Leaf color transformation and related physiological changes for five Camellia cultivars

To study leaf color c hanges and their relationship to physiological indexes, five Camellia cultivars with 10-15 years of age were used to measure leaf color rate of change, the contents of photosynthetic pigments, anthocyanin, soluble sugar, and soluble protein. Leaves were measured every 30 d during the colorchanging period. Results showed that in winter for old leaves of ‘ Mei Yu', 70% changed to a bronze red color; whereas for ‘Xiao Fenyu' 60% changed to an ochre color, both of them have high ormental value in winter. New spring leaves of the five cultivars were bright red with the red period lasting up to 1 month. Anthocyanin content was the key factor in leaf color change. In winter, soluble protein had no direct relationship on the photosynthetic pigments and anthocyanin; whereas, a positive relationship between soluble sugar content and anthocyanidin content was found with ‘ Mei Yu' and ‘ Xiao Fenyu'. Soluble sugar content for new spring leaves was lower than old winter leaves, and soluble protein content in spring leaves was higher than old winter leaves.