Phaeoviruses present in cultured and natural kelp species, Saccharina latissima and Laminaria hyperborea (Phaeophyceae, Laminariales), in Norway

Phaeoviruses (Phycodnaviridae) are large icosahedral viruses in the phylumNucleocytoviricota with dsDNA genomes ranging from 160 to 560kb infecting multicellular brownalgae (Phaeophyceae). The phaeoviral host-range is broader than expected, not only infectingalgae from the Ectocarpales but also from the Laminariales order. However, despite phaeoviralinfections being reported globally, Norwegian kelp species have not been screened. Molecularanalysis of cultured and wild samples of two economically important kelp species in Norway(Saccharina latissima and Laminaria hyperborea), revealed that phaeoviruses are recurrentlypresent along the Norwegian coast. Moreover, up to three different viral sequences were found inthe same algal individual, one of which does not belong to the Phaeovirus genus and has neverbeen reported before