Agrobacterium-mediated transformation and plant regeneration of Brassica oleracea var. capitata

An efficient protocol for Agrobacterium tumefaciens-mediated transformation of four commercial cultivars of Brassica oleracea var, capitata is describ ed. A strain of A. tumefaciens LBA4404 with the neomycin phosphotransferase gene (nptII) and a CaMV 35S-peroxidase gene cassette were used for coculti vation. Preliminary selection of regenerated transgenic plants was performe d on kanamycin-containing medium. The frequency of transgenic plants was ca lculated on the basis of GUS (beta-grucuronidase) activity detected by the histochemical X-gluc test. Tissue-specific GUS expression driven by the per oxidase gene promoter in transgenic plants was analysed by GUS staining. Th e transformation rates of the commercial cultivars of B. oleracea was highe r than in previous reports. Southern blot analysis revealed that integratio n of marker genes occur;rd in single and multiple loci in the genome. All t ransgenic plants grew normally after a brief vernalization period and showe d stable inheritance of the marker gene. The present study demonstrates tha t morphologically normal, fertile transgenic plants of B. oleracea can be o btained.