Potential risk of drift from inclined fan nozzles

ABSTRACT Pest, disease and weed control in large-scale crops depend on the application of agrochemicals. These applications are subject to several factors that can lead to drift. The objective of this study was to evaluate the effect of spray nozzles with inclined flat jet, on the drift. The drift was collected in a 10 m wind tunnel, with a spray system inside. The samples were collected in 5 horizontal points, from 2.0 to 6.0 m away from the spray nozzle and 5 points in the vertical, from 0.1 to 0.5 m away from the lower base of the wind tunnel, totaling 25 sample points. The mixture applied was glyphosate (isopropylamine salt, 1080 g a.e. ha-1) with 2,4-D (dimethylamine salt, 1.005 g a.e. ha-1). The nozzles J3D 100 025, JGC 120 02, JAP 110 015 and ADI 110 015 (control), inclined by 37.5º, 20º, 15º and 0º, respectively, were used in two directions of spray: upwind and downwind of the air flow direction. The nozzles J3D, JGC and JAP, when inclined downwind reduced the drift by 16.1, 2.6 and 39.0%, respectively, relative to the control, and when inclined upwind, reduced drift by 53.4, 3.9 and 18.6%, respectively, relative to the control. Spray nozzles with second-generation air-induction inclined flat jet (JAP) and standard inclined flat jet (J3D) reduce the collected drift compared to the nozzle without inclination, regardless of wind flow direction.

摘要 大规模作物病虫草害防控依赖农用化学品的施用，此类施药过程受多种因素影响，易引发农药飘移（drift）。本研究旨在评估倾斜扁平射流喷头对农药飘移的影响。实验于10米风洞内开展，风洞内部搭载施药系统以采集药剂飘移样本。采样设置为：距喷头2.0至6.0米范围内设置5个水平采样点，距风洞下底面0.1至0.5米范围内设置5个垂直采样点，总计25个采样点位。供试药剂为草甘膦（异丙胺盐，1080 g a.e. ha⁻¹）与2,4-滴（二甲胺盐，1.005 g a.e. ha⁻¹）的复配制剂。所用喷头包括J3D 100 025、JGC 120 02、JAP 110 015及ADI 110 015（对照组），其倾斜角度分别为37.5°、20°、15°与0°，且分别沿气流逆风侧与顺风侧两个方向施药。相较于对照组，J3D、JGC与JAP喷头在顺风倾斜施药时，农药飘移量分别降低16.1%、2.6%与39.0%；在逆风倾斜施药时，飘移量分别降低53.4%、3.9%与18.6%。无论气流方向如何，第二代空气诱导型倾斜扁平射流喷头（JAP）与标准倾斜扁平射流喷头（J3D）的药剂飘移收集量均低于无倾斜喷头。