Uncovering Superior Alleles and Genetic Loci for Yield-Related Traits in Mungbean (Vigna radiata L. Wilczek) Through Genome-Wide Association Study

Abstract

Mungbean is an important legume crop in South and Southeast Asia and Australia in terms of area coverage and production. However, productivity remains low due to limited genetic diversity, necessitating the dissection of the genetic basis of quantitatively inherited yield-related traits to develop stable and high-yielding varieties. In the current study, a total of 296 mungbean minicore germplasm accessions from the World Vegetable Centre were evaluated over three years in Bangladesh to assess their genetic diversity and local adaptation. Out of the 296 accessions, 206 produced flowers and yield, showing significant genetic variation in six yield-related traits: days to flowering (DF), days to maturity (DM), plant height (PH), pods per plant (PODS), 100-seed weight (HSW), and seed yield (YLD). Moderate to high broad-sense heritability was exhibited for all phenotypic traits, including DF (72%) and HSW (62%). Genome-wide association study (GWAS) was conducted using the 4,307 high-quality SNPs obtained from the genotyping by sequencing method and found 16 genetic loci across the six mungbean chromosomes associated with the six traits. Further, we selected 21 superior germplasm based on multi-trait stability index including four accessions with a higher number of favorable alleles (10). We also employed genomic prediction models and found a moderate prediction accuracy (>30%) for the HSW and YLD. These results will assist in incorporating important alleles into the elite mungbean germplasm through marker-assisted breeding and/or genomic prediction for improving mungbean yield.