COMPARE EFFICACY BETWEEN KNAPSACK SPRAYER AND UAV SPRAYER APPLICATION IN CHEMICAL SPRAYING: A CASE STUDY OF GARLAND CHRYSANTHEMUM

Abstract

In the field of pesticide spraying for crop diseases and insect pests, the deposition structure of pesticide droplet includes coverage rate, droplet diameter, and droplet coverage density, which is one of the most important factors affecting the spraying effect. In this study, two spraying devices, knapsack sprayer and unmanned aerial vehicle (UAV), were used to spray twice on the leaf front and back of Garland Chrysanthemum, the relevant parameters were obtained, and the effects of spraying and pest control were evaluated by WaterSensitive Paper and Sticky Insect Paper. This study is expected to pave the way for the use of knapsack and UAV sprayers in Taiwan and other areas for accurate pesticide application on Chrysanthemum crops. At the result of spraying on leaf front, the droplets number of UAV was more than knapsack sprayer’s (1663 verse 1081), while the coverage rate of knapsack sprayer was higher than UAV’s (38.7% verse 25.8%). The droplet diameter of UAV was smaller than knapsack sprayer (58.5µm verse 241.1µm); and the droplet coverage density of UAV was larger than knapsack sprayer’s (49.3/cm2 verse 32/cm2).On the other hand, the droplet deposition sprayed by UAV on the leaf back was better than knapsack sprayer as well. The above results showed that the parameters of UAV's droplet deposition were better than those of knapsack sprayer's. The completed evaluation of droplet deposition parameters listed in (Table12-Leaf Front) and (Table13-Leaf Back). Besides, in terms of pest control effect, UAV performed slightly better than knapsack sprayer as well (83% verse 73%). The result of the study might provide a reference for future researchers and farmers who are growing Garland Chrysanthemum to choose the suitable equipment and improve the spraying effect.