Abstract:To reduce labor intensive, increase pesticides availability and decrease loss and other issues, the 3WPZ-4 type grape sprayer matching on model PT-115 multifunctional self-propelled chassis was developed, which contained the technology of ultrasonic target probe, flexibility discharge pipes air-assisted precision spray and integrated control. The 3WPZ-4 type air-assisted grape sprayer with 1600L tank can operate for four rows wine grape at the same time and the designed spray pressure was form 0.5MPa to 1.0MPa which adapted to 2.5~3.5m wine grape row spacing. Four years wine grape pesticides application test showed that the spray water volume of 3WPZ-4 type air-assisted grape sprayer was from 37.4L/min to 78.7L/min, droplet median volume diameter was form 132.1μm to 251.1μm. Without precision target system and no air-assisted, using 1.2mm nozzle at 1.0MPa spray pressure, the minimum pesticides deposition rate was 53.24%, the maximum loss rate was 15.53% and drift rate was 31.23% at spray water volume of 801.2L/hm2. With air-assisted, using 1.5mm nozzle at 1.0MPa spray pressure, the maximum deposition rate was 71.90%, and the minimum drift rate was 15.68% at spray water volume of 1005.4L/hm2. Using 1.2mm nozzle at 0.5MPa spray pressure with air-assisted, the minimum loss rate was 10.77% at spray water volume of 408.4L/hm2. Without air-assisted, average pesticides deposition rate was 58.83%, average loss rate was 14.48%, and the average drift rate was 26.69%. With air-assisted, average pesticides deposition rate was 68.94%, average loss rate was 12.08%, and average drift rate was 18.98%. With air-assisted, average pesticides deposition rate was increased by 17.2%, average loss rate was reduced by 16.56%, and average drift rate was lowered by 28.87%. When using precision target system, the average spray water volume error was 2.90%, average pesticides deposition rate was 65.76%, average loss rate was 13.40%, and average drift rate was 20.84%.