Abstract: To develop a soluble concentrate (SL) of Matrine suitable for aerial spray and determine its wettability and spray performance, we employed a single factor test to screen the types and quantities of wetting dispersants of Matrine SL, to test the heat storage and low temperature stability of each formula, to determine the static surface tension (SST) and dynamic contact angle (DCA) of preparation using optical contact angle measuring instrument, and to measure the droplet density and coverage of Matrine SL in drone spray using water-sensitive paper. According to the results, when the dosage of BY-125, a wetting agent suitable for Matrine SL, was between 1%-5%, the preparation possessed a better stability. When the dosage of BY-125 increased, SST and DCA of Matrine SL gradually decreased. With 1.5% Betaton was added into the diluent, SST and DCA decreased by 48.78%-52.39% and 56.59%-62.81%, respectively. When the diluent was tank-mixed with 1.5% Betaton, the control of 1% Matrine SL on Schizaphis graminum (Rondani), droplet density and coverage increased significantly, compared with that without Betaton. The current results show that BY-125 can be used to make Matrine SL preparation, with the optimal dosage of 1%, and that the Matrine SL tank-mixed with 1.5% Betaton is of high wettability and deposition performance, which optimizes the spray performance and control efficiency of Matrine SL in drone spray.

Key words: matrine, soluble concentrate, UAV, wettability, spray performance