Effect of natural brassinolide on physiological,biochemical characteristics and fruit quality of‘Red Globe'grape

In this study,the different concentrations of brassinolide(0.2,0.4,0.6,0.8 mg/L)were sprayed on the 6years old ‘Red Globe'grape during the young fruit,berry expansion and color-changing period to investigate the effects of brassinolide(BR)on physiological characteristics and quality of grape.The results showed that the activities of SOD,POD and CAT were significantly higher while membrane permeability and MDA were lower under the treatments of 0.2mg/L and 0.4mg/L BR than that of control(spraying water).Free proline were significantly promoted with the spraying of 0.4 mg/L BR.The chlorophyll contents were significantly increased under all treatments compared with control,except the treatment of 0.8mg/L BR.The fruit cluster weight,single fruit weight,soluble solid and total phenol content were promoted with the spraying of 0.2mg/L and 0.4mg/L BR,while the titratable acidity were declined accordingly under these treatments.Fruit shape index of grape were largest with the spraying of 0.8mg/L.Different concentrations of BR had no significant effects on anthocyanin and flavonoids of grape.In conclusion,the spraying of 0.4mg/L BR was the best concentration for the‘Red Globe'grape.