Studies On Enzymes Related To Anthocyanin Biosynthesis And Degradation In The ’Hong Yang’ Kiwifruit

In order to explore the physiological mechanism of anthocyanin metabolism in’Hongyang’ kiwifruit,the 5-year-old ’Hongyang’ kiwifruit tree was used as the experimental material.The correlation between the dynamic changes of anthocyanin content during the fruit development and the activities of PAL,CHI,DFR,UFGT,β-galactosidase,P-xylosidase,PPO and POD in biosynthetic degradation pathway were studied.The effect of soluble sugar and starch on the accumulation of anthocyanins was also studied.The results showed that:(1)the fruit flesh colour of ’Hongyang’ kiwifruit was green at 41 days after blooming stage.With the development of the fruit,the inner pericarp appeared red and gradually deepened,while the outer pericarp appeared still no red.(2)Corresponding to the changes of red colour in fruit,the contents of anthocyanins in inner and outer pericarp were extremely low at 41 days after blooming.From 56 to 131 days after blooming,the contents of anthocyanins in inner pericarp increased significantly,while in outer pericarp remained at a very low level.(3)The content of soluble sugar and starch had positive correlation with the accumulation of anthocyanin in fruit flesh,which indicated that the concentration of soluble sugar could affect the synthesis degradation of anthocyanin,and the starch could indirectly regulate anthocyanin by the conversion into sugar.(4)During the growth and development of fruits,the dynamic changes of anthocyanin contents in the inner pericarp were significantly positively correlated with PAL,CHI,P-galactosidase activity,and negatively correlated with PPO activity;in the outer pericarp were significantly positively correlated with the activities of PAL,DFR,PPO and POD,but significantly negatively correlated with the P-xylosidase activity.Although UFGT showed no significant negative correlation with anthocyanin,but the activity of UFGT was higher.In conclusion,PAL,CHI,DFR,UFGT,P-galactosidase,PPO and POD may be important enzymes in the biosynthesis and degradation pathway of anthocyanins in’Hongyang’kiwifruit.