不同来源地茶树种质资源表型性状遗传多样性分析

为了对不同来源地茶树种质资源进行鉴定评价和遗传多样性分析,以来自福建、广东、台湾的72份茶树种质作为研究对象,对其27项表型性状进行观测与分析。结果表明：72份茶树种质资源遗传变异性丰富,平均遗传多样性指数（H′）为1.30,其中数量性状（1.82）大于质量性状（0.94）,以梗粗的最大（2.15）;数量性状的平均变异系数（CV）为17.86%,以百芽重的最大（29.21%）,其次是发芽密度（23.46%）。相关性分析发现多个数量性状间的关系复杂,有22对性状的相关性达极显著水平（P˂0.01）,8对达显著水平（P˂0.05）;聚类分析结果显示,72份茶树种质在遗传距离为16时被划分为4个类群,各类群间的主要性状差异显著或极显著,且形态特征和进化类型各异;主成分分析表明,前10个主成分的特征值大于1,代表了27项表型性状76.04%的信息;根据主成分综合得分大小,筛选出综合得分前5的茶树种质可在茶叶新产品开发、茶树育种等方面加以利用。

Genetic Diversity Analysis of Phenotypic Characters of Tea Germplasm Resources from Different Origins

In order to evaluate and analyze the genetic diversity of the tea germplasm resources from different regions, 72 kinds of germplasm resources from Fujian, Guangdong and Taiwan were selected as the research objects, and 27 phenotypic characters were observed and analysed. The 72 tea germplasms were rich in hereditary variability. The average genetic diversity index (H′) was 1.30 while the index of stem thick of tea was the biggest (2.15), and among them the quantitative character (1.82) was higher than that of the qualitative character (0.94). The average coefficient of variation (CV) of quantitative character was 17.86% while the biggest was the hundred-bud weight (29.21%), followed by the index of germination density (23.46%). Besides, the correlation analysis found that the relationship between multiple quantitative traits was complex. The correlation of 22 pairs of characters reached extremely significant level (P˂0.01), and that for 8 pairs of characters reached significant level (P˂0.05). Cluster analysis showed that the 72 germplasm were divided into four groups when the genetic distance was 16, the main characters of each group were significantly different, and the various morphological characters and evolutionary types were different. Principal component analysis showed that the characteristic number of the first 10 principal components were greater than 1, which representing 76.04% information of 27 phenotypic characters. The top five germplasm were selected, which could be used in the new products development, tea breeding based on the comprehensive score of the principal components. This study would provide some references for the development and utilization of the germplasm resources of tea and the breeding of new cultivars.