Development of Polyclonal Antibodies and a Serological-Based Reverse-Transcription Loop-Mediated Isothermal Amplification (S-RT-LAMP) Assay for Rice Black-Streaked Dwarf Virus Detection in Both Rice and Small Brown Planthopper

Rice black-streaked dwarf virus (RBSDV) infects rice and maize, and seriously affects rice yields in main rice-producing areas. It can be transmitted via small brown planthopper (SBPH: Laodelphax striatellus Fallén). To more rapidly, sensitively, and highly throughput diagnose RBSDV in the wild condition, we first purified the recombinant His-CP^RBSDV protein, and prepared the polyclonal antibodies against the His-CP^RBSDV protein (PAb-CP^RBSDV). Based on the PAb-CP^RBSDV, we developed a series of serological detections, such as Western blot, an enzyme-linked immunosorbent assay (ELISA), and a dot immunoblotting assay (DIBA). Furthermore, we developed a serological-based reverse-transcription loop-mediated isothermal amplification assay (S-RT-LAMP) that could accurately detect RBSDV in the wild. Briefly, the viral genomic dsRNA together with viral CP were precipitated by co-immunoprecipitation using the PAb-CP^RBSDV, then the binding RNAs were crudely isolated and used for RT-LAMP diagnosis. Using the prepared PAb-CP^RBSDV, four serology-based detection methods were established to specifically detect RBSDV-infected rice plants or SBPHs in the wild. The method of S-RT-LAMP has also been developed to specifically, high-throughput, and likely detect RBSDV in rice seedlings and SBPHs simultaneously. The antiserum prepared here laid the foundation for the rapid and efficient detection of RBSDV-infected field samples, which will benefit for determination of the virulence rate of the transmission vector SBPH and outbreak and epidemic prediction of RBSDV in a rice production area.