Tobacco streak virus (TSV) or red node is vectored by two species of thrips. In addition to dry bean, other known hosts of the virus include white sweet clover, yellow sweet clover, asparagus and cowpea. The disease is of rare occurrence on the Central High Plains and seldom causes economic loss.
Red node infection causes a reddish discoloration of nodes at the point of attachment of leaf petioles to stems. In severe cases, infected plants will flex or break at a discolored node. Veins and veinlets of leaves exhibit a red to reddish-brown streaking. Red to reddish-brown concentric rings form on pods which become shriveled or puffy and do not produce seeds. Plants can be severely stunted and killed by the virus.
No biological control strategies have been developed for red node.
Red node occurs so infrequently that cultural control strategies have not been developed. The planting of certified seed is advisable since the virus can be seed-borne. Some breeding lines appear more susceptible than others, but the reaction of most commercial varieties is unknown.
Chemical controls have not been developed for red node. Thrips control is probably ineffective.
Categories: Dry Bean, Disease, Red Node, Tobacco Streak
Date: 04/01/2007