云南茶树种质资源的表型遗传多样性

Genetic Diversity of Tea Germplasm Resources in Yunnan Province Based on Phenotypic Characteristics

对云南10个地区的830份茶树种质资源主要表型性状的遗传多样性分析和比较表明，云南茶树种质资源具有丰富的表型遗传多样性，13个描述型性状的遗传多样性指数在0．64～1．40之间，平均为1．04，以芽叶色泽较高，叶基较低；不同地区的茶树资源遗传多样性指数在0．76～0．99之间，以红河地区较高，其次是临沧和文山地区，以昭通地区较低。14个数值型性状的变异系数在10．27％～48．14％之间，平均为26．43％，以酚氨比较大，水浸出物含量较小：不同地区的茶树资源变异系数在16．09％～25．75％之间，以文山、红河地区较大，昭通、大理地区较小。茶树资源表型性状的遗传多样性和变异水平显示东南部〉西部〉东北部的趋势。通过聚类分析，10个地区的茶树资源划分为3个地理组，东北部的昭通和东南部的红河各单独聚为一组，其他8个地区聚为第3组，显示云南茶树资源存在东南部、西部、东北部生态地理的分化，初步推断东南部为云南茶树资源表型遗传多样性分布中心。

Yunnan province of China is regarded as the origin center of tea plant, where maintains rich genetic resources of tea plant and its relative species. This study was to understand the phenotypic diversity of these germplasm resources. A total of 830 accessions of Thea section were collected from 10 regions of the province and 27 traits including 13 descriptive and 14 numerical characteristics were tested. In the descriptive characteristics, the genetic diversity index （DI） ranged from 0.64 to 1.40 with an average of 1.04. The largest and the smallest DI values were observed in young shoot color and leaf base shape, respectively. The regional DI was the largest in Honghe （0.99）, followed by Lincang （0.93） and Wenshan （0.91）, and the smallest in Zhaotong （0.76）. In the numerical characteristics, average coefficient of variation （CV） was 26.43%, ranging from 10.27% of water extract to 48.14% of the ratio of polyphenol to amino acid. The regional CV was 16.09%-25.75%, of which Wenshan and Honghe had the highest value and Zhaotong and Dali had the lowest one. The genetic diversity and CV ofphenotypic traits showed a tendency of Southeast 〉 West 〉 Northeast. The clustering analysis showed that these germplasm resources were geographically clustered into three groups, i.e., Zhaotong, Honghe, and other-region group, respectively. These results demonstrate an obvious differentia- tion of tea germplasm resources among Southeast, West, and Northeast of Yunnan, and Southeast is primarily deduced as the distribution cemer of genetic diversity.