Southern bacterial wilt, caused by the soilborne bacterium Ralstonia solanacearum (formerly Pseudomonas solanacearum), is a devastating disease of tomatoes. The bacterium enters the plant's roots through wounds and colonizes the xylem (or water-conducting tissues) of the plant. Disease develops rapidly during the hot days of mid- to late spring. Symptoms include the rapid loss of turgidity and wilting of the plant; the presence of brown, sunken cankers at the base of the plant; and brown internal discoloration of the vascular tissues and eventually the pith as well. Control of this disease is difficult at best as currently there are no resistant varieties available. Management of the disease relies on avoiding areas with a history of the disease. If this is not possible, avoid planting susceptible crops in the area for at least 3-4 years. For more information, please see the fact sheet in the Louisiana Plant Pathology Disease Identification and Management series.