Zhao Rui, Sun Zhe, Bird Neal, Gu Yu-Cheng, Xu Yong, Zhang Zhen-Hua, Wu Xue-Min
Department of Applied Chemistry, College of Science, China Agricultural University, Beijing, China.
Syngenta Jealott's Hill International Research Centre, Bracknell, Berkshire, UK.
Pest Manag Sci. 2022 Apr;78(4):1582-1593. doi: 10.1002/ps.6777. Epub 2022 Jan 29.
Unmanned aerial vehicles (UAVs) have been developed to improve the efficiency of pesticide applications, and they are now widely utilized in Asia. The deposition and retention periods of pesticides on plant surfaces present serious challenges for modern precision agriculture, as these factors directly affect pesticide bioavailability, efficacy, and loss. Tank-mix adjuvants have been utilized to improve pesticide performance, but their effects on physicochemical properties and dosage delivery at low dilutions are not well understood.
We found that different tank-mix adjuvants affected droplet impact behavior, the wetting and spreading of spray dilutions, and pesticide deposition on rice leaves by changing the physicochemical properties of spray dilutions. The adjuvant methyl oxirane polymer with oxirane, mono (3,5,5-trimethylhexyl) ether (adjuvant c) significantly reduced the dynamic surface tension of the spray dilution and inhibited the rebound of large droplets (D = 2 ± 0.2 mm) and spray droplets (0.2 MPa with a LU-01 nozzle) on rice leaves, and improved the wetting and spreading performance of the spray dilution on rice leaves. Field tests showed that adjuvant c could significantly increase the deposition of chlorantraniliprole on rice leaves.
Overall, the use of appropriate tank-mix adjuvants at low dilution ratios for UAV application in paddy fields can improve the performance of spray dilutions, increase the effective deposition and wetting spread of pesticides on rice leaves, further reduce the dosage of pesticide products and improve pesticide utilization. © 2022 Society of Chemical Industry.
无人驾驶飞行器（UAV）已被开发用于提高农药施用效率，目前在亚洲广泛应用。农药在植物表面的沉积和滞留时间对现代精准农业构成严峻挑战，因为这些因素直接影响农药的生物利用度、功效和损失。桶混助剂已被用于提高农药性能，但其在低稀释度下对物理化学性质和剂量递送的影响尚不清楚。
我们发现，不同的桶混助剂通过改变喷雾稀释液的物理化学性质，影响液滴撞击行为、喷雾稀释液的润湿和铺展以及农药在水稻叶片上的沉积。助剂环氧乙烷与单（3,5,5-三甲基己基）醚的甲基环氧乙烷聚合物（助剂c）显著降低了喷雾稀释液的动态表面张力，抑制了大液滴（直径D = 2±0.2毫米）和喷雾液滴（使用LU-01喷嘴，压力0.2兆帕）在水稻叶片上的反弹，并改善了喷雾稀释液在水稻叶片上的润湿和铺展性能。田间试验表明，助剂c可显著增加氯虫苯甲酰胺在水稻叶片上的沉积量。
总体而言，在稻田无人机应用中以低稀释比例使用合适的桶混助剂可改善喷雾稀释液的性能，增加农药在水稻叶片上的有效沉积和润湿铺展，进一步降低农药产品用量并提高农药利用率。© 2022化学工业协会。
