Screening of snap and dry bean (Phaseolus vulgaris L.) genotypes for resistance to Bean common mosaic virus and Bean common mosaic necrosis virus

The most effective control of Bean common mosaic virus (BCMV) and Bean common mosaic necrosis virus (BCMNV) is achieved by using the seeds of resistant cultivars. During conventional breeding, resistance against BCMV and BCMNV in common bean can be developed by pyramiding the strain-nonspecific dominant I gene with strain-specific recessive (bc-) resistance genes for long-term virus control. In this study, a total of 58 bean genotypes involving registered green and dry bean cultivars, local genotypes, and breeding lines were tested for the presence of known resistance genes. First of all, each genotype was inoculated with the NL-3 strain of BCMNV and the NL-4 strain of BCMV separately, and the plants were evaluated for the symptom appearance and tested by DAS-ELISA to confirm the presence or absence of the virus after three weeks of sap-inoculation. In the last part of the study, the resistance genes in bean genotypes were investigated by SCAR markers of SW-13 linked with the I gene and SBD-5 linked to bc-12. According to the phenotypic and molecular tests, out of 58 common bean genotypes tested, 37 involved the I gene, and seven and three genotypes contained bc-22 and bc-12 genes, respectively.