Evaluation of Pesticide Treatment for Control of Rice stripe virus after Mass Migration of Small Brown Planthoppers

Crop Protection Division, National Academy of Agricultural Service, Suwon 441-707, Korea(Received on July 21, 2012; Revised on August 17, 2012; Accepted on August 22, 2012)The small brown planthopper (Laodelphax striatellus) is one of the most important rice pests in Republic ofKorea because it damages rice plants not only by sap-sucking but also by transmitting Rice stripe virus (RSV).Outbreaks of RSV are closely related to outbreaks of the small brown planthopper (SBPH). Therefore, it isvery important to control SBPH for the management of RSV. Mass-migrating SBPH collected by aerial nettraps in June 2011 at Taeanup, Geunheungmyon and Gonammyon in Taeangun were examined for viruscarrier status and effects of the pesticide, ‘Myungtaja’, on the control of RSV. Among 1,217 SBPH trapped,about 7.7% were detected as RSV positive and 4.4% were positive for Rice black streak dwarf virus (RBSDV)by RT-PCR. After the mass migration, pesticide ‘Myungtaja’ was sprayed once or twice on rice fields andcompared to untreated fields. The incidence of RSV was not affected by the frequency of spraying‘Myungtaja’ but was influenced by the time of pesticide treatment. Myungtaja’ treatment within 5−7 daysafter mass migration resulted in the most efficient RSV control, resulting in RSV incidence decreased by87.6% compared to the control. Therefore, we conclude that pesticide spraying for RSV control was mosteffective when it was done within 5−7 days after mass migration.Keywords : Mass migration, Myungtaja, Rice stripe virus, Small brown planthopper 국내 벼에 발생하는 바이러스는 벼줄무늬잎마름바이러스(Rice stripe virus, RSV), 벼검은줄오갈바이러스(Riceblack streaked-dwarf virus, RBSDV)와 벼오갈바이러스 (Ricedwarf virus, RDV) 3종이 보고되고 있다(Kim 등, 2008).RSV는 Tenuivirus에 속하는 사상형 바이러스이고, RBSDV와 RDV는 Reoviridae에 속하는 구형 바이러스이다(Toriyama, 2000). RSV와 RBSDV는 애멸구(Small BrownPlanthopper, SBPH)에 의하여 영속 전염하는 바이러스이다. RSV에 감염된 벼는 유묘에서 감염 후, 일주일 또는이주일정도 지나면 잎에 모자이크 증상이 나타나고 줄기