利用SSR标记分析27个玉米群体的遗传关系

本研究采用SSR标记技术，通过混合取样法分别从每个群体中随机提取4个样本，每个样本由10个单株混合而成，分析了国内外27个玉米群体的遗传多样性。结果表明：71对引物在27 个群体中共扩增出389个等位位点，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的群体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。

The Genetic Diversity Among 27 Maize Populations Based on SSR Data

The genetic diversity among 27 maize ( Zea mays L. ) populations has been analyzed based on the data of SSRs, which were from 4 bulk DNA samples for each population and 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. On the 71 SSR loci, a total of 389 alleles had been 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. There was nearly no difference in the proportion of polymorphic sites between domestic and CIMMYT populations, which were 92.5 for domestic and 92.2% for CIMMYT populations. 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: group 1 was of CIMMYT germplasm including: Pob21, Pob32, Stay Green, Pob43, Pob49, Pool19, Pob28, Pob45, Pob46, Pob501, Pob502, and Suwan1. Group 2 was of domestic and temperate adaptive populations including : Jilin Syn A, Liaolv Syn, CSyn 5, CSyn3, CSyn4, Yu Syn5, Golden Queen, Shaan Syn1, Shaan Syn3, Dongnong Pop C5, WBM-C4, CPop13, CPop14, Pob69, and Pob70. The results basically were agreeable with the available pedigree data.