Effects of Shading Treatments on Leaf Color Phenotype and Biochemical Composition of Tea Leaves

The "Wuyi special species C18" leaf was used as the raw material,and shading was carried out with 75% and 60% of black sun-shading net respectively,and the treatment with full light was used as a control. The effects of different shading treatments on the color phenotype and biochemical composition of purple shoots of tea plant were studied. After 15 days of shading treatment,the first leaves of Wuyi special species C18,which was treated with shading and full light treatment(CK),were used to determine the relative amount of chlorophyll,the total amount of anthocyanins,the total amount of tea polyphenols,and the catechin group fractions,total flavonoids and flavonoid aglycone content. The results showed that the weaker the shadeing degree was,the purpler the leaves were,the higher the anthocyanin content was;the relative content of chlorophyll was relatively low while the anthocyanin content was the highest under normal illumination;the relative content of chlorophyll was high while the anthocyacin content was low at 75% shading. The contents of anthocyanin and tea polyphenols,catechins,flavonoids and flavonoid aglycones decreased in different degrees with the increase of shading degree. The results indicated that the contents of tea buds,such as leaf color and anthocyanin,were affected by environmental light factors. This research laid a foundation for the further development and utilization of local bud specific tea tree resources and purple bud tea products.