基于SSR标记的小豆品种鉴定体系建立及应用

Establishment and Application of Variety Identification System Based on SSR Markers for Adzuki Bean(Vigna angularis)

小豆是中国重要的食用豆类作物,建立小豆品种鉴定体系有助于品种测试、种子市场监管等工作。本研究选择不同地理来源、表型性状差异较大的12个小豆品种为实验材料,筛选出59对扩增稳定、多态性较高的初选核心引物,在5’端进行荧光标记后,另选择96份小豆品种进行复筛,进一步决选出28对核心引物,构建了182个小豆品种的DNA指纹库。这些引物共检测到245个等位变异,等位变异数范围为2~20个,平均每对引物检测到8.75个等位变异;Nei’s基因多样性指数变化范围为0.27~0.89,平均为0.62;PIC值在0.246~0.877之间,平均为0.583。对核心引物未能区分开的品种进行1个生长周期田间种植对比鉴定,表明分子指纹聚类结果与基于表型的分类结果相同。本研究建立的基于毛细管电泳平台的小豆SSR分子标记品种鉴定体系,可用于小豆种质资源鉴定和遗传多样性分析、DUS测试辅助筛选近似品种、品种真实性鉴定等工作。

Adzuki bean is an important edible legume crop in China.The establishment of a variety identification system will help the variety testing and seed market supervision of adzuki bean.In this study,12 adzuki bean varieties of different origins with significant morphological differences were chosen as preliminary primer-screeners and 59 pairs of primary core primers with stable amplification,clear bands and high polymorphism were selected.These 59 pairs of primers were then labeled with fluorescence at 5’end,and re-screened with 96 adzuki bean varieties by capillary electrophoresis.28 pairs of core primers were finally selected and used to establish a SSR fingerprint database of 182 varieties.A total of 245 alleles were detected.For each pair of primers,the alleles detected ranged from 2 to 20,with an average of 8.75,the Nei’s gene diversity index ranged from 0.27 to 0.89,with an average of 0.62,the PIC value ranged from 0.246 to 0.877,with an average of 0.583.The varieties which could not be distinguished by core primers were compared in field for one growth cycle.The result of DNA clustering was the same as that of in-field morphological classification.In conclusion,the identification system of adzuki bean varieties can be used for germplasm resources identification and genetic diversity analysis,management of variety collections in DUS tests,and variety authenticity identification.