gall An abnormal growth that occurs in plants. It may be caused by insects, mites, nematodes, fungi, or bacteria. By definition, galls are self-limiting growths required the continued presence of the inciting organism for full development. They thereby differ from tumors, where abnormal growth continues in the absence of the inciting organism. However, in crown gall disease of crucifers (e.g., cabbage), the bacterium Agrobacterium tumefaciens is required for the initiation of the gall, but subsequent growth becomes tumorous and does not require the presence of the bacterium. Related category • BOTANY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |