Determination of application parameters for cotton defoliants in the Yellow River Basin

Abstract

The differences in the growing conditions and the cotton varieties used in the cotton-growing areas in Xinjiang and theYellowRiver Basin result in different operating parameters required for unmanned aerial vehicle (UAV)-based plant spraying operations in the two regions. In this experiment, a multi-rotor plant protection drone was used for the application of cotton defoliant in theYellowRiver Basin to determine the optimum dosages of the defoliant ethepon. The experiment consisted of six treatments;40 g of thidiazuron, 1 mL of an additive, and different amounts of ethephon (50, 70, 90, 110, and 130 mL) were applied. The defoliation rate was measured on the 5, 10, 15, and 20 days after the chemical application and the correlation between the ethepon concentration and the defoliation rate as well as the cotton boll opening rate was determined. The results showed that the application of 90 mL ethephon resulted in the optimal defoliation effect and ripening of the cotton on 5 and 15 days respectively after the chemical application. It was found that the ethephon application had a larger effect on the cotton defoliation than the ripening rate. The results of this study provide reference data for the use of a plant protection drone for applying cotton defoliants in theYellowRiver Basin. Keywords: drone, UAV, cotton defoliant, ethephon, defoliation rate,Shandong DOI:  10.33440/j.ijpaa.20190201.0016  Citation: Han X, Yu J Y, Lan Y B, Kong F X, Yi L L.  Determination of application parameters for cotton defoliants in theYellowRiver Basin.  Int J Precis Agric Aviat, 2019; 2(1): 51–55.