甜菜品种SSR指纹图谱的构建及遗传多样性分析

筛选出20对多态性高、带型清晰、重复性好的SSR标记引物对供试甜菜品种进行PCR扩增,根据扩增产物构建SSR指纹图谱,并分析其遗传多样性。结果显示,共检测出112个等位基因,平均每对引物5.6个,利用获得的等位基因计算遗传距离,107个品种的遗传距离变化范围在0.065~0.467之间,平均遗传距离0.298。Shannon’s多样性指数变异范围0.78~2.90;PIC值介于0.08~0.83;Nei’s指数介于0.39~1.87。利用类平均法（UPGMA）进行聚类分析,可将107个甜菜品种分为2个类群。类群Ⅰ29个品种,类群Ⅱ78个品种。类群Ⅰ和Ⅱ又可分为多个亚群。结果表明,每个甜菜品种有区别于其他品种唯一的数字指纹,说明用于试验的20对SSR标记适用于甜菜品种真实性的鉴定,同时甜菜品种指纹图谱库的构建也为甜菜品种鉴定提供技术基础。

Construction of SSR Fingerprint and Analysis of Genetic Diversity of Sugar Beet Varieties

The 20 pairs of SSR primers with high polymorphism, clear bands, and good repeatability were screened for PCR amplification of the tested varieties and the SSR fingerprint database was constructed according to the amplified products, and their genetic diversity was analyzed. The results showed that 112 alleles were detected with an average of 5.6 for each pair of primers. The obtained alleles were used to calculate the genetic distance and the variation range of the genetic distance among 107 varieties was 0.065-0.467 with an average genetic distance of 0.298. Shannon's diversity index variation ranged from 0.78 to 2.90. PIC values were between 0.08 and 0.83. The Nei's indexes were between 0.39 and 1.87. Cluster analysis by UPGMA could divide 107 sugar beet varieties into two groups. Group I included 29 varieties and group II included 78 varieties. Group I and II could be divided into several subgroups. The results indicated that each sugar beet variety had a unique digital fingerprint that was different from other varieties indicating that the 20 pairs of SSR markers used in the experiment were suitable for the identification of the authenticity of sugar beet varieties. Meanwhile, the establishment of the beet variety fingerprint database also laid a solid technical foundation for the identification of sugar beet variety.