Feed and Forage Development Program, International Livestock Research Institute, Addis Ababa P.O. Box 5689, Ethiopia.
The Pacific Community (SPC), Private Mail Bag, Suva, Fiji.
Genes (Basel). 2021 Aug 10;12(8):1233. doi: 10.3390/genes12081233.
Rhodes grass ( Kunth) is one of the most important forage grasses used throughout the tropical and subtropical regions of the world. Enhancing the conservation and use of genetic resources requires the development of knowledge and understanding about the existing global diversity of the species. In this study, 104 Rhodes grass accessions, held in trust in the ILRI forage genebank, were characterized using DArTSeq markers to evaluate the genetic diversity and population structure, and to develop representative subsets, of the collection. The genotyping produced 193,988 SNP and 142,522 SilicoDArT markers with an average polymorphic information content of 0.18 and 0.26, respectively. Hierarchical clustering using selected informative markers showed the presence of two and three main clusters using SNP and SilicoDArT markers, respectively, with a cophenetic correction coefficient of 82%. Bayesian population structure analysis also showed the presence of two main subpopulations using both marker types indicating the existence of significant genetic variation in the collection. A representative subset, containing 21 accessions from diverse origins, was developed using the SNP markers. In general, the results revealed substantial genetic diversity in the Rhodes grass collection, and the generated molecular information, together with the developed subset, should help enhance the management, use and improvement of Rhodes grass germplasm in the future.
皇竹草（Kunt h）是世界热带和亚热带地区最重要的牧草之一。为了加强对遗传资源的保护和利用，需要了解该物种现有的全球多样性。本研究利用 DArTSeq 标记对 ILRI 牧草基因库中保存的 104 份皇竹草种质进行了特征分析，以评估该收集品系的遗传多样性和群体结构，并开发出具有代表性的子集。基因分型产生了 193988 个 SNP 和 142522 个 SilicoDArT 标记，平均多态信息含量分别为 0.18 和 0.26。使用选定的信息标记进行的层次聚类显示，SNP 和 SilicoDArT 标记分别存在两个和三个主要聚类，其协方差校正系数分别为 82%。基于标记类型的贝叶斯种群结构分析也表明存在两个主要亚群，这表明该收集品系存在显著的遗传变异。使用 SNP 标记开发了一个包含 21 份来自不同起源的代表性子集。总体而言，研究结果表明皇竹草收集品系具有丰富的遗传多样性，所产生的分子信息以及开发的子集应有助于未来加强对皇竹草种质的管理、利用和改良。
