基于QTL相关SSR标记分析黄淮海和南方大豆品种的遗传多样性及群体遗传结构

Population structure and genetic analysis within soybean cultivars of Huang-Huai-Hai and Southern region of China based on SSR markers related to QTL

研究大豆育成品种遗传多样性及群体结构对大豆遗传改良具有重要的指导意义。本文利用99个与大豆QTL性状相关的SSR标记,对黄淮海和南方产区的105份大豆育成品种进行遗传多样性和群体结构分析。结果表明:99个位点共检测出1142个等位标记,每个位点变异范围为5~24个,平均每个位点11.54个等位变异。按品种育成时期将群体划分为4个亚群,亚群内Nei’s基因多样性范围0.628~0.839,平均0.774。多态性信息含量范围0.562~0.820,平均0.742。亚群间Nei’s遗传距离范围0.387~0.197,平均0.297。分子方差分析表明大豆材料99%为亚群内变异,仅1%为亚群间变异,说明不同时期内大豆材料之间交流频繁。主坐标分析的三个主成分分别解释了4.12%、3.61%和2.90%的总变异。UPGMA聚类和群体遗传结构分析都将大豆材料划分为3个类群,且结果高度一致,而且与大豆育成品种在主要家族系谱中代数及各时期亚群的遗传基础相关。大豆育成品种遗传多样性水平具有一定的时期特征,其总体水平呈递增趋势。

Research of the population structure and genetic diversity has guiding significance to soybean improvement. In this study, 105 cultivar soybean accessions bred from Huang-Huai-Hai and Southern region of China were collected to detect their population structure and genetic diversity by using 99 SSR polymorphic primer pairs.The results showed that a total of 1142 alleles were detected at 99 loci with 11.54 average number of alleles per locus ranging from 5 to 24. The whole population was divided into 4 subgroups according to breeding period. The range of Nei’s gene diversity was 0.628-0.839 with an average of 0.774. The polymorphism information content ranged from 0.562-0.820 with an average of 0.742. The genetic distance between subgroups ranged from 0.387 to0.197 with an average of 0.297. Ninety-nine percentage of total variation was explained within the subgroups,and1% of total variation was explained among subgroups based on the molecular variation analysis, which indicated that there were frequent gene exchanges in subgroups. The principal coordinate analysis showed that the first, second, and third principal factors explained 4.12%, 3.61%, and 2.90% of the total variation respectively. These soybean germplasm could be divided into 3 subgroups based on STRUCTURE analysis and unweighted pair group method with arithmetic average(UPGMA) cluster. Further comparison showed that the UPGMA subgroups and STRUCTURE subgroups displayed a highly consistent correlation with these pedigrees and the genetic base of each period. The genetic diversity had period characteristics and showed an increasing trend in this study.