Complete genome sequences of two iflaviruses from the brown planthopper, Nilaparvata lugens

The complete genome sequences of two new iflaviruses (genus Iflavirus, family Iflaviridae) were determined. These viral sequences were first identified in RNA-seq contig sequences of Nilaparvata lugens in two distinct colonies: Izumo and Kagoshima. The accuracy of the contig sequences of the two viruses was verified by restriction enzyme digestion of RT-PCR products from viruliferous insects. RT-PCR of RNA extracted from honeydews after viruliferous insect feeding detected the expected viral products, which suggested that viruses were excreted into the honeydews by the insects. Since we previously designated a similar iflavirus as "Nilaparvata lugens honeydew virus 1", the two new viruses have been tentatively named "Nilaparvata lugens honeydew virus 2" and "Nilaparvata lugens honeydew virus 3". The identity of the putative amino acid sequences of the capsid proteins of these viruses met the criterion for iflavirus species demarcation. Therefore, these two viruses are suggested to be members of distinct species in the genus Iflavirus.