中文摘要：

[目的]分析27个CIMMYT玉米群体和中国玉米群体的遗传多样性及其之间的遗传关系,为玉米种质的扩增与改良提供依据.[方法]利用SSR标记技术和DNA混合取样方法,选取均匀覆盖玉米染色体组的71对SSR引物对样品进行PCR扩增分析.[结果]71对引物在27个群体中共扩增出389个等位基因,每个SSR位点的等位基因数为2～19个,平均为5.48个;平均多态性信息量为0.66,变化范围0.27～0.92.来自CIMMYT群体的多态性位点总数比国内适应群体的略高,但其多态性位点比例基本相同.根据27个群体的108个样本的遗传相似系数矩阵做出树型图,把27个群体大体分成了国内和国外两大群6个亚群.[结论]热带、亚热带玉米种质含有更多的特有基因,导入热带、亚热带玉米种质可扩增温带玉米种质基础,聚类结果与系谱基本吻合.

英文摘要：

[Objective] In this study, the genetic diversity and relationship among 27 maize （Zea mays L. ） populations were analyzed based on the data of SSRs. [Method] Four bulk DNA samples for each population were extracted from leaf mixture of 10 individuals for each sample. The genetic diversity of 27 maize populations, including 13 domestic and 14 CIMMYT populations were evaluated by 71 SSR primers, which are averagely distributed on 10 chromosomes of maize. [ Result ] On the 71 S SR loci, a total of 389 alleles were detected in these populations. At each locus, 2 to 19 alleles could be detected, with an average of 5.48. Mean polymorphism information content was 0.66. The number of polymorphic alleles differed in domestic and CIMMY populations, which were 329 for domestic populations and 370 for CIMMYT populations. Cluster analysis was based on the genetic similarity coefficients. Two heterotic groups were determined among the 27 populations. [Conclusion] There were more special＇genes in tropical and subtropical germplasm than temperate germpalsm. Temperate germplasm can be enhanced by introducing tropical and subtropical germpalsm. The results basically are agreeable to the available pedigree data.