Abstract:In order to reduce the comprehensive cost of orchard spray, it is necessary to evaluate the resource consumption level of application machinery. A typical airassisted sprayer, a singlerotor and a sixrotor plant protection unmanned aerial vehicle (UAV) were applied for spray test. The results showed that the droplet deposition density of three spraying machines in each layer were all more than 25 droplets/cm2. The droplet distribution uniformity decreased in vertical canopies seen from the direction of blowing. Observed from the horizontal direction, the droplet distribution uniformity was also decreased from outside to inside layers. The highest coefficient of variation (CV) values were separately 63.54% and 79.19%. In terms of the droplet penetration, the airassisted sprayer was superior with the low CV value nearby 5.35%. While the CV value of the singlerotor plant protection UAV was 35.20% in the horizontal direction and the CV value of sixrotor plant protection UAV was 40.77% in vertical direction with bad penetration. The droplet loss on the ground of the singlerotor and sixrotor plant protection UAV were 2.78% and 12.50% of that of the airassisted sprayer, respectively, which reduced the pesticide waste. Then, two resource consumption evaluation models of application machinery were constructed using two linear weighting methods (objective weighting method based on coefficient of variation and subjective weighting method) with the evaluation indexes of water, pesticide, labor, time, and energy consumption. The results showed the descending order with resource consumption of the singlerotor plant protection UAV, the sixrotor plant protection UAV and the airassisted sprayer. The CV values of comprehensive evaluation index in two evaluation methods were 110.2% and 74.2%, which indicated that the evaluation model based on the objective weighting method was better. The conclusions provided a reference for farmers to choose a suitable application machinery and reduce the comprehensive cost in orchard.
