2009-2014年国家冬小麦区域试验品系的遗传多样性及群体结构分析

为了解我国小麦的育种水平、发展趋势及存在的问题,利用21对核心SSR标记对2009-2014年参加国家冬小麦区域试验的430个品系进行遗传多样性和群体结构分析.结果显示,21个SSR位点共检测到236个等位变异,平均每个位点11.24个,平均基因多样性和多态性信息量(PIC)分别为0.73和0.70;从不同年份分析,参试品系的遗传多样性从2012年开始略有下降;从不同生态种植区域分析,参试品系的遗传多样性自北向南(北部冬麦区组至长江流域冬麦区组)呈明显下降趋势;UPGMA聚类、主坐标和群体结构分析均表明,长江上游和长江中下游组的参试品系与其他区组的参试品系明显分开,且分别归属于不同亚类,显示出独特的生态区域类型;此外,群体结构分析结果还揭示,71.9％的参试品系群体结构比较单一,其中长江流域组的参试品系最为单一.

Genetic Diversity and Population Structure Analysis of Winter Wheat Lines from Recent National Regional Trials in China

To understand the wheat breeding level,development trend and existing problems,twenty-one core SSRs covering the entire wheat genome were used to analyze the genetic diversity and population structure of 430 winter wheat lines from national regional trials during 2009-2014 in China. 236 allelic variations were detected with an average allele number of 11.24. The average gene diversity values and PIC(Polymorphism information content) were determined as 0.73 and 0.70,respectively. Based on the analysis on different breeding years,genetic diversity decreased slightly since 2012. Based on the analysis from different appropriate growing regions,genetic diversity decreased gradually from north to south. UPGMA clustering,principal coordinate analysis(PCoA) and population structure analysis showed that the testing lines from the upper reaches of Yangtze river,the middle and lower reaches of the Yangtze river were obviously distinguished from other varieties of district group,and respectively belonged to different subpopulation,showing a certain degree of regional characteristic. In addition,population structure analysis also revealed that the population structure of 71.9% of the varieties was relatively simple,and that of varieties at the Yangtze river region was most simple.