Deposition and biological efficacy of UAV-based low-volume application in rice fields

Efficient and accurate application of pesticides can improve biological efficacy, reduce insecticide resistance, and protect the environment. The rapid development of unmanned aerial vehicle s (UAV) technology as a new method of pesticide application using low spray volumes demands scientific evaluation compared to conventional practices. The objective of this research was to analyze the effects of spray volume and tank-mix adjuvants on droplet deposition, canopy penetration, and control of rice blast disease and rice leaf roller when applied by UAV technology on rice. An electric backpack sprayer was used as the standard method of application for comparison. Increasing the spray volume and adding an adjuvant significantly increased droplet density, percentage of spray coverage, and control of rice blast and rice leaf roller for the UAV application. The control efficacy of the UAV sprayer was basically equal to or slightly worse than the backpack sprayer. These data indicate that a UAV application made at a spray volume of 18 L/hm 2 with the addition of a methylated crop oil adjuvant at panicle initiation provided excellent blast and leaf roller control. Keywords: UAV, adjuvant, biological efficacy, deposition, low-volume spray, rice DOI: 10.33440/j.ijpaa.20200302.86 Citation: Wang G B, Li X, Andaloro J, Chen P C, Song C C, Shan C F, et al. Deposition and biological efficacy of UAV-based low-volume application in rice fields. Int J Precis Agric Aviat, 2020; 3(2): 65–72.