Effect of Aviation Spray Adjuvants on Defoliant Droplet Deposition and Cotton Defoliation Efficacy Sprayed by Unmanned Aerial Vehicles

Qinggang Xiao, Fang Xin, Zhaoxia Lou, Tingting Zhou, Guobin Wang, Xiaoqiang Han, Yubin Lan, Wei Fu
2019 Agronomy  
Defoliant spraying is an important aspect of mechanized cotton harvesting. Fully and uniformly spraying defoliant could improve the quality of defoliation and reduce the impurity content in cotton. Improving the coverage of defoliant droplets in the middle and lower layers of cotton and ensuring the full and even dispersion of droplets in the cotton canopy are essentially in increasing the defoliation effect. In this study, we assessed the effect of aviation spray adjuvants on droplet
more » ... n droplet deposition, defoliation, boll opening and defoliant retention in cotton leaves sprayed by an unmanned aerial vehicle (UAV). The results showed that adding aviation spray adjuvants could significantly improve the defoliant droplet deposition. Fifteen days after spraying, the defoliation rate was 80.31% and the boll opening was 90.61%. The defoliation rate increased by 3.12–34.62% and the boll opening rate increased by 6.67–29.56% after the addition of aviation spray adjuvants. Using a vegetable oil adjuvant could significantly increase the droplet coverage rate and the retention of defoliants in cotton leaves.
doi:10.3390/agronomy9050217 fatcat:tb7ew6mtcba4ddapbhghmi7i5i