A Preliminary Study On Screening Special Tea Plant Germplasm Resources With High Caffeine And SSR Markers Related To High Caffeine

Caffeine is one of the crucial important factors in tea quality. It is also one of the component of tea that has physiological activity and wide uses. High caffeine content (>5%) resources, one hand, may be used as the improvement the capital stock of tea tree heredity. On the other hand, it may apply in the production, the direct massive extraction caffeine from the tea tree fresh leaf or takes the high caffeine tea processing raw material. In order to screen special germplasm resources of tea plant [Camellia sinensis (L. ) O.Kuntze] with high caffeine, 425 tea plant resources were utilized as material. According to the papers, 45 tea plant resources were screened as candidate. The biochemical contents of 45 tea plant resources were analyzed. At the same time, SSR Markers Related to High Caffeine were studied. The main content and results of this research were as follows:1. The biochemical content of 45 resources was analyzed. The result was as follow: there were non-linear between the content caffeine and amino acids or tea polyphenols. There were 3 resources in which the caffeine content exceeded 5%.The content caffeine of Q20, Q41 and Q45 was 5.10%, 5.19%, 5.46%, respective. And their tea polyphenols were 3.60%, 3.40%, 2.53%, their amino acids were 3.60%, 3.40%, 2.53%. These could be considered as special tea plant germplasm resources with high caffeine content and be used as important materials of both quality genetic improvement and the extraction of caffeine from tea plant. In addition, this study revealed findings: the caffeine content of Q33 and Q38 resources were below 2%. The content caffeine of them was 0.21% and 1.12%, and their tea polyphenols were 35.16% and 30.23%, their amino acids were was 0.72% and 0.46%.2. The caffeine content of spring tea shoots, summer tea shoots, autumn tea shoots in 45 resources were analyzed. The result was as follow: caffeine content of tea plant shoots varied greatly with resources. In spring tea shoots, summer tea shoots, autumn tea shoots, the caffeine contents in 45 resources were in the range of 0.21%-5.46%, 0.84%-6.41%, 1.16%-5.70%, the average were 3.99%, 4.33%, 4.19%, respectively. The variation coefficients were 3.99%, 13.79%, 10.90%, respectively. The caffeine contents in the shoot of the same resource different season, mostly: summer tea shoots > autumn tea shoots > spring tea shoots. In particular, there were Q20 and Q45 resources in which the annual average caffeine content exceeded 5%. In addition, this study revealed findings: the annual average caffeine content of Q33 and Q38 resources were below 2%.3. 10 resources were screening from 45 resources. 3 high caffeine(>5%), 2 lower caffeine(<2%) and 5 normal resources(2%-5%) were supplied for SSR-PCR. And then DNA of 10 resources were isolated by Reagent box, 29 pairs of SSR primers were used in SSR-PCR, among them ccmp3-1, ccmp3-2 related to high content caffeine were discovered during manytimes.