Agrobacterium-mediated transformation of white mustard (Sinapis alba L.) and regeneration of transgenic plants

A procedure for the regeneration of fertile transgenic white mustard (Sinapis alba L.) is presented. The protocol is based on infection of stem explants of 7-9 day old plants with an Agrobacterium tumefaciens strain harboring a disarmed binary vector with chimeric genes encoding neomycin phosphotransferase and β-glucuronidase. Shoots are regenerated from callus-forming explants within 3-4 weeks. Under selection, 10% of the explants with transgenic embryonic callus develop into fertile transgenic plants. Rooting shoots transferred to soil yield seeds within 14-16 weeks following transformation. Integration and expression of the T-DNA encoded marker genes was confirmed by histochemical β glucuronidase assays and Southern-DNA hybridization using primary transformants and S1-progeny. The analysis showed stable integration and Mendelian inheritance of trans-genes in transformed Sinapis lines.