Abstract
Corynebacterium insidiosum and Corynebacterium sepedonicum, the causative agents of bacterial wilt of alfalfa and of potato ring rot, produce viscous polysaccharide solutions when grown in shaken culture. These substances contain fucose, a sugar rarely found in polysaccharides of land plants. Hydrolyzates of polysaccharides extracted from alfalfa and potato plants infected with these organisms also contained fucose, while extracts of healthy plants did not. Alfalfa cuttings placed in dilute polysaccharide solutions wilted rapidly. These findings suggest that these polysaccharides are probably formed in the vascular systems of infected plants and that if such is the case they contribute to the development of the disease in these plants.