Purification, Serology and Nucleic Acid of Oat Sterile Dwarf Virus Subviral Particles

Abstract

SUMMARY Oat sterile dwarf virus (OSDV) subviral particles (SVPs) were purified from roots and stem bases of Lolium multiflorum. Electron microscopy of the preparations showed B-spiked SVPs typical of Fijiviruses (Fiji disease and maize rough dwarf-like viruses). Two sera with titres in gel-diffusion tests of 1/512 and 1/2048 were prepared against the SVPs. The sera did not react with the SVPs of maize rough dwarf and pangola stunt viruses when tested by gel-diffusion and immuno-electron microscopy. The first serum did not react with virus dsRNA or poly (1).poly(C) and the second serum had a titre of 1/8 with each of these. Poly-acrylamide gel electrophoresis of the nucleic acid from purified OSDV SVPs revealed ten dsRNA segments though only nine of these were resolved as separate bands in dsRNA extracted directly from infected plants. The genome pattern was broadly similar to but distinct from those of the known Fijiviruses. The RNA of the serologically related Arrhenatherum blue dwarf virus (ABDV), extracted directly from plants, appeared identical to that extracted directly from OSDV-infected plants. Both OSDV and ABDV were transmitted by the planthopper vector Javesella pellucida despite, in the case of OSDV, having been maintained in vegetatively propagated plants for 5 years.