糜子EST-SSR分子标记的开发及种质资源遗传多样性分析

基于前期高通量测序结果设计EST-SSR引物, 用于评估国内外不同生态区144份糜子(Panicum miliaceum)种质资源的遗传差异。结果表明, 200对引物中80对呈多态性, 开发效率为40%; 引物分辨率(Rp)为0.67-4.67 (平均值为2.00), 扩增产物大小为50-500 bp。144份材料在80个位点共检测到206个等位变异, 每个位点为2-3个; 多样性指数(I)为0.659 3 (RYW108)-1.087 2 (RYW124), 平均为0.859 9; 多态性信息含量(PIC)为0.222 9 (RYW98)-0.717 2 (RYW124), 平均为0.457 3。基于UPGMA将144份资源划分为3个群组, 其中2个群组主要为北方春糜子区材料, 另一个群组主要为黄土高原春夏糜子区材料。基于Structure (K=4)将材料划分为4个类群, 即2个代表北方资源基因库以及代表黄土高原和国外资源基因库各1个。基于主成分分析将材料聚为7个类群, 划分结果与材料的地理来源一致。

The Genetic Diversity of Common Millet (Panicum miliaceum) Germplasm Resources Based on the EST-SSR Markers

The EST-SSR molecular markers of common millet (Panicum miliaceum) were developed by high-throughput sequencing. Using these markers, we assessed the genetic diversity in a panel of 144 common millet accessions collected from different ecotopic regions in China and abroad. It was shown that 80 pairs of these markers were polymorphic, with the efficiency of approximately 40%. The resolution power (Rp) was 0.67-4.67 (mean 2.00) and the amplified product sizes ranged from 50 to 500 bp. Among the examined 144 accessions, 206 allelic variations were identified in 80 loci, with 2-3 alleles at each locus. The Shannon’s diversity index (I) ranged from 0.659 3 (RYW108) to 1.087 2 (RYW124) with an average of 0.859 9. The range of polymorphism information content (PIC) was 0.222 9 (RYW98) -0.717 2 (RYW124) with an average of 0.457 3. Based on UPGMA, these 144 accessions were classified into 3 groups, two of which belonged to the the Northern China spring-sowing ecotopes and one group was mainly from the Loess Plateau spring-summer-sowing ecotopes. Based on Structure (K=4), all the accessions were divided into four groups, of which two groups represented the gene pool originated from the Northern China, whereas the other two groups from the Loess Plateau and abroad accessions. Based on principal component analysis (PCA), the accessions were clustered into seven groups, consistent with their geographic origins.