植保无人机喷施不同雾滴粒径药剂对其在棉花冠层沉积、穿透及脱叶催熟效果的影响

Effect of spraying droplet size with drones on deposition, penetration, and cotton harvest-aid efficacy

中文关键词:植保无人机  雾滴粒径  雾滴沉积特征  棉花脱叶率  吐絮率

keywords:drone  droplet size  deposition characteristic  cotton defoliation  boll opening rat

中文摘要:为明确植保无人机喷施不同雾滴粒径药剂对其雾滴沉积、穿透以及棉花脱叶催熟效果，试验设置100、150、200和285 μm共4个不同雾滴粒径，用水敏纸测定雾滴在棉花冠层的沉积分布特征，并调查对棉花脱叶率和吐絮率的影响。结果表明，雾滴粒径对于沉积分布特征以及棉花脱叶率和吐絮率均有显著影响。当喷施雾滴粒径为100 μm时，具有最大的雾滴密度；当喷施雾滴粒径为150 μm和200 μm时，具有最大的覆盖度及沉积量；以下部沉积量与中部沉积量的比值为评价指标时，在喷施4个雾滴粒径下植保无飞机喷施雾滴的穿透率为39.4%~63.8%，各雾滴粒径之间差异不显著。在喷施4个雾滴粒径下，2018年和2019年棉花脱叶率分别为74.7%~80.4%和79.3%~88.4%；吐絮率分别为84.9%~92.0%和86.4%~94.2%。表明当喷施雾滴粒径为150 μm或200 μm，具有更高的脱叶率和吐絮率，较适宜棉田植保无人飞机脱叶催熟剂喷施选用。

Abstract:To clarify the effects of spray droplet size with drones on deposition, penetration, and cotton harvest-aid efficacy, four groups of droplet sizes (100, 150, 200, and 285 μm) were sprayed, and water-sensitive papers were used to measure the deposition characteristics in the cotton canopy. After application, cotton defoliation rate and boll opening rate were investigated. The results showed that droplet sizes had a significant effect on coverage, the number of droplets, and the amount of deposition, which further affected cotton harvest-aid efficacy. When 100 μm droplets were sprayed, the droplet density in the cotton canopy was the highest. When 150 μm and 200 μm droplets were sprayed, the coverage and deposition amount were largest. Droplet size had no significant effect on the penetration of droplets. The ratios of lower to middle canopy deposition amounts ranged from 39.4% to 63.8%. Under the four droplet sizes sprayed, the cotton defoliation rates were 74.7%-80.4% and 79.3%-88.4% in 2018 and 2019, respectively. The boll opening rates were 84.9%-92.0% and 86.4%-94.2%, respectively. When 150 μm or 200 μm droplets were sprayed, they had a better defoliation and boll opening rate, which is more suitable for drone application in the cotton field.