Comparison of Spray Deposition, Control Efficacy on Wheat Aphids and Working Efficiency in the Wheat Field of the Unmanned Aerial Vehicle with Boom Sprayer and Two Conventional Knapsack Sprayers

Abstract

As a new low volume application technology, unmanned aerial vehicle (UAV) application is developing quickly in China. The aim of this study was to compare the droplet deposition, control efficacy and working efficiency of a six-rotor UAV with a self-propelled boom sprayer and two conventional knapsack sprayers on the wheat crop. The total deposition of UAV and other sprayers were not statistically significant, but significantly lower for run-off. The deposition uniformity and droplets penetrability of the UAV were poor. The deposition variation coefficient of the UAV was 87.2%, which was higher than the boom sprayer of 31.2%. The deposition on the third top leaf was only 50.0% compared to the boom sprayer. The area of coverage of the UAV was 2.2% under the spray volume of 10 L/ha. The control efficacy on wheat aphids of UAV was 70.9%, which was comparable to other sprayers. The working efficiency of UAV was 4.11 ha/h, which was roughly 1.7–20.0 times higher than the three other sprayers. Comparable control efficacy results suggest that UAV application could be a viable strategy to control pests with higher efficiency. Further improvement on deposition uniformity and penetrability are needed.

Application method affects pesticide efficiency and effectiveness in wheat fields

“…showed that the spray method has a significantly effect on pesticide depositions and losses . Sprayer nozzles are also regarded as the key factor affecting droplet deposition and the biological efficacy of pesticide application . For this reason, we also investigated the effect of three different nozzle sizes under differing spray pressures on the droplet distribution of each pesticide.…”

“…37 Sprayer nozzles are also regarded as the key factor affecting droplet deposition and the biological efficacy of pesticide application. 17 For this reason, we also investigated the effect of three different nozzle sizes under differing spray pressures on the droplet distribution of each pesticide. The findings revealed that the volume average diameter (VAD) of droplets was proportional to the quantity of the nozzle sizes, with a negative relationship between spray pressure and VAD (Fig.…”

“…In the past 10 years, a number of spraying techniques have therefore been developed or modified with the aim of increasing deposition effectiveness, while reducing pesticide residues and operator exposure . For example, popularization of the boom sprayer has greatly reduced the labour intensity of spraying as well as dramatically improving the overall operating efficiency . Compared to common sprayers, unmanned aerial vehicles (UAVs) have numerous advantages, such as high efficiency, high pesticide utilization, reduced crop damage, and a low risk of pesticide poisoning, and have thus undergone rapid development in China .…”

“…16 For example, popularization of the boom sprayer has greatly reduced the labour intensity of spraying as well as dramatically improving the overall operating efficiency. 17 Compared to common sprayers, unmanned aerial vehicles (UAVs) have numerous advantages, such as high efficiency, high pesticide utilization, reduced crop damage, and a low risk of pesticide poisoning, and have thus undergone rapid development in China. 18 According to the statistics of the Chinese Ministry of Agriculture, more than 178 types of agricultural UAVs were in use in 2017.…”

Harvest-aid application strategy in different cotton planting densities by unmanned aerial vehicle

“…In recent years, UAVs have been widely used for spraying pesticides to control pests and diseases. The advantages of aerial application of pesticides by UAVs is substantial, such as high working efficiency, no harmful mechanical damage to crops and soil, low water consumption, reduced pesticide poisoning, high pesticide utilization and high flexibility [8][9][10][11][12][13][14][15][16][17] . Global positioning system (GPS), geographic information system (GIS), BeiDou navigation satellite system (BDS) and real-time kinematic (RTK) automatic navigation technology have been used in the flight control system for precision spraying by UAVs.…”