-target deposits of agrochemicals impose a general risk for the environment while environmental factors such as rainfall might cause significant pesticide removal from agricultural crops and contribute to a requirement for a higher rate and frequency of applications in intensive agricultural systems. In the present study, we analyzed the impact of five tank-mix adjuvants (three organosilicones – one superspreader, one penetrating agent and one spreader-sticker – as well as one paraffinic oil and one vegetable oil with non-ionic surfactants) on the amount of active ingredient (AI) deposited, deposit characteristics at the microscale, and rain-induced removal of chlorantraniliprole from the hydrophobic leaf surfaces of wheat and maize. In addition, the cuticular penetration of the AI was determined on astomatous cuticles from the adaxial side of apple leaves. The tank-mix adjuvants with lower surface tension (organosilicone superspreader and organosilicone-based penetrating agent) caused a lower contact angle of sessile droplets, larger surface coverage, and higher AI amount on wheat and maize leaves. Heavy rain (5 mm h −1 ) removed zero to 60% of the chlorantraniliprole from wheat leaves, and 20–60% from maize leaves, the losses being more pronounced in those treatments with higher initial AI amount. Moreover, in wheat we observed a pronounced effect of the rain amount (5 mm or 10 mm) on the AI removal. Environmental scanning electron micrographs indicated the rain-induced ...