基于SSR标记的玉米循环群体选系材料的遗传基础分析

利用SSR标记技术对53份玉米循环群体选系材料和9个测验种进行分析,分析其遗传多样性,明确其遗传距离和杂种优势群划分,从分子遗传基础角度为循环育种策略奠定基础。结果表明,39个SSR标记在62份材料中共检测出162个等位基因变异,铁7922改良系和吉13S228改良系中分别检测出83、140个等位基因变异,位点多态性信息指数(PIC)平均分别为0.45、0.26、0.37;基因多样性指数平均分别为0.51、0.31、0.42;吉13S228改良系的遗传多样性高于铁7922改良系。遗传距离变幅在0.11~1.87,平均0.76;吉13S228改良系群体与吉13S228间的遗传距离最小(0.09),铁7922改良系群体与铁7922间的遗传距离亦较近(0.16),揭示改良系的遗传背景以改良受体为主。按照UPGMA聚类法、主成分分析和模型聚类方法,划分为两大类群,SS群(铁7922及其循环选系材料、B73、掖478等)和NSS群(吉13S228及其循环选系材料和标准测验种Mo17、丹340、黄早四等),符合玉米商业育种的两个杂种优势群的思路。

Genetic Base Analysis of Maize Inbred Lines from Recycling Selection by SSR Marker

SSR marker technology was used to analyze the selection materials and test species of 53 maize circulating populations. The results showed that a total of 162, 83, and 140 allelic variations were detected in 39 SSR markers in 62 materials, Tie7922 improved lines, and Ji13S228 improved lines, with an average of 4.05, 2.13, and 3.51. The point polymorphism information index(PIC) averaged 0.45, 0.26, and 0.37, respectively; the genetic diversity of the improved 13S228 improved line was higher than that of the Tie7922 improved line. The genetic distance ranged from 0.11-1.87, with an average of 0.76; the genetic distance between the 13S228 improved line group and Ji 13S228 was the smallest(0.09), and the genetic distance between the Tie7922 improved line group and the Tie7922 was also close(0.16). According to UPGMA clustering method, principal component analysis and model clustering method, it was divided into two groups:SS group(Tie7922 and its improved lines, B73, Ye478, etc.) and NSS group(Ji 13S228 and its improved lines and standard test lines Mo17, Dan 340 and Huangzao 4, etc.), which were in line with the idea of two heterosis groups in commercial maize breeding.