Wetting and deposition characteristics of air-assisted spray droplet on large broad-leaved crop canopy

Yinlong Jiang; Zhou Yang; Xing Xu; Dongying Shen; Tingting Jiang; Bowei Xie; Jieli Duan

doi:10.3389/fpls.2023.1079703

Wetting and deposition characteristics of air-assisted spray droplet on large broad-leaved crop canopy

Front Plant Sci. 2023 Jan 20:14:1079703. doi: 10.3389/fpls.2023.1079703. eCollection 2023.

Authors

Yinlong Jiang^{1

2}, Zhou Yang^{1

2

3}, Xing Xu^{2

4}, Dongying Shen¹, Tingting Jiang¹, Bowei Xie¹, Jieli Duan^{1

2}

Affiliations

¹ College of Engineering, South China Agricultural University, Guangzhou, China.
² Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.
³ School of Mechanical Engineering, Guangdong Ocean University, Zhanjiang, China.
⁴ College of Electronic Engineering (College of Artificial Intelligence), South China Agricultural University, Guangzhou, China.

Abstract

Precision and efficient pesticide spraying is an important part of precision agriculture, banana is a large broad-leaved plant, with pests and diseases, has a high demand for spraying and pest control. The purpose of this study was to clarify the wettability of different pesticides on the banana leaf surface, and the effects of nozzle type and working parameters on the deposition distribution performance under air-assisted spray conditions. The wettability test results of different pesticides on banana leaf surfaces showed that the wettability of the adaxial side was always stronger than that of the abaxial side, the smaller the surface tension of the droplets, the better the wettability on the surface. The spray experiment was carried out on the previously developed air-assisted sprayer with the latest developed intelligent variable spray control system. Three types of nozzles were used to spray with different combinations of working parameters. The deposition distribution performance on the banana leaf surface was obtained by image processing using a self-compiled program. The experimental results show that the nozzle type, wind speed, and spray pressure have significant effects on the deposition distribution performance. Through the study of the interaction and coupling effect of nozzle type and working parameters on the spray droplet deposition distribution on both sides of banana leaves, the results show that under the conditions of hollow cone nozzle, 0.5Mpa spray pressure and 3-5 m/s wind speed, the spray coverage and droplet density are in the optimal state. This is mainly due to the low spray pressure and/or wind speed is not enough to make the banana leaves vibrate and improve the performance of pesticide deposition. excessive spray pressure and/or wind speed will cause large deformation of banana leaves and make them airfoil stable, which reduces the surface deposition performance. It is of great significance for promoting sustainable and intelligent phytoprotection.

Keywords: air-assisted spray; droplet density; large broad-leaved canopy; spray coverage; surface wettability.

Grants and funding

This study was supported by Guangdong Laboratory for Lingnan Modern Agriculture Project (Grant No. NT2021009), National Key Research and Development Program of China (Grant No. 2020YFD1000104), China Agriculture Research System of MOF and MARA (Grant No. CARS-31-10), and Guangdong Provincial Special Fund for Modern Agriculture Industry Technology Innovation Teams (Grant No. 2022KJ109).