Allorhizobium vitis

Allorhizobium vitis is a plant pathogen that infects grapevines. The species is best known for causing a tumor known as crown gall disease. One of the virulent strains, A. vitis S4, is responsible both for crown gall on grapevines and for inducing a hypersensitive response in other plant species. Grapevines that have been affected by crown gall disease produce fewer grapes than unaffected plants. Though not all strains of A. vitis are tumorigenic, most strains can damage plant hosts.

A. vitis shares many genetic and morphological characteristics with several Agrobacterium species, including A. tumefaciens. The two species have overlapping host ranges, and both A. vitis and A. tumefaciens may reduce the yield of infected crops. For this reason, research on A. vitis focuses on transmission and methods of control.