四川九龙古茶树种质资源农艺性状遗传多样性研究

The Phenotypic Diversity Analysis of Ancient Tea Germplasm Resources in Jiulong County,Sichuan Province,China

为探究甘孜九龙古茶树种质资源的分布区域、形态特征和农艺性状的遗传多样性,通过基本统计分析、变异系数、多样性指数、主成分分析和聚类分析,对67份九龙古茶树种质资源的21个质量性状和12个数量性状进行了遗传多样性分析和评价。结果表明:九龙古茶树资源农艺性状变异丰富,除树型和树姿外,质量性状的遗传多样性指数范围为0.17~1.27,平均为0.82,其中以花瓣颜色多样性指数最小,果实形状的多样性指数最大;数量性状变异系数范围为1.38%~29.94%,平均为15.27%,以叶面积的变异系数最高,萼片数的变异系数最低。主成分分析显示,前11个主成分累计贡献率在76.49%,其中叶宽、叶长、叶色和花瓣颜色等性状是九龙古茶树种质资源农艺性状表现出差异的主要因素。21个质量性状聚类分析结果显示,在欧式距离为16.9时,可将67份九龙古茶树种质资源划分为4个类群,聚类结果与海拔高度及地理位置无明显相关性。本次调查的古茶树种质资源中有13份种质位于海拔2400 m以上,长势良好,展现出良好的抗寒性和抗旱性。此外,还有2份种质花瓣颜色特异,1份种质籽粒较大且结果率高。研究结果为九龙古茶树种质资源收集、保护和利用奠定一定基础。

To explore the distribution area,morphological characteristics,and genetic diversity of agronomic traits of Jiulong ancient tea germplasm resources in Ganzi,Sichuan province,China.21 qualitative traits and 12 quantitative traits in 67 Jiulong ancient tea germplasm resources were evaluated,followed by the genetic diversity using basic statistical analysis,coefficient of variation,diversity index,principal component analysis and cluster analysis.The results showed that Jiulong ancient tea resources had rich variation at different agronomic traits.Except for tree type and growth habit,the genetic diversity index of qualitative traits ranges from 0.17 to 1.27,with an average of 0.82.Among them,the smallest of diversity index is petal color,and the largest is the fruit shape.The coefficient of variation of quantitative traits ranges from 1.38%to 29.94%,with an average of 15.27%.The highest coefficient of variation is leaf area,while the lowest is the number of sepal.Principal component analysis showed that the cumulative contribution rate of the first 11 principal components was 76.49%,among which leaf width,leaf length,leaf color,and petal color were the main factors that affected the differences at agronomic traits of Jiulong ancient tea germplasm resources.The cluster analysis showed that these ancient tea resources divided into four categories when the distance coefficient was 16.9,and the clustering results have no significant correlation with altitude and region.Among the germplasm resources investigated in this study,13 of them are located at an altitude of 2400 meters or above,showing good growth,satisfactory cold and drought resistance.In addition,there are two germplasms with unique petal color and one germplasm has larger grains and higher fruiting rate.The results laid a foundation for the collection,protection,and utilization of germplasm resources of Jiulong ancient tea germplasm resources.