EN
Iris belongs to the Iridaceae family. It is one of the most important pharmaceutical and ornamental plants in the world. To assess the potyvirus incidence in natural resources of iris plants in Iran, Antigen Coated-Plate ELISA (ACP-ELISA) was performed on 490 symptomatic rhizomatous iris leaf samples, which detected the potyvirus in 36.7% of the samples. Genomic 3’ end of one mechanically non-transmitted potyvirus isolate, comprising a 3’ untranslated region (390 bp) and C-terminus of the coat protein (CP) gene (459 bp), was amplified by reverse transcription polymerase chain reaction (RT-PCR), which was ligated into pTG19-T vector. The nucleotide sequence of amplicons was compared with related sequences, using Blastn software available at NCBI GenBank, and showed the highest similarity with Iris severe mosaic virus (ISMV) isolates. The nucleotide and deduced amino acid sequence of the CP C-terminus region was more than 83% identical with other ISMV isolates, therefore this isolate was designated as ISMV-Ir. This new ISMV isolate is closely related to the Chinese ISMV-PHz in phylogenetic analysis, based on the partial nucleotide and deduced amino acid sequence of the CP region. This is the first report of ISMV occurrence on Iris spp. in Iran.