Regeneration of transgenic plants of grapevine (<i>Vitis vinifera</i>L.) via<i>Agrobacterium</i>rhizogenesmediated transformation of embryogenic calli

Abstract

Genetically transformed roots and calli were induced from leaf segments of grapevine (Vitis vinifera L. cv. Koshusanjaku) after co-cultivation with wild-type Agrobacterium rhizogenes strains, but plant regenera tion from them was not achieved. On the other hand, transgenlc grapevine plants were obtained via somatic embryogenesis after co-cultivation of embryogenic calli with an engineered A. rhizogenes strain including both the neomycin phosphotransferase II (NPT II) and the β-glucuronidase (GUS) genes, followed by selection of secondary embryos for kanamycin resistance. All these plants showed GUS gene expression revealed by histochemical assay. Southern blot analysis revealed the stable integration of the GUS cording region in their genome. Transformants containing Ri T-DNA exhibited various phenotypes: most of them showed a typical Ri-transformed phenotype such as wrinkled leaves, while the others looked normal.