Callus Induction and Plant Regeneration of Rosa wichuraiana ‘Basye’s thornless’

Methods of callus induction and plant regeneration of Rosa wichuraiana ‘Basye's thornless’ were investigated using in vitro grown young leaflets as explants. Results showed that calli were induced on MS with a high concentration of auxin (NAA), with calli exhibiting direct differentiation of adventitious buds after induction on MS medium with TDZ under dark and then light conditions. The optimal concentration of auxin (NAA) for calli induction of R. wichuraiana was 7.0 mg/L, the optimal induction period in the dark for adventitious bud differentiation was 10 d and the optimal differentiation medium was MS + 5.0 mg/L TDZ + 30 g/L glucose + 2.5 g/L GEL (pH 5.8-6.0). The highest rate of adventitious bud induction was 18.34%. We used the calli obtained by induction as transformation receptors to research GUS gene conversion. We also conducted a preliminary study on the Agrobacterium tumefaciens-mediated transformation protocol for R. wichuraiana. Results showed that the optimal conditions for transformation of R. wichuraiana was a bacterial concentration (OD₆₀₀) of 0.5, infection time of 30 min, co-cultivation time of 2 d, and acetosyringone concentration of 50 μmol/L.