State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, College of Agriculture, Henan University, Kaifeng, Henan 475004, China.
State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
J Genet Genomics. 2022 Mar;49(3):185-194. doi: 10.1016/j.jgg.2021.11.004. Epub 2021 Nov 24.
Aegilops tauschii, the wild progenitor of wheat D-genome and a valuable germplasm for wheat improvement, has a wide natural distribution from eastern Turkey to China. However, the phylogenetic relationship and dispersion history of Ae. tauschii in China has not been scientifically clarified. In this study, we genotyped 208 accessions (with 104 in China) using ddRAD sequencing and 55K SNP array, and classified the population into six sublineages. Three possible spreading routes or events were identified, resulting in specific distribution patterns, with four sublineages found in Xinjiang, one in Qinghai, two in Shaanxi and one in Henan. We also established the correlation of SNP-based, karyotype-based and spike-morphology-based techniques to demonstrate the internal classification of Ae. tauschii, and developed consensus dataset with 1245 putative accessions by merging data previously published. Our analysis suggested that eight inter-lineage accessions could be assigned to the putative Lineage 3 and these accessions would help to conserve the genetic diversity of the species. By developing the consensus phylogenetic relationships of Ae. tauschii, our work validated the hypothesis on the dispersal history of Ae. tauschii in China, and contributed to the efficient and comprehensive germplasm-mining of the species.
节节麦，小麦 D 基因组的野生近缘祖先，也是改良小麦的宝贵种质资源，其在自然环境中的分布范围很广，从土耳其东部一直延伸到中国。然而，节节麦在中国的系统发育关系和扩散历史尚未得到科学的阐明。在本研究中，我们使用 ddRAD 测序和 55K SNP 芯片对 208 个节节麦材料（其中 104 个来自中国）进行了基因型分析，并将该群体分为六个亚系。鉴定出了三个可能的扩散途径或事件，导致了特定的分布模式，其中四个亚系分布在新疆，一个在青海，两个在陕西，一个在河南。我们还建立了 SNP 分型、染色体核型分型和穗型形态学分型技术之间的相关性，以证明节节麦的内部分类，并通过合并之前发表的数据，开发了一个包含 1245 个假定材料的共识数据集。分析表明，八个种间材料可以被归为假定的第 3 亚系，这些材料有助于保护该物种的遗传多样性。通过建立节节麦共识系统发育关系，我们的工作验证了节节麦在中国的扩散历史假说，并有助于该物种的高效和全面的种质挖掘。
