The use of phosphinothricin resistance as selectable marker for genetic transformation of grapevine

A transformation procedure with the bar gene as a selectable marker was established via Agrobacterium-mediated transformation using strain LBA4404 harbouring the vector pPZP200-bar-gus-intron. Recreation of embryogenic cells from transformation stress in PPT free medium for four weeks improved viability and number of GUS expressing cells. Concentration of 2.5 mg·l-1 PPT yielded highest selection efficiency. Transgenicity of the regenerated grapevine plants was confirmed by histochemical GUS assay and bar specific PCR and RT/PCR. With the described procedure, 20 % of regenerated embryos could be converted into transgenic grapevines.