Association Mapping for Yield Attributing Traits and Yellow Mosaic Disease Resistance in Mung Bean [Vigna radiata (L.) Wilczek]

Abstract

Mung bean [Vigna radiata (L.) Wilczek] is an important short-duration grain legume widely known for its nutritional, soil ameliorative, and cropping system intensification properties. This study aims at evaluating genetic diversity among mung bean genotypes and detecting genomic regions associated with various yield attributing traits and yellow mosaic disease (YMD) resistance by association mapping. A panel of 80 cultivars and advanced breeding lines was evaluated for 10 yield-related and YMD resistance traits during kharif (monsoon) and summer seasons of 2018–2019 and 2019–2020. A total of 164 genome-wide simple sequence repeat (SSR) markers were initially screened, out of which 89 were found polymorphic which generated 317 polymorphic alleles with an average of 3.56 alleles per SSR locus. The number of alleles at each locus varied from 2 to 7. The population genetic structure analysis grouped different genotypes in three major clusters and three genetically distinct subpopulations (SPs) (i.e., SP-1, SP-2, and SP-3) with one admixture subpopulation (SP-4). Both cluster and population genetic structure analysis categorized the advanced mung bean genotypes in a single group/SP and the released varieties in other groups/SPs, suggesting that the studied genotypes may have common ancestral history at some level. The population genetic structure was also in agreement with the genetic diversity analysis. The estimate of the average degree of linkage disequilibrium (LD) present at the genome level in 80 mung bean genotypes unveiled significant LD blocks. Over the four seasons, 10 marker-trait associations were observed significant for YMD and four seed yield (SY)-related traits viz., days to flowering, days to maturity, plant height, and number of pods per plant using the mixed linear model (MLM) method. These associations may be useful for marker-assisted mung bean yield improvement programs and YMD resistance.

Association mapping for important agronomic traits in wild and cultivated Vigna species using cross-species and cross-genera simple sequence repeat markers

“…Successful transferability of SSRs from adzuki bean, common bean, and scarlet runner bean was Frontiers in Genetics frontiersin.org reported earlier in mungbean (Wang et al, 2009;Dikshit et al, 2012;Gupta et al, 2013a;Pratap et al, 2015;Pratap et al, 2016;Pratap et al, 2020;Kumari et al, 2021). Earlier, cross-genera-and cross-species-specific SSRs have been very well utilized in linkage and association mapping for identifying genes/QTLs responsible for various traits in mungbean, blackgram, V. marina, and cowpea in addition to their use in studying genetic diversity (Isemura et al, 2012;Gupta et al, 2013b;Singh et al, 2020;Rohilla et al, 2021;Vadivel et al, 2021). Agronomically important yield-attributing traits, namely, PH, NSP, HSW, DF, DM, and resistance to various biotic and abiotic stresses, in most of the crop plants are likely to be controlled by many genes/QTLs with additive gene actions (Bharadwaj et al, 2021).…”

“…Successful transferability of SSRs from adzuki bean, common bean, and scarlet runner bean was reported earlier in mungbean ( Wang et al, 2009 ; Dikshit et al, 2012 ; Gupta et al, 2013a ; Pratap et al, 2015 ; Pratap et al, 2016 ; Pratap et al, 2020 ; Kumari et al, 2021 ). Earlier, cross-genera- and cross-species-specific SSRs have been very well utilized in linkage and association mapping for identifying genes/QTLs responsible for various traits in mungbean, blackgram, V. marina , and cowpea in addition to their use in studying genetic diversity ( Isemura et al, 2012 ; Gupta et al, 2013b ; Singh et al, 2020 ; Rohilla et al, 2021 ; Vadivel et al, 2021 ).…”

“…In this direction, the genome-wide association study (GWAS) is a high-resolution method for genetic mapping of traits using existing germplasm and their phenotypic information for the trait concerned ( Flint-Garcia et al, 2003 ). It also helps us understand the genetic basis of complex traits and allows studying a wide range of alleles at each locus and the identification of useful marker–trait associations at the whole-genome level in addition to the identification of elite alleles for significantly associated loci ( Rohilla et al, 2021 ). The higher mapping resolution of traits from association mapping provides an opportunity for the adoption of MAS in crop breeding programs ( Mackay and Powell, 2007 ).…”

Genome wide association analysis for grain micronutrients and anti-nutritional traits in mungbean [Vigna radiata (L.) R. Wilczek] using SNP markers

“…Noble et al ( 71 ) and Breria et al ( 72 ) previously reported the occurrence of four subpopulations among the 466 different mungbean accessions and 297 mungbean minicore collections, respectively. Versha et al ( 73 ) recently discovered four subpopulations in an association mapping analysis comprising 80 genotypes. The genomic resources developed in this study will pave the way for the discovery of SNPs/candidate genes linked to agronomic traits in mungbean.…”

Assessment of Simple Sequence Repeat (SSR) Markers Derived from Whole-Genome Sequence (WGS) of Mungbean (Vigna radiata L. Wilczek): Cross-Species Transferability and Population Genetic Studies in Vigna Species

“…It is an autogamous crop with 2n = 2x = 22 chromosomes that span about 574 Mega base pairs of genetic material [4]. The small genome size makes it a suitable model crop for studying evolutionary and genetic diversity [5].…”