Molecular characterization of a novel ourmia‐like virus infecting the plant-pathogenic fungus Botryosphaeria dothidea

Abstract Here, we describe a novel ourmia-like virus, Botryosphaeria dothidea ourmia-like virus 3 (BdOLV3), derived from the phytopathogenic fungus Botryosphaeria dothidea strain ZM211299-2 infecting apple shoots in Shandong province of China. The complete genome sequence of BdOLV3 consists of a positive-sense single-stranded RNA (+ ssRNA) segment with a length of 2,650 nucleotides (nt). The sequence contains a large open reading frame (ORF) encoding a putative RNA-dependent RNA polymerase (RdRp) consisting of 673 amino acids (aa) with a molecular mass of 75.53 kDa. This RdRp protein contains eight typical conserved motifs associated with ourmia-like viruses. BLASTp analysis revealed that the RdRp protein of BdOLV3 had the highest similarity (61.98%, and 51.47% identity) to viruses previously identified as Plasmopara viticola lesion associated ourmia-like virus 45, and Magnaporthe oryzae botourmiavirus 7, respectively. Phylogenetic analysis based on the RdRp aa sequence indicated that BdOLV3 is a new member of the genus Epsilonscleorulivirus in the family Botourmiaviridae. This study is the first to report the complete genomic sequence of the genus Epsilonscleorulivirus in B. dothidea.