Abstract:Due to spray drift and less penetration into the crop canopy by conventional pesticide application methods, a wind-curtain air-assisted spraying system under a no-canopy condition was evaluated by using electronic scale to weigh deposition on the plane. Overall deposition and distribution of electrostatic spray and un-electrostatic spray on different heights with different wind velocities was investigated. Effects of the field of wind-curtain on deposition and distribution of spraying was analyzed. Results showed that the wind-curtain decreased transversal diffusion of spray drop which centralize spray deposition in narrow region near the centre and repress spray drift. The air flow enhance disturbance of spray field which enhanced uniformity of deposition of electrostatic spray and un-electrostatic spray along the axial direction of the boom. The air jet increased momentum of small droplets far away the nozzle and the greater air curtain velocity the greater impact on distribution of spraying.