Optimization of the uidA gene transfer into somatic embryos of rose via Agrobacterium tumefaciens

The effects of different concentrations of kanamycin (10-250 mg l–1), carbencillin (250 and 500 mg l–1), cefotaxime (250 and 500 mg l–1), and combinations of carbencillin and cefotaxime (each at 150 mg l–1) on regeneration from different tissues of rose (Rosa hybrida cv. Carefree Beauty), including leaf, undifferentiated callus, and primary embryogenic callus, were investigated. The pCAMBIA 2301 plasmid, containing the uidA gene coding for β-glucuronidase (GUS) gene expression driven by the CaMV 35S promotor and the npt II gene for kanamycin resistance, was immobilized into Agrobacerium tumefaciens strain GV3101, and used for transformation of leaf, undifferentiated callus, and primary embryogenic callus. Although all sources of explants showed GUS activity following transformation, transgenic plants were only induced from transformed primary embryogenic callus. Stable integration of the transgene was confirmed by both PCR and Southern hybridization.