The European race of the ascomycetous species Gremmeniella abietina (Lagerberg) Morelet includes causal agents of shoot blight and stem canker of several conifers in Europe and North America, which are known to host a diverse virome. GaRV6 is the latest and sixth mycovirus species reported within G. abietina. Before its description, one victorivirus and one gammapartitivirus species were described in biotype A, two mitoviruses in both biotypes A and B and a betaendornavirus in biotype B. Possible phenotypic changes produced by mycoviruses on G. abietina mycelial growth have been reported in Spanish mitovirus-free and GaRV6-hosting G. abietina isolates, which had higher growth rates at the optimal temperature of 15 °C, but no other major differences have been observed between partitivirus-like dsRNA and dsRNA-free isolates. In this review, we reappraise the diversity of viruses found in G. abietina so far, and their relevance in clarifying the taxonomy of G. abietina. We also provide evidence for the presence of two new viruses belonging to the families Fusariviridae and Endornaviridae in Spanish isolates.

• Klíčová slova
• Brunchorstia pinea, conifers, dsRNA, evolution, mycovirus, phylogeny, ssRNA,
• MeSH
• Ascomycota virologie   MeSH
• biodiverzita * MeSH
• cévnaté rostliny mikrobiologie   MeSH
• mykoviry klasifikace   izolace a purifikace   MeSH
• nemoci rostlin mikrobiologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Geografické názvy
• Evropa MeSH
• Severní Amerika MeSH

The population genetics of the family Partitiviridae was studied within the European race of the conifer pathogen Gremmeniella abietina. One hundred sixty-two isolates were collected from different countries, including Canada, the Czech Republic, Finland, Italy, Montenegro, Serbia, Spain, Switzerland, Turkey and the United States. A unique species of G. abietina RNA virus-MS1 (GaRV-MS1) appears to occur indistinctly in G. abietina biotypes A and B, without a particular geographical distribution pattern. Forty-six isolates were shown to host GaRV-MS1 according to direct specific RT-PCR screening, and the virus was more common in biotype A than B. Phylogenetic analysis based on 46 partial coat protein (CP) cDNA sequences divided the GaRV-MS1 population into two closely related clades, while RNA-dependent RNA polymerase (RdRp) sequences revealed only one clade. The evolution of the virus appears to mainly occur through purifying selection but also through recombination. Recombination events were detected within alignments of the three complete CP and RdRp sequences of GaRV-MS1. This is the first time that recombination events have been directly identified in fungal partitiviruses and in G. abietina in particular. The results suggest that the population dynamics of GaRV-MS1 do not have a direct impact on the genetic structure of its host, G. abietina, though they might have had an innocuous ancestral relationship.

• Klíčová slova
• Biotype, Brunchorstia pinea, Conifers, Evolutio, Mycoviruses, Partitiviridae,
• MeSH
• Ascomycota izolace a purifikace   virologie   MeSH
• fylogeneze MeSH
• genotyp MeSH
• molekulární evoluce MeSH
• molekulární sekvence - údaje MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• rekombinace genetická MeSH
• RNA virová genetika   MeSH
• RNA-viry klasifikace   genetika   izolace a purifikace   MeSH
• sekvenční analýza DNA MeSH
• sekvenční homologie MeSH
• shluková analýza MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• Kanada MeSH
• Spojené státy americké MeSH
• Názvy látek
• RNA virová MeSH