Serological studies on bromegrass mosaic virus and its protein fragments

The serological properties of the capsids and dissociated protein subunits of bromegrass mosaic virus have been compared by immunodiffusion tests. Methods were developed to obtain non-mutually contaminated protein and virus preparations as well as the corresponding antisera. The breakdown of the capsids and the reaggregation of the subunits inside the agar gel during immunodiffusion tests was prevented by controlling the ionic environment inside the gel and by treating the antigens with formalin. The existence of antigenic determinants specific for only the capsid surface as well as that of determinants specific for only the dissociated subunit surface was demonstrated by intragel cross-absorption tests.