Revisiting population genetics with new genomic resources in dolichos bean (Lablab purpureus L. Sweet): an orphan crop

Strategies to improve a crop depend on a better understanding of its genetic architecture. In the era of genomics, it is important to develop new efficient genomic resources for orphan crops, considering the growing demand for the crop. Dolichos bean, a high-potential, nutrient-rich orphan legume crop, is gaining importance in many parts of the world. Hence, accelerating breeding activity with marker-assisted approaches is much needed. We developed a total of 670 simple sequence repeat (SSR) markers from the genome sequence information as new genomic resources for the crop. In order to assess the effectiveness of markers to use in genetic research, ensuring the informativeness of new genomic resources is a prerequisite. Hence, new markers were assayed on 96 diverse accessions and examined for their potential to explain population genomics. These new markers consisted of both di- and tri-nucleotide repeats in equal proportions. The population genetic parameters estimated with this marker information proved their efficiency in delineating genetic variations in the population. Results reinforced the relationships between the effective number of alleles, gene diversity, and polymorphic information content, thereby suggesting the informativeness of new markers as genomic resources. Population structure and gene flow information generated will be useful to understand the population dynamics of the dolichos bean. The classification of genotypes into clusters using marker information and the comparison of cluster phenotypes indicated the effectiveness of marker alleles in assessing genome diversity. At the outset, the results of the present study strongly prove the effectiveness of new genomic SSR markers to utilize in genomics-assisted breeding in dolichos bean.