福建安溪茶树种质资源遗传多样性与铁观音衍生品种遗传关系

The diversity of tea germplasm resources and genetic relationship of‘Tieguanyin’-derived varieties in Anxi,Fujian,China

为更好地保护、鉴定评价和利用安溪茶树种质资源,采用单核苷酸多态性(SNP)分子标记技术对安溪茶树种质资源的遗传多样性和铁观音衍生品种的遗传关系进行分析,并进行了主坐标分析、层次聚类树分析、种群结构分析和遗传距离分析,此外,还构建了铁观音及其衍生品种的DNA指纹图谱,并计算了其遗传相似系数。结果显示,共筛选出53个适用于鉴定安溪茶树种质资源基因分型的高多态性位点,观测杂合度平均值为0.322,期望杂合度平均值为0.281,说明安溪茶树种质具有较为丰富的遗传多样性;安溪4个乡镇产区茶树群体间的遗传距离在0.068~0.269。供试样品可分为2个组,组Ⅰ主要包括西坪、虎邱和湖上等产区的茶树种质,种质间交流频繁;组Ⅱ主要由福田乡产区的野生型地方茶树种质组成,福田乡茶树种质资源相对集中且独立。DNA指纹图谱可以精准鉴定铁观音及其衍生品种,铁观音衍生品种具有较为丰富的多样性,其中铁观音与金牡丹、紫玫瑰、新选211的遗传相似系数较大。综上,安溪县茶树种质资源多样性丰富,在铁观音衍生品种中,金牡丹、紫玫瑰和新选211与铁观音的遗传相似度更高。

In order to better protect,evaluate and utilize Anxi tea germplasm resources,the genetic diversity of Anxi tea germplasm resources and the genetic relationship of‘Tieguanyin’-derived varieties were analyzed by single nucleotide polymorphism(SNP)molecular marker technique.Principal coordinate analysis,hierarchical clustering tree analysis,population structure analysis and genetic distance analysis were carried out.The DNA fingerprinting of‘Tieguanyin’and its derived varieties were also constructed,and their genetic similarity coefficients were calculated.The results showed that a total of 53 high polymorphic loci suitable for genotyping of Anxi tea germplasm resources were screened out.The average observed heterozygosity was 0.322,and the average expected heterozygosity was 0.281,indicating that Anxi tea plant germplasm resources had rich genetic diversity.The genetic distance between tea populations in the four townships of Anxi was 0.068-0.269.The tested samples could be divided into two groups.Group I mainly included tea plant germplasm resources from Xiping,Huqiu and Hushang,with frequent exchanges among germplasm resources.GroupⅡwas mainly composed of wild-type landrace tea germplasm resources in Futian,and the tea plant germplasm resources in Futian were relatively concentrated and independent.DNA fingerprinting could accurately identify‘Tieguanyin’and its derived varieties.‘Tieguanyin’-derived varieties had rich diversity,among which‘Tieguanyin’had a large genetic similarity coefficient with‘Jinmudan’,‘Zimeigui’and‘Xinxuan 211’.In summary,the diversity of tea plant germplasm resources in Anxi County was rich,‘Jinmudan’,‘Zimeigui’and‘Xinxuan 211’had higher genetic similarity with‘Tieguanyin’.