The Ralstonia solanacearum species complex includes R. solanacearum itself, R. syzygii, and the Blood Disease Bacterium (BDB). All three colonize plant xylem vessels and cause wilt diseases, but with significant biological differences. R. solanacearum is a soilborne bacterium that infects the roots of a broad range of plants to cause bacterial wilt disease. R. syzygii causes Sumatra disease of clove trees and is actively transmitted by cercopoid insects. BDB is also pathogenic to a single host, banana, and is transmitted by pollinating insects.