Polerovirus is a genus within the Solemoviridae family of plant viruses, characterized by a positive-sense, single-stranded RNA genome. In this study, a new polerovirus, designated as iris polero-like virus 1 (IPLV1), was identified in an iris plant in Iran exhibiting mosaic patterns, yellowing, and dwarfing symptoms. The viral genome, consisting of 5,675 nucleotides, was determined through high-throughput sequencing and subsequently validated by RT-PCR and Sanger sequencing. The genome organization of IPLV1 is consistent with that of other Polerovirus members, containing seven predicted open reading frames (ORFs), namely ORF0– ORF5 and ORF3a. The genome features conserved Polerovirus-specific domains and shares the highest nucleotide sequence identity (56%) with turnip yellows virus (Polerovirus TUYV). Sequence comparisons of IPLV1 gene products with those of its closest relatives revealed amino acid sequence identities below the 90% threshold for species demarcation within the Polerovirus genus, as established by the ICTV, suggesting that IPLV1 represents a novel species within this genus. Phylogenetic analyses based on the near-complete genome sequence, as well as the RNA-dependent RNA polymerase and coat protein amino acid sequences, further supported that IPLV1 is a novel polerovirus. This is the first report of a polerovirus infecting iris plant worldwide.

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