Complete genome sequence of a new quadrivirus infecting a member of the genus Thelonectria

A novel dsRNA virus named “Thelonectria quadrivirus 1” (TQV1) was found in a member of the genus Thelonectria (Ascomycota), isolated from a root associated with stem collar necrosis of Fraxinus excelsior L. The complete genome of TQV1 is composed of four segments, each containing a single ORF on the positive sense RNA. The sequence of the 5´ (5´-(C/T)ACGAAAAA-3´) and 3´termini (5´AT(T/G)AGCAATG(T/C)GC(G/A)CG-3’) of dsRNA 1 (4876 bp), dsRNA 2 (4312 bp), dsRNA 3 (4158 bp), and dsRNA 4 (3933 bp) are conserved. Based on its genome organization and phylogenetic position, TQV1 is suggested to be a new member of the family Quadriviridae. This is the first report of a mycovirus infecting a member of the genus Thelonectria. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00705-021-05353-y.