Influence factors of evaporation time of pesticide droplets on different tobacco leaves

One of the ways to obtain the high efficiency of pesticide spray applications is to study the evaporation time on different crop leaves. Three tobacco varieties (NC471、Yun110, and T66) were taken as experiment subjects. surfactants (Nongru 500#, Fairland2408, and Tech-408) were added into pesticide which were 10% Imidacloprid，70% Mancozeb and 40% Dimetachlone water separately. Droplet evaporation whole process and the data of evaporation time were measured by sequential images after the droplet was deposited. The results showed that there was no significant connection between the pesticide types and the droplet evaporation time on tobacco leaves. No matter surfactants were added or not, evaporation time on T66 tobacco leaves was significantly shorter than that on NC471 and Yun 110. The surface characteristics of the 3 tobacco leaves were investigated and the results showed that T66 leaves had less stomata and more fine fur obvious difference with other two tobacco leaves. Therefore, the tobacco leaves with less stomata and more fine fur could shorten the droplet evaporation time. The tobacco variety and the surface fine structure acted as critical factors that influenced the droplet evaporation time. The experiment also showed that evaporation time of pesticide droplets would be shortened after the surfactants were added. The droplet evaporation time was shortened 64-78 s when Fairland2408 was added. The droplet evaporation time was shortened 61-74 s and 12-26 s when Tech-408 and Nongru 500# was added, respectively. The higher the surfactant concentration went, the shorter evaporation time of insecticide droplets would be. The results above-mentioned will provide scientific basis for how to control the absorbing speeds of leaves and obtain the high efficiency of pesticide spray applications on different tobacco leaves.