Conference Proceeding

Identification of Genomic Loci Contributing to Various Yield Traits in Common Bean

Ms. Nancy Gupta

Common bean (Phaseolus vulgaris L.) is considered to be the world’s most important grain legume, used directly for human consumption in all parts of the world. It contains substantial amount of proteins, carbohydrates, minerals, vitamins, flavonoids and other phenolic compounds which makes it highly nutritious and applicable for medicinal purposes. The present work aimed to study the marker-trait association for yield traits in 96 diverse common bean accessions collected from Himalayan regions of J&K. We performed association analyses of nine phenotypic traits using 99 microsatellite markers (genomic and genic SSRs) for identification of molecular markers linked to yield performance of the crop. The morphological data was recorded and pooled for the two consecutive years was found significant at 0.01% level of significance for all the parameters with highest variance observed for seeds per plant trait. Heritability ranged from 85% to 99.9% suggesting the usefulness of morphological parameters under consideration for direct selection. Further, high level of genetic variation was detected by molecular evaluation with polymorphic information content ranging from 0.2143 to 0.8328 and gene diversity from 0.2278 to 0.8508. Both the parameters showed minimum value for Bmb1008 marker and maximum for BM150 marker. For the assessment of genetic relationship, the genotypes were divided into two separate groups (K=2) by population structure analysis using STRUCTURE software. Most of the genotypes belonging to the same region fall in the same cluster. Few of them were found to have mixed ancestry. Finally, correlation between genotype and phenotype was estimated through linkage disequilibrium (LD) approach by association analysis performed using TASSEL software. A total of 16 marker-trait associations were found significant (p≤ 0.005). Association for more than one trait was observed in three markers, Bmd8 (for days to bud initiation for 17.9% and days to fruiting 17.6%), BM153 (for pod length for 21.8% and days to bud initiation for 21.4%) and X96999 (pods per plant for 31.6% and seeds per plant for 28.2%). For 100 seed weight, PVBR87, BM141 and BM114 were found significant at 32.7%, 18.4% and 17.3% respectively. Association for yield traits such as days to bud initiation (PVBR 213 for 30.3%), days to fruiting (Bmd803 for 21.3%), pods per plant (X96999 for 31.5%), pod length (X57022 and BM170 for 31.6% and 20.1% res.), pod width (M75856 and Bmd37 for 20.25% and 14.4% res), seed yield per plant (Bmc234 for 16.7%) was obtained. Previous reports suggest linkage of BM141, Bmd8 and X96999 for yield, BM170 for pod length and Bmd37 for 100 seed weight which further validate our results. These markers can further assist plant breeders to carry out marker assisted selection to enhance yield in common bean.

Published: 08 November 2017


Copyright: © 2017 Ms. Nancy Gupta. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.