Genetic Modification of Grapevine Embryogenic Cultures

Precision breeding is an approach to grapevine genetic improvement that transfers only specific traits among sexually compatible species via the relatively stable mitotic cell division pathway in order to avoid the significant disruption imposed upon conventional breeding by meiosis. Factors enabling precision breeding include the availability of the Vitis genome sequence combined with highly optimized gene insertion and plant regeneration protocols. A protocol for the production of grapevine embryogenic cultures and their genetic transformation is described. Embryogenic cultures are produced from either leaf or floral explants. Somatic embryos at the cotyledonary stage of development are used for Agrobacterium-mediated transformation. Following co-cultivation with Agrobacterium containing the genes of interest, modified embryos are selected on the basis of anthocyanin pigmentation and antibiotic resistance. Somatic embryos are then germinated to produce modified plants that are hardened and transferred to a greenhouse. The presence of the genes of interest is confirmed by PCR.