Serological evidence for the occurrence of races in Sclerospora graminicola and identification of a race-specific surface protein involved in host recognition

Abstract

A protein specific to a virulent pathotype of the downy mildew pathogen Sclerospora graminicola was identified on the Western transfers using the cross-adsorbed antibody. This protein was approximately 90 kDa and without subunits. Serological agglutination studies localized the protein on the cell wall surfaces. Enzyme linked immunosorbent assay and dot blotting using the specific antibodies identified distinct races of the pathogen. Immunofluorescence studies and enzyme linked immunosorbent assay using suspension cultures of host cells showed that the protein bound to the cells of susceptible cultivar but not to those of resistant cultivar. These results suggested that this protein may be involved in host recognition.