华北生态群普通杏遗传多样性与群体结构分析

Genetic Diversity and Population Structure of the North China Populations of Apricot (Prunus armeniaca L.)

【目的】研究华北生态群普通杏在不同地理来源间的遗传多样性、特异性和群体结构差异。【方法】应用21对SSR引物对67份华北生态群普通杏的遗传多样性和群体结构进行分析。【结果】21个SSR位点在67份华北生态群的普通杏材料中共检测出301个等位变异,每个位点的等位变异范围为8—24个,平均为14.33个。每个位点Shannon’s多样性指数(I)变异范围为0.65—2.67,平均为1.934。通过不同地理来源间比较,发现来自西北黄土高原区域的杏种质多样性丰富,拥有较多的等位变异。不同地理群间存在较多的互补等位变异;各地理群体拥有各自特有等位变异。基于混合模型的Structure2.2群体结构分析显示,将华北生态群普通杏划分为7个组群,且不同地理来源的材料均被划分到3个或以上的聚类群体。当K=4时,除仁用杏外华北生态群普通杏可以划分为西南亚群、华北平原亚群和东部丘陵亚群(包括山东丘陵地和辽南丘陵地的普通杏)3个亚群,与传统生态亚群划分相似。【结论】华北生态群普通杏种质具有丰富的遗传多样性,其中来自于西北地区的普通杏多样性最为丰富,有较多的变异类型。仁用杏种质遗传基础狭窄,但具有较多的特有等位变异和独特的血缘关系。华北生态群普通杏可以划分为3个亚群,但地理来源相同的种质不一定属于同一类群。

[Objective] The objective of the present study is to reveal the genetic diversity, specificity and population differentiation of the North China populations in common apricot （Prunus armeniaca L.）. [Method] A total of 21 simple sequence repeat （SSR） primers were used to detect the genetic variation, genetic diversity and population structure of 67 common apricots sampled from different regions. [Result] All of the 21 SSR loci were polymprphic among the 67 accessions and a total of 301 allelic variations were detected. The average number of allelic variations per locus was 14,33, ranging from 8 to 24. The average Shannon＇s information index （1） per locus was 1.934 with a range of 0.65-2.67. By comparison of the diversity among different origins, the genetic diversity of local apricot was rich in the northwest Loess Plateau region. More complementary alleles existed among different geographical origin types and specific alleles.existed among different geographical origin types. According to the model-based clustering method, seven groups in the North China populations were detected, and the accessions of different geographical origins were divided into three or more groups. When K--4, all the 63 tested genotypes （expect for kernel-using apricot） were divided into 3 populations： Southwestern group, North China Plain group and Eastern Hills group （Shandong and Southern of Liaoning）. This is similar to the traditional classification. [ Conclusion] A high level of genetic diversity was found in the North China population of common apricot.The most abundant genetic diversity was found in the population from the Northwest. The kemel-using apricot has a narrow genetic base, but has more specific alleles and unique ancestry source. The common apricot of the North China population can be divided into three subgroups, and the accessions from the same origin trends to be divided into the same group, with a few exception.