title: Population structure of a novel putative mycovirus infecting the conifer root-rot fungus Heterobasidion annosum sensu lato.
abstract: We describe a novel putative mycovirus infecting the conifer root-rot fungus Heterobasidion annosum sensu lato. This virus, designated as Heterobasidion RNA virus 6 (HetRV6), is taxonomically distant from all previously known viruses of Heterobasidion species, but somewhat related to the Curvularia thermal tolerance virus and the Fusarium graminearum virus 4. Based on a population analysis including 35 virus strains from Heterobasidion abietinum, Heterobasidion parviporum, Heterobasidion annosum sensu stricto and Heterobasidion occidentale, HetRV6 showed a considerable degree of geographical and host-related differentiation. The North American and Eurasian virus populations were clearly separated. In Eurasia, we observed cases of discrepancy between virus and host taxonomy, suggesting interspecies virus transfer. HetRV6 was also successfully transmitted between the three European species H. abietinum, H. annosum and H. parviporum. Based on growth rate tests on agar plates and spruce stem pieces, HetRV6 seemed to be cryptic or slightly mutualistic to its host.
authors.affiliation: Finnish Forest Research Institute, Jokiniemenkuja 1, 01301 Vantaa, Finland. eeva.vainio@metla.fi
authors.forename: Eeva J
authors.initials: EJ
authors.lastname: Vainio
authors.forename: Rafiqul
authors.initials: R
authors.lastname: Hyder
authors.forename: Gülden
authors.initials: G
authors.lastname: Aday
authors.forename: Everett
authors.initials: E
authors.lastname: Hansen
authors.forename: Tuula
authors.initials: T
authors.lastname: Piri
authors.forename: Tuğba
authors.initials: T
authors.lastname: Doğmuş-Lehtijärvi
authors.forename: Asko
authors.initials: A
authors.lastname: Lehtijärvi
authors.forename: Kari
authors.initials: K
authors.lastname: Korhonen
authors.forename: Jarkko
authors.initials: J
authors.lastname: Hantula
mesh_terms: D001208:Asia; D001487:Basidiomycota / Q000821:virology*; D003710:Demography; D005060:Europe; D015967:Gene Expression Regulation, Viral; D006239:Haplotypes; D009656:North America; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology; D011110:Polymorphism, Genetic; D012328:RNA Viruses / Q000235:genetics / Q000302:isolation & purification*; D012367:RNA, Viral / Q000235:genetics; D012641:Selection, Genetic; D064028:Tracheophyta / Q000382:microbiology*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D012367:RNA, Viral; D014764:Viral Proteins