Determination and partial molecular characterization of Plum pox virus in Bolu province

Plum pox virus (PPV), the causal agent of Sharka disease, causes yield, quality, and economic losses in stone fruits. PPV has been reported worldwide, especially in Europe. In studies to date, the presence of the virus has been identified as being restricted in different regions of Turkey. However, there is no record of PPV in Bolu province so far. Hence, surveys were carried out in Bolu province between 2016-2019, and a total of 306 samples were collected. To determine the presence of PPV, the samples were first tested by DAS-ELISA, and only three peach samples were found to be infected. DAS-ELISA results of infected samples were confirmed by RT-PCR using universal primers (P1/P2), then infected samples were identified at the strain level using strain-specific primers. The samples were found to be infected with the PPV-M (Marcus) strain and 243-bp long nucleotide sequences containing the partial coat protein gene of three isolates were deposited to NCBI. Phylogenetic analysis (Neighbor-Joining) generated by 38 representative PPV sequences indicated that Bolu isolates were clustered with PPV-M isolates and separated from other strains, as in BLAST analysis. To our knowledge, this is the first report of PPV in Bolu. This study reveals the necessity to carry out more extensive surveys to prevent the PPV dissemination in Bolu and to identify the complete genomes of the obtained isolates to determine their genetic variation. All the PPV-infected trees were destroyed as a consequence.