Comparison of Potato Yellow Dwarf Virus Serotypes

Abstract

Three isolates of potato yellow dwarf virus (PYDV) were compared. The California (SYDV-CA) and New York (SYDV-NY) isolates of PYDV were representative of the SYDV serotype, while the New Jersey isolate (CYDV-NJ) represented the CYDV serotype. Serotype differences were readily observable by immunodiffusion and double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) tests, but were less apparent by indirect ELISA. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of virion proteins showed distinct MW differences for at least 2 virion proteins between the 2 PYDV serotypes. Proteins G and M2 of CYDV-NJ had MW of 92,500 and 29,000, respectively, compared to 85,000 and 24,000 for the corresponding proteins of the SYDV-CA and SYDV-NY serotypes. Despite their physical differences, the G proteins of the 2 serotypes cross reacted in indirect ELISA. Virion protein MW, as well as serological properties, can be used to separate PYDV serotypes.