利用SSR快速鉴定棉花品种真实性和纯度

利用SSR分子标记技术对棉花品种真实性和纯度进行分析研究,旨在为棉花品种提供分子鉴定依据。以具有代表性的棉花品种为材料,经过引物初筛和复筛,确定26对均匀分布于棉花染色体上的SSR核心标记。结果表明,26对核心标记在120份材料中筛选得到138个等位位点,其中129个为多态性位点,多态性比率达93.48%。以标准样品为对照,利用26对核心标记对10份棉花常规种进行真实性鉴定,发现仅有源棉6号与标准品种的DNA图谱高度一致,其他9份常规种与标准品种均存在8~18个差异位点,分子鉴定结果与田间鉴定相符。另外分别筛选5对特征引物作为纯度检测标记,采用单位点平均法统计4份常规棉品种检测结果表明,源棉6号纯度最高,为98.0%,源棉1号最低,为90.5%,检测结果与田间纯度鉴定呈现正相关性。研究表明利用SSR标记技术鉴定棉花品种真实性和纯度的方法完全可行。

Rapid Identification System of Purity and Authenticity in Cotton Varieties By SSR Markers

SSR molecular markers were used to analyze the authenticity and purity of cotton varieties, providing a molecular basis for the identification of cotton varieties. Typical cotton varieties were used as materials, and 26 pairs of primers well-distributed on the cotton genome were ascertained as the core primers in SSR molecular identification by preliminary and multiple screening. A total of 138 alleles from 120 varieties were screened by using 26 pairs of core primers, 129 of which were polymorphic loci, with a polymorphism rate of 93.48%. Ten inbred cotton varieties were used with 26 pairs of SSR core primers to identify the variety purity. The DNA fingerprint of one variety (Yuanmian 6) shared high uniformity with that of the standard cultivar, and DNA fingerprints of other nine varieties had 8–18 loci different from those of standard cultivar. The results from SSR molecular marker matched with those from field experiments. Five specific primers were selected for testing authenticity of each cultivar from 26 core primers. The variety with highest purity was Yuanmian 6, with the purity of 98.0% and that with lowest purity was Yuanmian 1, with the purity of 90.5%. It suggests that identifying authenticity and purity of cotton varieties is feasible by SSR molecular markers.