SSR标记鉴定浙江省主要无性系茶树品种的研究

Application of SSR Markers in Cultivar Identification of Clonal Tea Plant in Zhejiang Province,China

为促进浙江省茶树育种的发展,利用SSR引物对浙江省茶树育成品种的遗传多样性进行了研究,筛选出可用于鉴别浙江省茶树品种的核心鉴定引物和标准品种,并进一步应用于未知茶苗身份鉴定。首先,利用35对SSR引物研究了36个茶树育成品种,并进行聚类分析;然后,根据电泳谱带和基因型筛选出核心鉴定引物和标准品种;最后,对4株未知茶苗进行了身份鉴定。结果表明：共有34对引物表现出多态性,各品种基本按遗传背景聚类,重复样本间遗传距离介于0-0.094;有10对引物确定为核心鉴定引物,8个品种为标准品种;4株未知身份茶苗中,NH-01属于乌牛早品种,另外3株并非浙江现有品种。本研究认为,核心鉴定引物在两个浙江育成品种间差异引物对≥2时,应判定为不同品种;差异引物对≤1时,应判定为相同品种或极相似品种,必要时应引入其余24对引物计算遗传距离进一步验证,遗传距离〉0.140判定为不同品种,遗传距离≤0.140判定为同一品种。

Thirty six tea cultivars origined from Zhejiang province were analyzed using SSR markers. The genetic diversity and cluster analysis shown that： totally 121 alleles and 187 genotypes were amplified by 34 polymorphism markers,with an average of 3. 6 and 5. 5,respectively; the polymorphism information content（ PIC） were ranged from 0. 02 to 0. 74,with an average of 0. 45; most similar cultivars were classified according to their genomic background. Ten core SSR markers fitting for cultivar identification were confirmed,and were used to evaluate 4 unknown varieties. It wan believed that if more than 2 core primer pairs were different between 2 tea plants,they should be defined as different varieties,otherwise they wete same variety or highly similarity varieties. If necessary,the value of genetic distance should be used to distinguish highly similarity varieties,if the value 0. 140 they should be defined as different varieties,otherwise they were same variety. We believed that this study would promote the breeding research of tea plant in Zhejiang province.