26份云南大叶茶树品种资源生化成分多样性分析.

[Objective] Through conducting a in-depth study on the variety diversity of Yunnan big-leaf tea, analyzing the diversity of their biochemical components with corresponding varieties and screening the specific varieties, the purpose of this paper was to provide theoretical guidance for the exploration, utilization, reproduction of those specific varieties. [Method] The biochemical components of autumn tea of 26 Yunnan big-leaf tea varieties were determined, and based on the results, principal component analysis and cluster analysis were carried out. [Result] The biochemical components of 26 varieties had rich diversity and variation, with an average coefficient of variation of 25.53%. Among the four conventional biochemical components, the largest coefficient of variation was amino acid, up to 14.13%. Among the catechin components, catechin had the largest coefficient of variation, reaching 63.51%. Multivariate principal component analysis showed that the first three principal components accounted for 77.179% of the diversity of biochemical components of 26 varieties, the variance accounted for by the first principal component was 50.165%, the contribution of phenol ammonia ratio was the largest; the variance accounted for by the second principal component was 16.894%, the contribution of epicatechin (EC) was the largest; the variance accounted for by the third principal component was 10.120%, and the contribution of epigallocatechin gallate (EGCG) was the largest. Based on the clustering of 12 biochemical components of 26 variety resources, three groups were formed. The first group mainly was Yunkang series variety resources, which were mainly characterized by high contents of water extract, tea polyphenols, phenol ammonia ratio, total catechin, catechin DL-C and epigallocatechin gallate (ECG), and low contents of amino acids and epigallocatechin (EGC) . The second group was Yunnan large leaf population resources, which were characterized by high contents of amino acids, caffeine and EC, and low contents of total catechin, EGCG and ECG, The third group was mainly artificial hybrid variety resources, which were characterized by high contents of EGC and EGCG, and low contents of water extract, tea polyphenols, caffeine, phenol ammonia ratio, catechin DL-C and EC. The contents of four conventional components of the three groups were relatively consistent, and there were differences in phenol ammonia ratio and catechin content. [Conclusion] 26 Yunnan big-leaf tea variety resources have rich genetic diversity, with 26 high tea polyphenol resources, 1 high caffeine resources and 15 high catechin resources were preliminarily screened. [ABSTRACT FROM AUTHOR]