提升水稻上植保无人机喷施药液沉积效果的关键因素OACSTPCD

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.