Chiteri Kevin O, Jubery Talukder Zaki, Dutta Somak, Ganapathysubramanian Baskar, Cannon Steven, Singh Arti
Department of Agronomy, Iowa State University, Ames, IA, United States.
Department of Mechanical Engineering, Iowa State University, Ames, IA, United States.
Front Plant Sci. 2022 Jan 27;12:808001. doi: 10.3389/fpls.2021.808001. eCollection 2021.
Mung bean [ (L.) Wilczek] is a drought-tolerant, short-duration crop, and a rich source of protein and other valuable minerals, vitamins, and antioxidants. The main objectives of this research were (1) to study the root traits related with the phenotypic and genetic diversity of 375 mung bean genotypes of the Iowa (IA) diversity panel and (2) to conduct genome-wide association studies of root-related traits using the Automated Root Image Analysis (ARIA) software. We collected over 9,000 digital images at three-time points (days 12, 15, and 18 after germination). A broad sense heritability for days 15 (0.22-0.73) and 18 (0.23-0.87) was higher than that for day 12 (0.24-0.51). We also reported root ideotype classification, i.e., PI425425 (India), PI425045 (Philippines), PI425551 (Korea), PI264686 (Philippines), and PI425085 (Sri Lanka) that emerged as the top five in the topsoil foraging category, while PI425594 (unknown origin), PI425599 (Thailand), PI425610 (Afghanistan), PI425485 (India), and AVMU0201 (Taiwan) were top five in the drought-tolerant and nutrient uptake "steep, cheap, and deep" ideotype. We identified promising genotypes that can help diversify the gene pool of mung bean breeding stocks and will be useful for further field testing. Using association studies, we identified markers showing significant associations with the lateral root angle (LRA) on chromosomes 2, 6, 7, and 11, length distribution (LED) on chromosome 8, and total root length-growth rate (TRL_GR), volume (VOL), and total dry weight (TDW) on chromosomes 3 and 5. We discussed genes that are potential candidates from these regions. We reported beta-galactosidase 3 associated with the LRA, which has previously been implicated in the adventitious root development transcriptomic studies in mung bean. Results from this work on the phenotypic characterization, root-based ideotype categories, and significant molecular markers associated with important traits will be useful for the marker-assisted selection and mung bean improvement through breeding.
绿豆[（L.）威尔茨克]是一种耐旱的短周期作物，富含蛋白质以及其他有价值的矿物质、维生素和抗氧化剂。本研究的主要目的是：（1）研究与爱荷华州（IA）多样性面板中375个绿豆基因型的表型和遗传多样性相关的根系性状；（2）使用自动根系图像分析（ARIA）软件对根系相关性状进行全基因组关联研究。我们在三个时间点（发芽后第12天、15天和18天）收集了9000多张数字图像。第15天（0.22 - 0.73）和第18天（0.23 - 0.87）的广义遗传力高于第12天（0.24 - 0.51）。我们还报告了根系理想型分类，即PI425425（印度）、PI425045（菲律宾）、PI425551（韩国）、PI264686（菲律宾）和PI425085（斯里兰卡）在表土觅食类别中排名前五，而PI425594（来源不明）、PI425599（泰国）、PI425610（阿富汗）、PI425485（印度）和AVMU0201（台湾）在耐旱和养分吸收“陡、廉、深”理想型中排名前五。我们鉴定出了有前景的基因型，这些基因型有助于使绿豆育种材料的基因库多样化，并将用于进一步的田间试验。通过关联研究，我们在2号、6号、7号和11号染色体上鉴定出了与侧根角度（LRA）显著相关的标记，在8号染色体上鉴定出了与长度分布（LED）显著相关的标记，在3号和5号染色体上鉴定出了与总根长生长速率（TRL_GR）、体积（VOL）和总干重（TDW）显著相关的标记。我们讨论了这些区域中潜在的候选基因。我们报告了与LRA相关的β - 半乳糖苷酶3，此前在绿豆不定根发育转录组研究中已涉及该酶。这项工作在表型特征、基于根系的理想型类别以及与重要性状相关的显著分子标记方面的结果，将有助于标记辅助选择和通过育种改良绿豆。
