General Information: Agrobacterium vitis is the causative agent of crown gall disease in grapes. Agrobacterium are Gram-negative, motile, soil-dwelling plant pathogens with the species name given based on the disease phenotype associated with the bacteria. Disease causing Agrobacterium spp. possess a tumor-inducing (Ti) plasmid, which carries genes for the formation of opines. A segment of the Ti plasmid gets transferred to the plant cell and integrates into the host cell genome. The plant cell then starts synthesizing opines, which can be catabolized by Agrobacterium spp, but not by the plant cells.