Discovery and molecular characterization of a novel Plum pox virus strain

Abstract

Aim. Atypical isolates of Plum pox virus (PPV) discovered in naturally infected sour cherry in urban ornamental plantings in Moscow, Russia have been studied. Methods. The isolates were detected by polyclonal double antibody sandwich ELISA and RT-PCR using universal primers specific to 3’-non-coding and to coat protein (СP) genome regions but failed to be recognized by triple antibody sandwich ELISA with the universal monoclonal antibody 5B and by RT-PCR using primers specific to the conventional PPV strains. Results. The CP gene sequence analysis of 9 isolates revealed the 99.2 – 100% of within-group identity and 62 - 85% identity with the conventional PPV strains. Conclusion. Phylogenetic analysis and alignment of the N-terminal CP aa sequences showed that the atypical isolates represent a group distinct from the known PPV strains and belong to a new tentative PPV strain CR.

Key words: Plum pox virus, sour cherry, phylogenetic analysis, PPV strain CR.