Complete sequence and genetic characterization of a novel insect-specific reovirus discovered from Laodelphax striatellus.

The small brown planthopper, Laodelphax striatellus (Hemiptera: Delphacidae), is an efficient vector of several economically important plant viruses. In this study, a novel reovirus-like virus was identified in L. striatellus, named Laodelphax striatellus reovirus (LSRV). The complete genome of LSRV was 28,207 nt, comprising of ten segments encoded 11 deduced proteins. All genome segments were conserved with AGUAA at the 5'-terminal and GUUGUC at 3'-terminal and segment-specific inverted terminal repeats. In addition, genomic characteristics and phylogenetic analysis suggested that LSRV was a new member of genus Fijivirus. Importantly, LSRV was widely distributed in various tissues and highest expressed in adult heads. However, LSRV was unable to horizontal replication in rice plants. Moreover, typical profiles of LSRV-derived small interfering RNAs indicated host antiviral RNA interference pathway was involved in LSRV infection. In conclusion, LSRV may be considered as a new species of the genus Fijivirus in the order Reovirales.