Characterisation of a novel alphaendornavirus isolated from balloon flower (Platycodon grandiflorus)

The complete genome sequence of a new virus, provisionally named "balloon flower endornavirus" (BfEV), was determined following virus isolation from leaves of a balloon flower (Platycodon grandiflorum) exhibiting severe leaf shrinkage disease in Anhui Province, China. The 15,180-nucleotide genome sequence of BfEV shares 40.52% amino acid (aa) sequence identity and 98% coverage with the polyprotein of Helianthus annuus endornavirus (HaEV). The open reading frame (ORF) encodes a deduced 4,887-aa polyprotein with RNA-dependent RNA polymerase (RdRp), viral helicase (Hel) and glycosyltransferase (GT) domains. Phylogenetic analysis of the amino acid sequences of RdRp places BfEV alongside members of the genus Alphaendornavirus in the family Endornaviridae. To our knowledge, this is the first report of a complete genome sequence of a novel alphaendornavirus identified in balloon flower.