Abstract:
The evaporation of droplet on crop leaf surface is a key progress in the pesticide spraying application when the droplet deposited on target crops. It also has an effect on the utilization rate of pesticide and the control efficiency. Studies demonstrated that there are many evaporation modes during the whole evaporation period such as CCR (Constant contact radius) mode, CCA (Constant contact angle) mode, Mixed mode and so on. Besides, the evaporation mode has an influence on both the profile of the droplet and the whole evaporation time. To understand the evaporation kinetics of pesticide droplets on the target crop, the evaporation dynamics of droplets on the smooth solid interface, artificial modified interface with different microstructure and on different plants surfaces was reviewed. Recent literature revealed that the evaporation rate of droplet on the smooth solid surface has a linear trend with the evaporation time. On the artificial modified interface, the evaporation rate and the evaporation mode are affected by the solid morphology. On different leaf surfaces, wettability is an important factor in the process of the droplet depositing, withholding, spreading and penetrating on leaf surfaces. In general, the droplet spreading area and the evaporation rate are proportion to the wettability of the leaf surfaces. With better understanding of the evaporation dynamics of the pesticide droplet on target crop leaves, the evaporation time on crop leaf surfaces can be regulated through the damage characteristics of pests and effective prevention of dosage. And this provides the theory basis for suitable use of surfactant and for improving the effective utilization of pesticide.