Phragmivirus, a new genus within the family Potyviridae

The plant-infecting virus family Potyviridae was previously formed by 12 genera, consisting of 249 virus species, with the majority of these classified in the largest genus, Potyvirus. Potyvirids are viruses with a ssRNA genome packaged in long filamentous particles. While members of the genus Bymovirus have bipartite genomes, members of the remaining genera have monopartite genomes. All viruses in the family have a genome-linked protein (VPg) present at the 5' terminus of the genome, and all but celery latent virus (genus Celavirus) have a polyadenylated tail at the 3' end. The members of the 12 genera are differentiated by genomic sequence identity, various functional motifs, and biological factors such as the type of the transmission vector and host range. Demarcation criteria for a new genus include < 46% nucleotide sequence identity to potyvirids of other genera. Here, we report the new genus Phragmivirus within the family Potyviridae, which has been accepted by the International Committee on Taxonomy of Viruses, becoming the 13th genus in the family. The genus Phragmivirus is represented by two virus species (Phragmivirus phragmii and Phragmivirus spartinae). Complete genome sequences are available for both members, namely, common reed chlorotic stripe virus (CRCSV) and Spartina mottle virus (SpMV), respectively. The new genus name is derived from the botanical name of the host of CRCSV, Phragmites australis. The genome sequences of CRCSV and SpMV isolates resemble those of members of the genus Potyvirus but lack typical conserved aphid-transmission motifs.

Author A.K.I.-N. is a CNPq fellow and received the grant CNPq-Universal 404174/2023-0. R.J. is funded by USDA-ARS Research Project 8020-22000-052-000-D. J.F.K. has received research support from the Plant Health Initiative and Sustainable Farming program, funded by the CGIAR trust fund (https://www.cgiar.org/funders/). F.L. acknowledges that part of this work was funded by the National Key R&D Program of China (2022YFD1400700). The work of J.J.L.-M. is supported by project PID2022-139376OB-C33, funded by MICIU/AEI/10.13039/501100011033 and by FEDER, UE, and by the CERCA Program, Generalitat de Catalunya, Spain. K.M. acknowledges research support from the Research Council of Finland, grant number 1363204. K.O. was in part funded to undertake this work by the Japanese Society for the Promotion of Science KAKENHI grant Number 21K05601. L.R. acknowledges that part of this work was granted by the European Commission – NextGenerationEU, Project SUS-MIRRI.IT "Strengthening the MIRRI Italian Research Infrastructure for Sustainable Bioscience and Bioeconomy”, code no. IR0000005.

Peer reviewed