提升水稻上植保无人机喷施药液沉积效果的关键因素

Key Factors for Improving Deposition Effects of Pesticide Mixture Sprayed by Plant Protection UAV on Rice

旨在解决植保无人机在水稻上施药后存在雾滴分布不均、农药沉积率不高等实际田间作业问题,比较分析了飞防助剂、施药液量、飞行速度对植保无人机在水稻上施药后雾滴分布和农药沉积率的影响,明确可产生显著性差异的关键因素,进一步分析该因素是否影响农药混配药液的微粒物理性质和润湿性能。结果表明:在三因素三水平的正交试验中,不同试验处理在上层收集的雾滴的面积显著大于中层和下层,加入助剂促使试验处理在不同高度上的雾滴分布较为均匀,它们在中、下层收集的雾滴的面积占比明显得到提高;飞防助剂、施药液量和飞行速度可不同程度地影响农药沉积率,农药沉积率范围在43.72%~68.63%;体现3个因素对农药沉积率影响程度的R值分别为13.44、6.25和4.93,其中仅飞防助剂产生的差异达显著性水平;在药液混配后0~48 h内,加入2种不同助剂均可显著降低其表面张力和静态接触角,加入2种不同助剂的药液之间则未表现显著差异;此外,呈现较高农药沉积率的助剂品种则可同时有效降低药液在混配后0~48 h内的粒径大小和粒径分散程度。研究结果对于植保无人机在水稻上的精准施药技术提升具有重要参考依据,可以提高农药沉积率,减少农药流失。

This study intended to solve the field operation issues of plant protection UAV exiting in the pesticide application on rice,such as poor uniformity of droplet distribution and low pesticide deposition rates.In this study,we evaluated the influence of different factors on the droplet distribution and pesticide deposition rates after UAV application,such as pesticide adjuvant,application volumes,and flight speeds.Key factors that produced significant differences among different treatments were identified,and their effects on the particle physical properties and wettability of the pesticide mixture were further analyzed.Among the orthogonal tests based on three factors and three levels,areas of droplets collected at the upper layer were significantly higher than both of middle and lower layers,addition of pesticide adjuvant could increase the uniform of droplets distributed at different heights,and the area proportion of droplets collected at middle and lower layers were significantly increased in comparison with the treatments without adjuvant.The pesticide adjuvant,application volumes,and flight speeds were found to affect the pesticide deposition rates to varying degrees,pesticide deposition rates ranged from 43.72%to 68.63%;R values reflecting the influence of three various factors on the pesticide deposition rates were 13.44,6.25 and 4.93,respectively,and only the difference caused by pesticide adjuvant could reach significant level.After preparation of 0-48 h,addition of two kinds of pesticide adjuvant both significantly reduced the surface tensions and static contact angles of pesticide mixtures,while there was not significant difference between the mixtures prepared with different kinds of adjuvant.Moreover,the variety of pesticide adjuvant that showed higher pesticide deposition rates could also effectively reduce the particle sizes and the dispersion of particle size of pesticide mixture within preparation of 0-48 h.Thus,our research provides an important reference for the improvement of precise pesticide application of UAV on rice,and helps improve the pesticide deposition rates and reduce the loss of pesticides.