Genetics of white rust resistance in Indian mustard (Brassica juncea L.) and its validation on using molecular markers

White rust resistance loci (AcB1-A4.1 and AcB1-A5.1) associated with intron polymorphic (IP) markers i.e. At5g41560 and At2g36360, respectively, were used for validation of P1, P2, F1, F2, BC1F1 and BC2F1 generations. The donor parents namely, Bio-YSR and BEC-144 produced desired banding pattern of 430 and 750 bp while recipients viz., NRCHB 101 and DRMR-150-35 exhibited different pattern from donors confirming white rust resistance loci 4.1 and 5.1 with marker At5g41560 and At2g36360, respectively. Confirmation of these set of two IP markers in the parents and F1s lead us to further screening of selected F2, BC1F1 and BC2F1 populations. Available data on white rust reaction in different generations under study revealed that single dominant gene is responsible for white rust resistance. Potential of molecular markers in developing white rust resistant genotypes is proved under present study.