Testing method and distribution characteristics of spatial pesticide spraying deposition quality balance for unmanned aerial vehicle

Pest Management Science

Lan

Huang

et al. 2019

128

BACKGROUND Unmanned aerial vehicles (UAVs) are a recently developed aerial spraying technology. However, the effect of spray volume variation on deposition and pesticide control efficacy is unknown. The effect of three UAV spray volumes (9.0, 16.8 and 28.1 L ha−1) using three different nozzle sizes on droplet deposition and wheat aphid and powdery mildew control efficacy was assessed. An electric air‐pressure knapsack (EAP) sprayer was used as a comparison. RESULTS Different spray volumes significantly influenced the deposition and control efficacy of the UAV and EAP. For the UAV, a low spray volume of 9.0 L ha−1 with a fine nozzle (nozzle LU120‐01) resulted in lower deposition and control efficacy. Optimal control efficacy was achieved with coarser nozzles (nozzles LU120‐02, ‐03) at > 16.8 L ha−1 volume with systemic insecticide, and at 28.1 L ha−1 with contact insecticide and fungicide. For EAP, a high spray volume led to run‐off, and a spray volume of 225 L ha−1 achieved better deposition and control efficacy. CONCLUSION The UAV had comparable deposition and efficacy control to the EAP at a higher spray volume (> 16.8 L ha−1) with coarse nozzles, but exhibited inferior deposition and efficacy control at a lower spray volume (<9.0 L ha−1) with fine nozzles. © 2019 Society of Chemical Industry

Section: Introductionmentioning

confidence: 99%

Field evaluation of an unmanned aerial vehicle (UAV) sprayer: effect of spray volume on deposition and the control of pests and disease in wheat

Pest Management Science

Lan

Huang

et al. 2019

128

“…29 With this test, it is found that when both operating height and wind speed change, the amount of droplet deposition could also be maintained in an ideal range. Wang et al found that increasing the operating height of a single-rotor UAV in a specific range could make the deposition of droplet deposition more uniform.…”

Section: Discussionmentioning

confidence: 92%

Meteorological and flight altitude effects on deposition, penetration, and drift in pineapple aerial spraying

Asia-Pacific J Chem Eng

Lan

Wen

et al. 2020

It is difficult for the handheld/backpack or ground machinery to spray pineapple plant fields because the plant profile is relatively inaccessible. In this situation, unmanned aerial vehicles (UAVs) are a good choice for easy access and no physical damage to the crops. Aerial spray quality and optimum application parameter settings can be influenced by many factors such as UAV type, UAV operating parameters, meteorological conditions, crop growth period, and pest species. The objective of this study was to investigate the effects of different meteorological conditions and UAV operating height on the spray application in pineapple fields. There were five treatments involving three UAV operating heights. Mylar cards, water-sensitive papers, and airborne concentrations of spray were sampled at various locations from −10 to 50 m downwind of the edge of the sprayed blocks. The results indicated that as the wind speed increased, the swath location was displaced 2 to 4 m, the percent area coverage uniformity changed along with the spray penetration capacity, and the 90% of total measured drift distance varied from 3.7 to 46.5 m. The test results again proved that droplet size and wind speed were significant factors in spray transport and impacted the UAV spray quality.

“…Formulation properties and droplet spectra are important for quantifying pesticide deposition . It is important to know whether the addition of Allura Red can influence the properties of pesticide formulations (viscosity, density and surface tension) or droplet spectra.…”

Section: Resultsmentioning

confidence: 99%

Water‐soluble food dye of Allura Red as a tracer to determine the spray deposition of pesticide on target crops

Gao

Pest Management Science

Zhou

et al. 2019

BACKGROUND Quantification of spray deposition on a target crop is of vital importance to optimize pesticide application. In traditional determinations of spray deposition, a large amount of organic solvent is used to extract pesticides from the target crops. In this study, a water‐soluble food dye of Allura Red was developed as a tracer to determine pesticide spray deposition on a rice target crop. RESULTS The addition of Allura Red does not obviously alter the physicochemical properties of pesticides (viscosity, density and surface tension) and droplet spectra. An ultra‐performance liquid chromatography (UPLC) analytical method was developed and validated to determine the deposition amount of Allura Red on rice plants. Method accuracy and precision for Allura Red were found to be satisfactory with recoveries of 96.07% to 107.48%. To validate the method, comparative deposition analyses were carried out using representative systematic and non‐systematic pesticides (nitenpyram and chlorothalonil) under the same spraying scenarios using a Potter spray tower. Allura Red and pesticides showed comparable deposition under the same application conditions with ratios from 0.98 to 1.21. A field trial using an unmanned aerial vehicle sprayer further indicated that the deposition rates for Allura Red and nitenpyram on rice seedling were 13.04% and 11.07%, with corresponding relative standard deviation values (n = 5) of 16.39% and 18.79%. CONCLUSION A laboratory test and field trial confirmed that the developed method of using Allura Red as a tracer for spray deposition assessment is feasible and practicable. © 2019 Society of Chemical Industry