Sequencing and biological characterization of historical cynosurus mottle virus isolates from Germany

We report sequencing of four historical cynosurus mottle virus (CnMoV) isolates, originating from different hosts and locations. The CnMoV genome, ranging from 4417 to 4419 nt, encodes five ORFs. It shares 48.1% nucleotide sequence identity with cocksfoot mottle virus and 69.8% with the recently discovered Poaceae Liege sobemovirus. Phylogenetic analysis supports classification within the genus Sobemovirus. Sequenced CnMoV isolates exhibit 96.4-99.9% identity. Nucleotide substitutions leading to amino acid changes showed no host associations. However, amino acid changes in the coat protein appear to be linked to differences in serological properties. Aphid transmission tests confirmed non-transmissibility, consistent with earlier observations for the English isolate.