The Association of Brome Mosaic Virus and Wheat Rusts.

Evidence is presented in support of transmission of brome mosaic virus by uredospores of wheat stem rust (Puccinia graminis f. sp. tritici). The presence of BMV associated with uredospores is shown by the use of sensitive serological assays such as, fluorescent antibody binding studies, enzyme-linked immunosorbent assay and immunosorbent electron microscopy. The virus is shown to be carried externally on the uredospores. The nature of the association of the virus with uredospores and its relation to the mode of carriage and transmission of the virus by the uredospores, as well as the importance of this association in the epidemiology of the virus is discussed.