抄録
The small brown planthopper Laodelphax striatellus often immigrates to western part of Japan from eastern China in June. This study examined acquisition rates of rice striped virus and rice black-streaked dwarf virus in adult L. striatellus collected from 29 sites of Kyushu Island shortly after mass immigration of the planthopper in early June 2017. Of 2,582 adults examined, RSV and RBSDV were detected from 15 and 6 adults, respectively. Phylogenetic analyses using nucleotide sequences of nucleocapsid protein (N) gene, non-capsid protein (NCP) gene, and IR3 and IR4 regions of RSV supported the previous findings that N gene divides the RSV strains in east Asia into three genetic clades, Kanto, China-subtype I, and China-subtype II, and all RSV strains collected in this study was classified into China-subtype I. Phylogenetic analyses based on N and NCP genes of RBSDV suggested that RBSDV migrates from China to Japan together with the overseas migration of L. striatellus although further investigation and analysis are needed.
