Higher Effectiveness of New Common Bean (Phaseolus vulgaris L.) Germplasm Acquisition by Collecting Expeditions Associated with Molecular Analyses

A remarkable portion of crop genetic diversity is represented by landraces and obsolete cultivars, that have not yet been integrated into the collections of genetic resources in genebanks. Fortunately, they are still maintained by small farmers in rural areas. Their acquisition is an important goal for collecting expeditions, followed by the evaluation of their genetic background. Molecular markers are powerful tools to evaluate the effectiveness of acquisition of new genetic variants. This approach was used for common bean landraces, that were collected through expeditions in the Slovak and Ukrainian Carpathians. In this study, microsatellite markers, developed from expressed sequence tags, were used for genotyping the collected materials. The sub-population of collected landraces contained higher total and average number of different alleles in comparison to equally large sub-populations of already-maintained cultivars. The same was true for the Shannon's information index, observed heterozygosity, and expected heterozygosity. Both sub-populations showed the presence of private alleles: Average values of 0.500 and 0.833 private alleles per genotype were detected in landraces, and cultivars, respectively. Obtained results emphasized the importance of collecting expeditions to specific regions where landraces are cultivated, even at the present time. The effectiveness of the acquisition of new genetic variability can be determined by molecular tools, as confirmed by microsatellite markers in this study.