Method of promoting sweet cherry defoliation in winter in southern China
The sweet cherry varieties Hongmi,Zaodaguo and Yanyang were used as experimental materials to investigate the SPAD value,nitrogen content and defoliation rate by spraying urea,ethephon,abscisic acid and their combined solutions,so as to explore the method for promoting the defoliation of southern sweet cherry leaves.The results showed that spraying 5%pure urea solution,800 times ethephon solution,400 mg/L abscisic acid solution,5%urea solution+800 times ethephon solution,5%urea solution+50-100 mg/L abscisic acid solution could effectively promote the leaf defoliation of sweet cherry,and would not cause tree damage due to rapid leaf defoliation.5%urea solution+40 mg/L abscisic acid solution+600-1,200 times ethephon solution was an excellent defoliant suitable for defoliation of sweet cherry leaf in winter in southern China.The defoliation rate could reach 90%within 15 days after spraying.Through experiments,a variety of suitable methods for defoliation of leaves of sweet cherry in winter in southern China were explored,and suitable defoliation methods were selected according to climatic conditions of different years to promote dormancy,reduce nutrient loss caused by difficult defoliation,and store the nutrients for the next year's flowering and fruiting.
sweet cherrydefoliationureaethephonabscisic acidsouthern region