Patent ID: 8334429

Claim:
A method of transforming and regenerating a plant cell expressing a transgene, without an Agrobacterium counter-selective agent, comprising: contacting a plant cell with an Agrobacterium that is a thymidine auxotroph, in the presence of thymidine or thymine necessary for the auxotrophic Agrobacterium's survival, proliferation or growth, wherein said auxotroph comprises a transgene; co-cultivating the plant cell with the thymidine auxotroph in the presence of thymidine or thymine; selecting in the absence of an Agrobacterium counter-selective agent for the transformed cell expressing the transgene, and in the absence of thymidine or thymine; and regenerating from the selected transformed plant cell a plant expressing the transgene, in the absence of an Agrobacterium counter-selective agent and in the absence of thymidine or thymine; wherein the thymidine auxotrophic Agrobacterium comprises a disrupted thyA gene which encoded thymidylate synthase prior to disruption.