Two novel totiviruses in the white-backed planthopper, Sogatella furcifera

There is little information about commensal viruses in the white-backed planthopper, Sogatella furcifera, although it is an important agricultural insect. Here, two novel double-stranded RNA viruses related to the viruses in the family Totiviridae were identified using next-generation sequencing and tentatively named Sogatella furcifera totivirus 1 and 2 (SfTV1 and SfTV2). Their complete genomes consist of 6310 and 6303 nt, respectively, showing typical genomic features with viruses in the family Totiviridae. Identity, phylogenetic and conserved sequence analyses showed that SfTV1, SfTV2 and three other insect viruses may form a proposed novel genus of the family Totiviridae. Vertical transmission of the two viruses was highly efficient, and they were detected in all insect tissues and developmental stages, with the highest titres in the adult and in the haemolymph and reproductive organs. To our knowledge, this is the first report of viruses in the family Totiviridae found in a hemipteran insect.