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

Abstract

Mungbean (Vigna radiata L.) quality is dependent on seed chemical composition, which in turn determines the benefits of mungbean consumption for human health. While rich in a range of nutritional components, such as protein, mineral nutrients, carbohydrates and several vitamins, mungbean remains behind many other crops in the availability of genomic and genetic resources. To further improve mineral nutrient levels in mungbean seeds requires the development of genome-wide tools. The objectives of this research were to develop these tools and conducted nutrient analysis in order to 1) identify genome-wide single nucleotide polymorphisms (SNPs) using genotyping by sequencing (GBS) and 2) perform genome-wide association studies (GWAS) for levels of calcium, iron, potassium, manganese, phosphorous, sulfur, and zinc in the seed in two years. A total of 112 GWAS models were explored using 6,486 high quality SNPs discovered in 92 mungbean accessions. The data obtained allowed for the identification of 43 associated SNPs and 20 main genomic regions that explained on average 22 % of the overall variation in seed mineral contents on the basis of a multiple-year analysis. Most of the discovered regions in this study provide valuable information for mungbean breeding of new varieties with novel nutritional properties and offer a starting point to identify the underlying genes, which will help to reveal the genetic basis of mungbean seed nutritional properties. The SNPs identified in this study will serve as important resources to enable marker-assisted selection (MAS) for nutritional quality traits in legume breeding programs.

Key words: Biofortification, Single nucleotide polymorphism (SNP), GWAS, mineral nutrients