中国88个马铃薯审定品种SSR指纹图谱构建与遗传多样性分析

为对马铃薯品种鉴别、优良杂交组合选配提供分子水平上的依据，利用SSR标记构建了中国2000—2007年审定的88个马铃薯品种的指纹图谱并进行了遗传多样性分析。以138对SSR引物对16份遗传差异较大的马铃薯材料的基因组DNA进行了扩增，筛选出10对多态性高、谱带清晰的引物。利用10对SSR引物对全部供试材料进行扩增及电泳检测，共检测到135个等位位点，其中133个为多态性位点，多态性比率达98.52%。每对SSR引物扩增出的等位位点数7~22个，平均13.5个，多态性信息量变化范围为0.7604~0.9375，平均0.8501。通过对电泳检测结果的统计分析，利用S180、S25、S7、S151、S184及S192等6对引物构建了88份供试材料的SSR指纹图谱。聚类分析表明，在相似系数0.620处，所有供试材料被被聚为一类，在相似系数0.652处，81.8%的材料仍然聚在一起，从分子水平上表明供试材料遗传基础非常狭窄。聚类分析结果与供试材料系谱来源有较好一致性，同一栽培区域育成的品种在不同程度上聚在一类。

Construction of Fingerprinting and Analysis of Genetic Diversity with SSR Markers for Eighty-Eight Approved Potato Cultivars (Solanum tuberosum L.) in China

Potato (Solanum tuberosum L.) is one of the most important food crops in the world. Approved potato cultivars have contributed a lot not only to potato production but also to varietal improvement as germplasm resource, and about 110 potato cultivars were approved during 2000–2007 in China. It is necessary to make potato cultivar identification and genetic relationship analysis for seed production, germplasm management, plant variety protection and breeding practice. Currently, the simple sequence repeats (SSRs) are preferred as molecular markers due to their highly desirable properties. In this study, for the aim of cultivar identification and parents combination at the molecular level, SSR markers were employed to analysis on fingerprinting and genetic diversity of 88 potato cultivars approved in China during 2000–2007. Ten of one hundred and thirty-eight pairs of SSR primers were screened out based on sixteen accessions distinct in genetics. The 10 primer pairs amplified a total of 135 alleles (including 133 polymorphic alleles) among the 88 cultivars, and the ratio of polymorphism was as high as 98.52%.Alleles amplified by each pair of primers ranged from 7 (primer S7) to 22 (primer S189), with a mean of 13.5. The polymorphic information content values (PIC) ranged from 0.7604 (primer S192) to 0.9375 (primer S189), with a mean of 0.8501. The fragment sizes varied from 80 to 380 bp. The fingerprinting of 88 cultivars was constructed by 6 pairs of primers of S180, S25, S7, S151, S184, and S192. Eighty-seven out of eighty-eight cultivars were univocally identified by using only five SSR primers (S180, S25, S7, S151, and S184). UPGMA cluster analysis of genetic similarity showed that all the materials were clustered in to one group at the genetic similarity of 0.620, and 81.8% of the cultivars were still clustered together at the genetic similarity of 0.652.The genetic relationships of cultivars were identical to the family tree basically. It’s indicated that the genetic basis of potato cultivars in China is narrow, and the genetic relationship of the potato cultivars derived from the same district is similar. Thefingerprinting and analysis of genetic diversity in this studygave a basis for exploration and utilization of approved potato cultivars as germplasm resources.