Legume Genomics and Genetics 2025, Vol.16, No.2, 54-62 http://cropscipublisher.com/index.php/lgg 54 Research Insight Open Access Comparative Genomic Analysis of Wild and Cultivated Mung Bean (Vigna radiata) Yunxia Chen, Dan Luo, Hangming Lin Tropical Legume Research Center, Hainan Institute of Tropical Agricultural Resources, Sanya, 572025, Hainan, China Corresponding email: hangming.lin@hitar.org Legume Genomics and Genetics, 2025 Vol.16, No.2 doi: 10.5376/lgg.2025.16.0006 Received: 12 Jan., 2025 Accepted: 27 Feb., 2025 Published: 16 Mar., 2025 Copyright © 2025 Chen et al., This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: Chen Y.X., Luo D., and Lin H.M., 2025, Comparative genomic analysis of wild and cultivated mung bean (Vigna radiata), Legume Genomics and Genetics, 16(2): 54-62 (doi: 10.5376/lgg.2025.16.0006) Abstract Mung bean (Vigna radiata) is an important edible and forage legume crop and has a wide history of cultivation and consumption in Asia and other regions. Wild mung beans, as a close relative of cultivated mung beans, retain rich genetic diversity and are of great value for studying the domestication process and genetic improvement of mung beans. This study, based on whole-genome resequencing and comparative analysis, systematically analyzed the genomic structure, gene family evolution, genetic diversity and population structure of wild and cultivated mung beans. The results show that the genome of cultivated mung beans has undergone significant structural variations compared to the wild type, including the expansion and contraction of some gene families. Population genetic analysis indicates that mung beans experienced significant genetic bottlenecks during domestication, leading to a decline in SNP and InDel diversity in cultivated varieties. Meanwhile, comparative analysis revealed that a number of key genes related to flowering period, seed size, nutritional quality and stress resistance presented differential selection signals between wild and cultivated mung beans. Further gene function annotation and pathway analysis suggest that these genes may have played a significant role in the adaptive evolution and cultivation improvement of mung beans. This study established a genomic comparison framework between wild and cultivated mung beans, providing new evidence for understanding the domestication mechanism of legume crops and offering a strong reference for molecular breeding and genetic improvement of mung beans. Keywords Mung beans; Comparative genomics; Genetic diversity; Domestication; Molecular breeding 1 Introduction Mung beans (Vigna radiata), which might have originally been just a wild plant somewhere in South Asia, have now become common legumes on dining tables in many regions, especially being widely consumed in Asia and Africa. It can not only be made into dry food and tender sprouts, but is also often used in traditional herbs. What is most valued about this plant is not only its fast growth and short cycle, but also its ability to fix nitrogen, which is very helpful for soil improvement and crop rotation. In addition, it can adapt to various climates and is quite drought-resistant. In terms of food security in developing countries, it plays a certain key role to some extent (Wu et al., 2020; Mwangi et al., 2021; Rohilla et al., 2022; Huppertz et al., 2023). When it comes to nutrition, mung beans themselves are no less impressive. The protein content in their dry seeds can reach 24%-27%, and they are also rich in various essential amino acids, iron, folic acid and other trace elements. Cultivated mung beans and their ancestors, the wild subspecies V. radiata var. sublobata, have already developed a considerable genetic gap. This kind of differentiation does not occur entirely naturally; most of it is caused by human activities. To meet the demands of agriculture, people prefer traits that are early-maturing, high-yielding and less prone to podding. However, precisely because of these choices, the genetic basis of mung beans has narrowed (Liu et al., 2022; Huppertz et al., 2023; Jia et al., 2024). In other words, some traits that were considered "useful" were retained, but many other genetic resources were thus left aside. Comparative genomics technology comes in handy here. It can not only draw the genetic map of mung beans, but more importantly, it can help researchers identify genes related to key traits, such as loci related to flowering, disease resistance or nutrition. In recent years, whether it is the assembly of high-quality genomes, the alignment of pan-genomes, or genome-wide association studies such as GWAS, all have been used to screen out these candidate genes (Ha and Lee, 2019;
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