Résumé
Plum pox virus (PPV, genus Potyvirus) is responsible for sharka, the most important Prunus disease in many countries throughout the world. Although reported in almost all Eastern and Central European countries, PPV presence and diversity in the Republic of North Macedonia are still not officially documented. For this reason, a country-wide survey was carried out in June 2018 targeting cultivated, sub-spontaneous and wild Prunus trees including P. persica, P. armeniaca, P. domestica and P. cerasifera. Leaf samples were collected on 173 trees exhibiting no, typical or atypical sharka symptoms. PPV was detected in 119 (69%) samples by ELISA and/or IC-RT-PCR using polyvalent PPV primers. Strain typing was then performed by PCR using PPV-D, PPV-M and PPV-Rec specific primers. Isolates typed as PPV-M were the most frequently detected (74%), followed by the ones typed as PPV-Rec (18%) and PPV-D (8%). A single mixed infection (M+D) was found. The 3 strains had unequal geographical and host species distributions. All isolates typed as PPV-Rec except one were restricted to eastern Macedonia, mostly in P. domestica and P. cerasifera trees, whereas isolates typed as PPV-M were widely distributed in the southern, central and eastern regions in the 4 Prunus species. PPV genetic diversity was further assessed by sequencing the (Cter)NIb, full CP and 3’-UTR genomic region (1252 nt) for 15 isolates. Phylogenetic reconstruction confirmed initial strain assignment for the Macedonian isolates with high support values. This work demonstrates the presence of the 3 main PPV strains in the Republic of North Macedonia.