ISSR在茶树品种分子鉴别和亲缘关系研究中的适用性分析

ISSR是最近发展的一种基于PCR技术的分子标记,已在植物种质鉴别和遗传多样性分析等方面得到广泛应用。本文对其在茶树品种分子鉴别和亲缘关系的适用性进行分析,利用筛选出的8个ISSR引物对六个茶树品种的基因组DNA进行扩增,共扩增出99条带,多态性平均为79.6%。由两个ISSR引物TRI22和TRI30扩增的指纹图谱可清楚区分六个不同品种,利用特殊ISSR标记的存在或缺失以及不同标记组合也可以鉴别不同品种。根据Nei-Li系数将六个品种聚为两类,茂绿、翠峰、青峰、迎霜和劲峰五个品种聚为一类,龙井43单独聚成一类,聚类分析证实了它们的亲缘关系。结果显示,ISSR作为一种信息量高、重演性好的分子标记,应用于茶树品种鉴别和亲缘关系分析是非常有效的。

Analysis on Applicability of ISSR in Molecular Identification and Relationship Investigation of Tea Cultivars

Inter-simple sequence repeat (ISSR) is a recently developed PCR-based molecular technology. It has been widely used in genetic diversity, phylogenetic studies, gene tagging, genome mapping and evolutionary biology in a wide range of crop species due to its simple, quick, efficient, high reproducibility and low expense. In this study, the applicability of ISSR on molecular identification and relationship analysis of tea cultivars were investigated. A total of 99 bands were amplified by eight ISSR primers in six tea cultivars and the average polymorphism was 79.6%. The six tea cultivars could be clearly distinguished by ISSR fingerprinting amplified with primers TRI22 and TRI30, and also by the presence or absence of specific ISSR markers and their combination. Six cultivars were divided into two groups by cluster analysis. Maolu, Cuifeng, Qingfeng, Yingshuang and Jinfeng were in one group and Longjing 43 in the other. The relationship of six tea cultivars were validated by cluster analysis based on ISSR. The results indicate that ISSR is a useful tool for molecular identification and relationship analysis of tea cultivars.