ICAR-National Research Centre on Plant Biotechnology, New Delhi, India.
ICAR-Central Arid Zone Research Institute (CAZRI), Jodhpur, India.
Gene. 2019 Jul 30;707:205-211. doi: 10.1016/j.gene.2019.02.090. Epub 2019 Mar 18.
Clusterbean (C. tetragonoloba) is an important, leguminous vegetable and industrial crop with vast genetic diversity but meager genetic, cytological and genomic information. In the present study, an optimized procedure of flow cytometry was used to estimate the genome size of three clusterbean species, represented by C. tetragonoloba (cv. RGC-936) and two wild relatives (C. serreta and C. senegalensis). For accurate estimation of genomic content, singlet G/G populations of multiple tissues such as leaves, hypocotyl, and matured seeds were determined and used along with three different plant species viz. Pisum sativum (as primary), Oryza sativa, and Glycine max (secondary), as external and internal reference standards. Seed tissue of the test sample and G. max provided the best estimate of nuclear DNA content in comparison to other sample tissues and reference standards. The genome size of C. tetragonoloba was detemined at 580.9±0.02Mbp (1C), while that of C. serreta and C. senegalensis was estimated at 979.6±0.02Mbp (1C) and 943.4±0.03Mbp (1C), respectively. Thus, the wild relatives harbor, nearly double the genome content of the cultivated cluster bean. Findings of this study will enrich genomic database of the legume family and can serve as the starting point for clusterbean evolutionary and genomics studies.
兵豆（C. tetragonoloba）是一种重要的豆科蔬菜和工业作物，具有广泛的遗传多样性，但遗传、细胞和基因组信息却很少。在本研究中，采用优化的流式细胞术程序，估算了三种兵豆物种（代表品种为 RGC-936 以及两个野生近缘种 C. serreta 和 C. senegalensis）的基因组大小。为了准确估计基因组含量，确定了叶片、下胚轴和成熟种子等多种组织的单峰 G/G 群体，并与豌豆（作为初级标准）、水稻和大豆（作为次级标准）三种不同植物物种一起使用。与其他组织和参考标准相比，测试样本的种子组织和大豆提供了核 DNA 含量的最佳估计值。兵豆的基因组大小为 580.9±0.02Mbp（1C），而 C. serreta 和 C. senegalensis 的基因组大小分别估计为 979.6±0.02Mbp（1C）和 943.4±0.03Mbp（1C）。因此，野生近缘种的基因组含量几乎是栽培兵豆的两倍。本研究的结果将丰富豆科植物基因组数据库，并可为兵豆进化和基因组学研究提供起点。
