小麦周8425B及其衍生品种与黄淮麦区主栽品种的遗传解析

为了解小麦骨干亲本周8425B及其衍生品种与黄淮麦区主栽品种的遗传结构和遗传多样性,利用Illumina 90KiSelect SNP标记技术对周8425B及其16份衍生品种和23份黄淮麦区主栽品种进行全基因组扫描。结果显示,在40份小麦材料中,有22 466个多态性SNP位点被定位在21条染色体上,不同基因组间多态性SNP标记的分布依次为BAD。周8425B及其衍生品种的遗传相似系数变化范围为0.640 5~0.926 4,平均值为0.739 8,与黄淮麦区主栽品种间遗传差异较小。供试材料的遗传相似系数变化范围为0.530 1~0.963 4,平均值为0.672 1,并被划分为4个类群,聚类分析结果与系谱较为吻合。周8425B对其衍生一代、二代、三代的平均贡献率为79.48%、76.73%和74.24%,随世代的增加而不断降低,且在不同基因组间的遗传贡献率表现为DAB。全基因组扫描结果显示,周8425B衍生品种共有6 789个SNP位点保留了周8425B的遗传基因,不同基因组继承的SNP位点数不同,依次为BAD,这些选择位点可能与重要基因的遗传传递有关,可能是周8425B成为骨干亲本的主要遗传特征。

Genetic Dissection on the Derived Lines from Wheat Cultivar Zhou 8425B and Widely Grown Cultivars in Huang-huai Region

The common wheat Zhou 8425B is an important core wheat parent in Huang-huai wheat region. In order to define the genetic structure and diversity of Zhou 8425B and its offspring, thus provide information and contribute to the future wheat breeding improvement,23 widely grown varieties in Huang-huai region and 16 derivative varieties of Zhou 8425B were genotyped with the 90K SNP array based on the infinium assay. The total of 22 466 SNPs with polymorphism spread on 21 chromosomes were detected among the 40 varieties and the polymorphic SNPs showed a distribution tendency of B>A>D among different genomes. The genetic similarity of the core parent Zhou 8425B and its derivative varieties ranged from 0.640 5 to 0.926 4 with an average value of 0.739 8. However, the genetic similarity of 0.530 1 to 0.963 4 with an average value of 0.672 1 was found between widely grown varieties in Huang-huai region and derivative varieties of Zhou 8425B, indicating that they have high similarity in genetic background. The 40 varieties could be classified into four groups by clustering analysis which was generally agreed with the pedigree analysis. The results of the genetic contribution of Zhou 8425B to its derivatives varieties indicated that Zhou 8425B had the contribution ratios of 79.48%, 76.73% and 74.24% to its first, second and third generations, respectively, which was decreased from generation to generation. The average genetic contribution of A, B and D genomes were in decreasing order of D>A>B. The SNP genotyping results showed that the derivative varieties of Zhou 8425B preserved 6789 SNPs loci which were derived from their shared parent Zhou 8425B and these SNPs loci were distributed in order as B>A>D among different genomes and these conserved SNPs loci could be connected with important agronomic traits in Zhou 8425B. This might be basic genetic features of Zhou 8425B as a founder parent.