Genome-Wide SNP Identification and Association Mapping for Seed Mineral Concentration in Mung Bean (Vigna radiata L.)

Mung bean (Vigna radiata L.) quality is dependent on seed chemical composition, which in turn determines the benefits of its consumption for human health and nutrition. While mung bean is rich in a range of nutritional components, such as protein, carbohydrates and vitamins, it remains less well studied than other legume crops in terms of micronutrients. In addition, mung bean genomics and genetic resources are relatively sparse. The objectives of this research were three-fold, namely: to develop a genome-wide marker system for mung bean based on genotyping by sequencing (GBS), to evaluate diversity of mung beans available to breeders in the United States and finally, to perform a genome-wide association study (GWAS) for nutrient concentrations based on a seven mineral analysis using inductively coupled plasma (ICP) spectroscopy. All parts of our research were performed with 95 cultivated mung bean genotypes chosen from the USDA core collection representing accessions from 13 countries. Overall, we identified a total of 6,486 high quality single nucleotide polymorphisms (SNPs) from the GBS dataset and found 43 marker × trait associations (MTAs) with calcium, iron, potassium, manganese, phosphorous, sulfur or zinc concentrations in mung bean grain produced in either of two consecutive years’ field experiments. The MTAs were scattered across 35 genomic regions explaining on average 22% of the variation for each seed nutrient in each year. Most of the gene regions provided valuable candidate loci to use in future breeding of new varieties of mung bean and further the understanding of genetic control of nutritional properties in the crop. Other SNPs identified in this study will serve as important resources to enable marker-assisted selection (MAS) for nutritional improvement in mung bean and to analyze cultivars of mung bean

Molecular, Agronomical and Nutritional Characterization of Mung bean Germplasm

Mung bean (Vignaradiata L. 2n = 2x = 22), is an important legume food crop widely cultivated in East, South and Southeast Asia with an annual production world-wide of about 3.5-4.0 million tons. In this study, 408 and 94mung bean genotypes were characterized by agronomical along with nutritional traits and molecular marker, respectively. The aim of the study were (i) to characterize the mungbean germplasm with newly developed KASP based SNP marker and also with six agronomical and nine nutritional elements.(ii) to determine the genetic relationship among the genotypes based on these three parameters. 20 SNP markers were developed and among them 18 markers were polymorphic. The total alleles number was 38, with anwith an average of 1.9 alleles per locus. Polymorphism information content (PIC) value which was ranged from 0.00 to 0.3749, with an average of 0.2502. Two clusters were formed using UPGMA method where Cluster 2 was dominated by West and South Asia but Cluster 1 had genotypes of different origin. Population Structure analysis grouped 33 genotypes into two distinct population groups having 30% variation of the total variation, whereas 40 genotypes belong to admixture group. Under the agronomical characterization, positive correlation was existed between 50% flowering, initial maturity and 50% maturity. PCA analysis determined four agronomical traits among six traits which were mainly liable for generating variation. Four cluster formed using agronomical data in which Cluster 1 and Cluster 2 was predominant by Iran and India, respectively, whereas the remaining two clusters grouped genotypes of different origin. Nutritional analysis revealed that mung bean seeds are rich in K and P content. In addition, positive correlations were found between P and S, Ca with K, Mg and Fe, Fe with K and Mg, K and Mg. The outcome of this study will help to the breeder to make proper future plan for finding out the promising mungbean genotypes with high yielding ability along with biotic and abiotic resistan