111份大薯种质资源遗传多样性AFLP分析

Genetic Diversity of 111 Dioscorea alata Linn. Germplasms Using AFLP Markers

采用AFLP分子标记方法对收集于6省不同地区的111份大薯种质资源进行遗传多样性分析。筛选到的8个AFLP引物组合扩增到1291个位点，其中1286个是多态性位点。利用多态性信息含量（PIC）、标记指数（MI）和解析强度（RP）分析不同引物组合的标记效率，获得引物的 PIC平均值为 0.22，MI平均值为35.67，RP平均值为50.50，表明引物扩增位点的高多态性和对大薯种质资源具有强辨别能力，其中引物E-AAC/CAG-M（PIC 0.24、MI 38.56、 RP 56.32）具有较高的标记效率。111份大薯种质的遗传相似系数（GS）在0.30～0.82之间，平均为0.58，表明大薯种质资源的遗传相似性较低。采用UPGMA对大薯种质进行聚类分析，遗传相似系数在0.54时，111份材料被划分为4个类群和3个单独的分支（序号分别为20、42、47），不同地区来源的大薯材料在聚类图中没有明显界限。

Amplified Fragment Length Polymorphisms（AFLP） analysis was employed to reveal the genetic diversity of Dioscorea alata Linn.. 111 germplasm, collected from six different provinces of China, were used with eight AFLP primer combinations that generated a total of 1291 fragments. A total of 1286 fragments showed polymorphism in the germplasm analyzed. A variety of marker attributes like polymorphism information content （PIC）, marker index （MI） and resolving power （RP） values were calculated to assess the discriminatory power of eight primer combinations. The average values of PIC （0.22）, MI（35.67）, and RP （50.50） indicated great polymorphic and distinguishable ability of the eight AFLP primer combinations. The primer combination E-ACT/M-CTTE-AAC/CAG-M was be most informative with PIC, MI,and RP being 0.22, 35.67, 50.50, respectively. A total of 1286 fragments presented polymorphism which can be summaried as great divesity among 111 Dioscorea alata Linn. germplasm with extremely lower similiary （0.30 to 0.82 with average of 0.58） germplasm. At the genetic similarity coefficient level of 0.54, the unweighted pair group method with arithmetic mean （UPGMA） phylogentic anlaysis further classified those gemplasm into four subcroups, and the germplasm 20, 42 and 47 were individually separated. The clustering results indicate no close relation to the geographic location of the germplasm.