Abstract: Rice stripe virus(RSV) and Rice blackstreaked dwarf virus(RBSDV) are 2 important rice viruses which are transmitted by small brown planthopper (Laodelphax striatellus) and cause severe loss for rice production in China. Rapid and reliable detection of the 2 viruses in L. striatellus is a key issue for the control of these diseases. In this study， two sets of primers that are specific for RSV RNA3 and RBSDV S10 were designed， and multiple one step RTPCR method was established for rapid detection of RSV and/or RBSDV in L. striatellus through optimized annealing temperature and cycles of PCR conditions. Comparison of one step and two step RTPCR indicated that both methods can effectively detect RSV and/or RBSDV in L. striatellus and the result of two step RTPCR was slightly better than that of one step. Serial dilutions assay showed that the sensitivity of one step RTPCR method can detect the concentration as low as 0005 ng·μL-1， which is completely enough for the identification of viruses in single planthopper. Finally， multiple one step RTPCR was applied to detect RSV and/or RBSDV in single insect for 200 planthoppers which further confirmed specific， sensitive and timesaving．

Key words: Laodelphax striatellus, Rice stripe virus, Rice blackstreaked dwarf virus, RTPCR