Larbi Peter A, Culumber Mae, Thistle Harold W, Willett Michael J
Kearney Agricultural Research and Extension Center, University of California Agriculture and Natural Resources, Parlier, CA, USA.
Department of Biological and Agricultural Engineering, University of California-Davis, Davis, CA, USA.
Pest Manag Sci. 2025 Jul;81(7):3811-3821. doi: 10.1002/ps.8747. Epub 2025 Mar 27.
Off-target drift of pesticides from orchard airblast spray applications has potential implications for human health and the environment. A field study was conducted in a commercial almond orchard to generate spray drift data for validating a mechanistic airblast spray drift risk assessment model under development. Pyranine fluorescent dye solution spray was applied in 22 trials at 935.4 L/ha with the sprayer making four passes along the third drive lane upwind from the edge of orchard. Drift was measured with artificial spray samplers distributed in an adjacent open field up to 183 m from the edge of the orchard, which were retrieved and analyzed by fluorometry to generate dye drift deposition data.
Drift data showed downwind deposit decay, indicating the extent of drift under different prevailing weather conditions. Terminal drift amount (in percentage of applied dose) and distances were estimated to be: 6.0 × 10 at 531.1 m for artificial foliage; and 4.0 × 10 at 232.8 m for horizontal string. Weather condition caused variation in drift among spray trials but only wind direction, wind speed, and atmospheric pressure were significant in accounting for the variability.
This new dataset provides opportunities for objective pesticide risk assessment decision-making that will potentially impact regulations affecting the California almond industry. The data will also be useful for confirming and/or updating spray application best practices for promoting efficiency, effectiveness, and environmental sustainability. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
果园气力喷雾施用农药时产生的非靶标漂移对人类健康和环境具有潜在影响。在一个商业化杏仁果园开展了一项田间研究，以生成喷雾漂移数据，用于验证正在开发的一种机械气力喷雾漂移风险评估模型。在22次试验中，以935.4升/公顷的用量喷施了吡喃荧光染料溶液，喷雾器沿着果园边缘上风方向的第三条车道行进四次。利用分布在距果园边缘最远达183米的相邻开阔田地里的人工喷雾采样器测量漂移情况，采集后通过荧光测定法进行分析，以生成染料漂移沉积数据。
漂移数据显示了顺风沉积衰减情况，表明了不同盛行天气条件下的漂移程度。估计人工树叶在531.1米处的终端漂移量（占施用量的百分比）和距离为6.0×10；水平细绳在232.8米处为4.0×10。天气状况导致各喷雾试验中的漂移存在差异，但仅风向、风速和大气压力对这种变异性具有显著影响。
这个新数据集为客观的农药风险评估决策提供了机会，这可能会影响到适用于加利福尼亚杏仁产业的法规。这些数据对于确认和/或更新喷雾施用的最佳实践以提高效率、效果和环境可持续性也将是有用的。© 2025作者。《害虫管理科学》由约翰·威利父子有限公司代表化学工业协会出版。
