Development of common bean (Phaseolus vulgaris L.) lines resistant to bean common mosaic virus (BCMV) and anthracnose (Colletotrichum lindemuthianum) diseases via marker assisted backcrossing method

In this study, the development of lines tolerant to anthracnose and BCMV was aimed using the marker-assisted backcrossing (MASBC) method. As materials, two promising lines, two commercial cultivars, and one genotype carrying resistance genes were used. CAPS, RAPD, and SCAR markers were utilized in MASBC studies to detect resistance genes. As a result of backcrossing bean lines/cultivars with BMN RMR-13, 92 F2, 52 BC1, 51 BC2, 44 BC3, and 72 BC3F1 lines carrying the resistance gene combinations bc-3+Co-1+I, bc-3+Co-42+I, and bc-3+Co-6+I were obtained. The obtained lines were included in the field trial in the 2024 growing season and the experiment was carried out with 3 replicates according to the coincidence blocks experimental design.. In the trial, the genotypes exhibited the following ranges: emergence time 13.83–18.00 days, flowering time 42.00–71.66 days, pod-setting time 52–83 days, maturation period 81.0–112.2 days, hypocotyl thickness 2.94–4.28 cm, hypocotyl length 3.30–9.78 cm, plant height 44.26–129.00 cm, number of branches per plant 3.26–4.73, first pod height 9.73–27.2 cm, number of pods per plant 9.73–47.13, seed yield per plant 12.66–60.06 g/plant, thousand seed weight 359.8–616.6 g, biological yield 71.66–151.53 g/plant, harvest index 13.07%–40.71%, number of seeds per pod 2.02–3.49, seed length 12.62–17.83 mm, seed width 5.56–6.56 mm and seed diameter 6.73–8.14 mm. As a result of the study, the obtained lines were decided to undergo pathogenicity tests and be transferred to regional yield trials.