Identification and complete genomic sequence of a novel sadwavirus discovered in chrysanthemum (Chrysanthemum morifolium Ramat)

Abstract The complete genomic sequence of a putative novel member of the genus Sadwavirus was determined by high-throughput sequencing of a chrysanthemum from an orchard of Tongxiang Agricultural Science Institute in Tongxiang, Zhejiang province. The complete genome was further confirmed using RT-PCR and the rapid amplification of cDNA ends (RACE) method. The predicted genome of the putative virus was composed of two RNA molecules of 7016 and 6772 nucleotides in length, excluding the poly-A tails. The new virus was tentatively named “chrysanthemum sadwavirus” (ChSV). The Pro-Pol region of RNA1 and the CP region of RNA2 of ChSV shared the highest amino acid sequence identity of 53.01% and 36.40%, respectively, with the corresponding sequences of lettuce secovirus 1(LSV-1). Phylogenetic analysis showed that ChSV clustered in the subgenus Stramovirus (genus Sadwavirus). Taken together, these results suggest that ChSV is a new member of the genus Sadwavirus.