摘 要 ：全面了解西南地区小麦抗条锈病种质遗传多样性和群体结构信息，能有效提高抗病品种的育种效率。在本研究中，我们利用基于基因分型测序（GBS）技术的DArT-seqTM方法对134份小麦材料开展了全基因组基因分型，共获得了6919个多态性的SNP（single nucleotide polymorphism）标记。它们的多态性指数（PIC，polymorphism information content）的范围在0.01到0.50之间，平均值为0.32。根据SNP标记在134份小麦品种中的基因分型数据，计算了品种间的遗传相似系数（GS），其变异范围为 0.51～0.98，平均值0.61。非加权组平均法（UPGMA，unweighted pair-group method with arithmetic mean）聚类分析结果显示根据来源地和亲缘关系的不同，这批小麦品种（系）可划分为五个群。主坐标分析（PCoA）结果显示，小麦材料清晰地聚集形成了两个群。第一类群由不同来源的小麦材料组成，群体较大且分布更紧密。而第二类群几乎都由贵州小麦组成，品种数目较少但更加分散。在抗条锈病基因的分布上，大多数携带Yr9基因位点的小麦品系聚集在第一类群中，而绝大多数携带Yr26抗病基因位点的小麦品系则聚集在第二类群中。本研究从基因型多样性水平上阐释了西南地区小麦抗病种质遗传背景，为西南地区和我国小麦的抗条锈病育种的提供了理论依据。
Abstract:Knowledge of genetic diversity and population structure is essential for the effective use of wheat germplasms resistant to stripe rust in southwest China in breeding programs. In this study, DArT-seqTM based on genotyping by sequencing (GBS) approach was used to screen a collection of 134 common wheat varieties from the whole genome, and 6919 informative single nucleotide polymorphism (SNP) markers were obtained. The polymorphism information content (PIC) of SNP markers was in the range from 0.01 to 0.50, with the average of 0.32. SNP-based genetic similarity (GS) value among 134 wheat accessions ranged from 0.51 to 0.98, with the average of 0.61. The unweighted pair-group method with arithmetic mean (UPGMA) dendrogram indicated that the wheat accessions were clustered into five groups according to their origins and pedigrees. Two clear groups (Group I and Group II) were identified using principal-coordinates analysis (PCoA) of the whole-genome level. Group I is highly clustered with no obvious separation of cultivars (lines) originating from different geographic regions, most of them carried Yr9 locus; Group II was mainly composed of varieties from Guizhou province, most of them carried Yr26 locus. Our results provide valuable information of genetic diversity for stripe rust resistant wheat germplasms in Southwest China, which will facilitate wheat breeding for resistance to strip rust in our country.