اولین گزارش از آلودگی ویروس اف هسته‌دارها (Prunus virus F) در درختان آلبالو و گیلاس کشور

Prunus virus F (PrVF) is a member of the Fabavirus genus in the Secoviridae family. PrVF was first identified and reported from sweet cherry trees in the USA in 2017. Considering the importance of the healthy seedling production programs and in order to investigate the possibility of PrVF presence in the stone fruit orchards, during a survey from 2022 to 2024, several commercial stone fruit orchards and nurseries were visited in Tehran, Alborz, and Qazvin provinces and a total of 183 and 117 leaf samples were randomly collected from sweet cherry (Prunus avium) and sour cherry (Prunus cerasus) trees, respectively. Samples were tested for probable PrVF infection by RT-PCR assay using two primer pairs specific to PrVF. Primer pair PVF1-CAF and PVF1-CAR and primer pair Fab-R2.1808F and Fab-R2.2546R were designed to amplify fragments of PrVF genomic RNA1 and RNA2, respectively. Two DNA amplicons of the expected sizes 457 and 738 bp corresponding to RNA1 and RNA2, respectively, were produced in 14 sweet cherry and 25 sour cherry samples. Nucleotide sequences of the obtained amplicons were determined in three isolates using the Sanger method and compared with available sequences at GenBank using the BLAST tool in the NCBI database. Our sequences showed the highest nucleotide identity (95.3 to 98.4 %) to the previously reported PrVF sequences. This is the first report of PrVF occurrence in Iran. There was no clear relationship between the symptoms and PrVF infection in the tested samples, which indicates the possible latent infection of PrVF in sweet and sour cherry hosts. Observations of the association of PrVF with sweet cherry decline have been reported in the United States, however, details of PrVF pathogenic characteristics, symptoms, and extent of damage in not yet available. Further studies are needed to understand the distribution, frequency, and properties of Iranian PrVF isolates in the stone fruit orchards of the country.