植保无人机水稻田间农药喷施的作业效果

【目的】测试和对比电动单旋翼与电动多旋翼植保无人机在水稻田间的作业效果。【方法】测试的植保无人机为HY-B-15L型单旋翼植保无人机(单旋翼机)和MG-1S型多旋翼植保无人机(多旋翼机)。以一定比例的罗丹明B与善思纳米农药的混合溶液作为喷施溶液,通过改变无人机作业高度和农药喷洒量进行田间喷施试验,采用荧光示踪剂法和水敏纸图像分析法获得2种无人机在不同喷施条件下喷施的雾滴在靶标上的沉积效果。按田间药效调查准则,调查不同处理下的纳米农药对水稻病虫害的防治效果。【结果】2种无人机喷施的雾滴在各采样点上的沉积量随农药喷洒量的增加而增加,当农药喷洒量为66.67和100.00 mL·hm~(–2)时,单旋翼机在各采样点上的沉积量比喷洒量为46.67 mL·hm~(–2)时的分别增加了48.50%和137.73%,多旋翼机分别增加了66.60%和111.88%。作业高度影响了无人机喷施雾滴在采样点上的沉积量和沉积均匀性,当作业高度由1.5 m增加至2.5 m时,单旋翼机喷施的雾滴在采样点上的沉积量和沉积均匀性分别降低了19.3%和53.6%、多旋翼机分别降低了48.7%和22.9%。在4种喷施条件下,单旋翼机在采样点上的沉积量比多旋翼机同条件下分别高出85.8%、26.5%、59.4%和123.4%。单旋翼机在1.5 m和46.67 mL·hm~(–2)作业条件下,农药对稻飞虱Nilaparvata lugens、稻纵卷叶螟Cnaphalocrocis medinalis、稻秆潜蝇Chlorops oryzae、细菌性条纹病及稻瘟病5种水稻病虫害的防治效果最好,防效分别为87.63%、76.67%、84.08%、59.26%和82.33%;多旋翼机在1.5 m和66.67 mL·hm~(–2)作业条件下,农药对上述水稻病虫害的防治效果最好,防效分别为86.54%、78.62%、89.47%、66.67%和83.33%。【结论】2种植保无人机由于旋翼风场不同,导致雾滴沉积效果不同,单旋翼植保无人机喷施效果更好;2种无人机喷施的农药最终对水稻病虫害的防治效果无明显差异,且防治效果均达到国家防效标准。

Operational effects of unmanned helicopters for pesticide spraying in rice field

Objective To test and compare the operation effects of single-rotor unmanned aerial vehicle (UAV) type HY-B-15L and multi-rotor UAV type MG-1S on pest and disease control in rice field.Method The mixing solution of rhodamine-B and nano-pesticide was selected to spray in rice field, and field spraying experiments were carried out by changing the working altitude of helicopter and the amount of pesticide spraying. The polyester fiber cards and water-sensitive papers deposited by droplets were collected and analyzed by fluorescence spectrophotometer and image analysis software "DepositScan" to obtain deposition effects of the droplets.Result The deposition of droplets increased with the increase of pesticide application. Compared with 46.67 mL·hm^-2 pesticide, when pesticide application was 66.67 or 100.00 mL·hm^-2, the deposition of droplets sprayed by single-rotor UAV increased by 48.50% or 137.73% respectively, while the deposition of droplets sprayed by multi-rotor UAV increased by 66.60% or 111.88% respectively. The spraying height of UAV influenced the deposition and uniformity of droplets on the sampling point. When the spraying height ascended from 1.5 m to 2.5 m, the deposition and uniformity of droplets decreased by 19.3% and 53.6% respectively for single-rotor UAV, and decreased by 48.7% and 22.9% respectively for multi-rotor UAV. The spraying performances of single-rotor UAV were better than those of multi-rotor UAV under four spraying conditions. Compared with multi-rotor UAV, the deposition of single-rotor UAV increased by 85.8%, 26.5%, 59.4% and 123.4% from treatment 1 to treatment 4. When single-rotor UAV worked at the height of 1.5 m and a dosage of 46.67 mL·hm^-2, the preventive effect of pesticide was the best which were 87.63%, 76.67%, 84.08%, 59.26% and 82.33% respectively against Nilaparvata lugens, Cnaphalocrocis medinalis, Chlorops oryzae, bacterial leaf streak and rice blast. When multi-rotor UAV worked at 1.5 m and a dosage of 66.67 mL·hm^-2, the preventive effects against those rice pests and diseases were close to the former and were 86.54%, 78.62%, 89.47%, 66.67% and 83.33% respectively.Conclusion Because of different wind field below the UAV rotor, the droplet deposition of two UAVs are different. The spraying effect of single-rotor UAV is better than that of multi-rotor UAV, but there is no significant difference of control effect between two UAVs. The preventive effects of pesticides sprayed by both UAVs can reach the criterion of China.