分析中国栽培大豆遗传多样性所需SSR引物的数目

Identification of SSR Primer Numbers for Analyzing Genetic Diversity of Chinese Soybean Cultivated Soybean

我国拥有极其丰富的大豆资源 ,传统的方法是根据农艺性状来分析其遗传变异 ,但农艺性状受自然环境和人为因素影响明显。随着大豆育成品种的增加 ,有限的表型变异已难以详细阐明我国 2万余份大豆品种的遗传变异情况 ,需要从DNA分子水平深入研究我国大豆资源遗传变异分布规律。本研究以 190份为大豆为初选核心种质的一个无偏样本 ,用 6 0对SSR引物扩增 ,获得 6 0 6个等位变异 ,平均每个位点有 10个等位变异 ,位点多态信息量范围从 0 5 5到 0 99,平均为 0 83。对 190份大豆相似系数矩阵的标准误分析表明 ,SSR引物数增加到 5 0左右时 ,再增加引物 ,标准误变化很小。共表型矩阵之间的相关性测验显示 ,当等位变异数达到 5 70以上 ,相互之间相关性极显著。从实验材料中选取东北春大豆类型作为一个小样本进行共表型矩阵相关性分析也有类似结果。用SSR方法分析中国栽培大豆 (G max)遗传变异关系时 ,只有等位变异数达到一定的范围时 ,才能真实地反映出品种之间的遗传变异关系。当群体的遗传变异范围变得相对较小时 ,分析个体之间的遗传变异关系所需的等位变异数目也相应降低。结合SSR位点在大豆基因组中的分布和基因多样性水平 ,能够找到分析栽培大豆遗传多样性的核心SSR引物。只有获得等位变异数在 5 70以上 ,

The traditional way was applied to define genetic diversity of abundant Chinese soybean accessions according to agronomic traits, but those traits were affected by environmental and unnatural factors Genetic diversity of soybean germplasmand resources should be further studied from the DNA level because phenotype traits had not enough to expound their relationships among over 20,000 genotypes with cultivars increased 190 experimental materials were a standard sample obtained from Chinese soybean primary core collection 606 alleles were found in 60 loci, with each locus having a mean of 10 alleles, and the mean of gene diversity scores was 0 83, with a range of 0 55～0 99 Standard error of similarity matrices was analyzed with SSR primers increased, and the change of standard error appeared few fluctuations after the number of SSR loci reached 50 The correlation among cophenetic matrices was also examined using Mantel correlation test There was good fit among those matrices if alleles raised over 570 Analyzing the correlation of cophenetic matrices originated from a small sample of North East Spring Planting Soybean from experimental materials showed the similar results The truly genetic relationship of Chinese soybean cultivars (G max) could be obtained from enough alleles using SSR markers The scope of genetic diversity was reduced to a relatively smaller range, and the number of alleles used to study relationships among accessions became correspondently fewer The core SSR primers might be selected according to distribution of the SSR loci in the soybean genome and gene diversity scores The objectively genetic relationships of Chinese soybean cultivars could be reflected using over 570 alleles