GENETIC ENGINEERING OF GRAPE FOR RESISTANCE TO CROWN GALL

Embryo cultures of rootstock Richter 110 were generated and subsequently transformed via the Agrobacterium process with truncated virE2 genes that were isolated from A. tumefaciens strains C58 and A6 and from A. vitis strain, CG450. The resulting genes encode VirE2 proteins lacking 215 amino acids from their carboxy terminus; a region predicted to be associated with DNA binding.
Regenerated transgenic grape plants were selected on kanamycin media and were characterized by PCR and by Southern analysis.
Regenerated plants were first screened for susceptibility to crown gall by inoculating shoot explants in vitro with strains of A. tumefaciens strains C58 and A6. Galls consistently developed on approximately 90% of the inoculated, non-transformed explants.
Seven lines transformed with the C58 gene expressed resistance to C58. None of the lines transformed with the other virE2 constructs were resistant.
The seven resistant lines were screened for resistance to C58 and A. vitis strains TM4 (octopine type Ti plasmid) and CG450 (vitopine type Ti plasmid) on mature shoots of plants growing in the greenhouse.
Two of the lines were resistant to infection by all three of the Agrobacterium strains and other lines demonstrated resistance to specific strains.

VIII International Conference on Grape Genetics and Breeding

M. Holden, S. Krasatanova, B. Xue, S. Pang, M. Sekiya, E.A. Momol, D. Gonsalves

Agrobacterium vitis, embryo culture

https://doi.org/10.17660/ActaHortic.2003.603.62