Screening of important bean genotypes/collections for resistance against Common Bean Mosaic Virus using molecular markers

Bean Common Mosaic Virus (BCMV) causes one of the most serious diseases affecting common bean production. This potyvirus is spread non-persistently by aphids and is also seed-borne. In present investigation out of 132 genotypes selected for screening for BCMV only 8 genotypes (WB-399, WB-640, WB-359 & WB-375, WB-494, WB-933 & WB-939, WB-335) were found phenotypically resistant against it, which was later ascertained by molecular analysis by different microsatellite markers. The variable number of bands produced by different primers ranged from 5 to 22 with an average of 11.4 bands per primer and with level of polymorphism 24.5%. Among the molecular markers used, SSR marker named 835 produced a maximum of 6 alleles, followed by marker 841 then by marker 827 then by BMD-1 followed by ROC-11then followed by marker EIF-4E then followed by SBD-5 and finally by SW-13 that produced 3 alleles each. The polymorphism information content (PIC) was calculated for all the markers, and was highest for Primer BMD-6 which exhibited PIC value of 0.49 and the lowest for the primer BMD-2 (0.22). Hence, primer BMD-6 was observed to be highly informative and serve as an effective and useful marker to determine the genetic differences among the common bean accessions and also to study the phylogenetic relationships.