A novel alternavirus with three dsRNA segments from Fusarium pseudograminearum, the pathogen of Fusarium Crown Rot in wheat

Abstract

Abstract Three dsRNA sequences were detected from the Fusarium pseudograminearum strain CF14029, a pathogen causing Fusarium Crown Rot in China. Characterization and sequencing analyses confirmed that these dsRNA sequences originated from the same virus. The virus consists of three dsRNA segments: dsRNA1 (3,560 nt in length) encoding an RNA-dependent RNA polymerase (RdRp), dsRNA2 (2,544 nt in length), and dsRNA3 (2,478 nt in length) which encodes a coat protein (CP). Phylogenetic analysis based on the RdRp and CP amino acid sequences revealed a high similarity of this virus with alternaviruses isolated from other Fusarium fungi of the genus Alternavirus within the family Alternaviridae. As a novel member of the Alternavirus genus, this virus is provisionally named Fusarium pseudograminearum alternavirus 1 (FpgAV1). Similar to other alternaviruses in Fusarium fungi, the positive-sense strand of each genomic dsRNA of FpgAV1 possesses a poly(A) tail and a distinctive 5'-terminal nonamer sequence (5’-GGC TGT GTG-3’). This study represents the first comprehensive description of the genomic sequence of an Alternavirus identified in F. pseudograminearum.