Diversity of Plum Pox Virus isolates in Bosnia and Herzegovina

Sixteen Plum pox virus (PPV) isolates from several stone fruit cultivars, host species, orchards and geographical areas ofBosnia and Herzegovina were selected for typing, using serotype-specific monoclonal antibodies (MAbs) and PCR–RFLP,targeting the 3′ terminal region of the coat protein (CP) and P3-6K1 with restriction enzymes RsaI and DdeI. Four PPVisolates were identified as PPV-M by serology and PCR; eight isolates were identified as PPV-D based on PCR–RFLP onboth genomic regions, but were not recognized by the D-specific MAb4DG5. Four isolates from plum were identified asnatural D/M recombinants (PPV-Rec), based on conflicting results of CP and P3-6K1 typing. To investigate the geneticdiversity of Bosnian PPV isolates in more detail, five isolates (three PPV-Rec, one PPV-M and one PPV-D) were partiallysequenced in the region spanning the 3′ terminal part of the NIb gene and the 5′-terminal part of the CP gene, corre-sponding to nucleotides 8056–8884. Nucleotide sequence alignment of recombinant isolates showed that they wereclosely related at the molecular level to previously characterized recombinants from other European countries, andshared the same recombination break point in the 3′ terminal part of the NIb gene. This is the first report of naturallyinfected Prunus trees with PPV-M, PPV-D and PPV-Rec in Bosnia and Herzegovina. The high variability of the BosnianPPV isolates fits with the presence of this virus in the country over a long period