PCR-RFLP Discrimination between Okinawa and Ogasawara Strains of the Sweet Potato Weevil, Cylas formicarius (Fabricius)

Abstract

To establish a simple method for discriminating Okinawa and Ogasawara strains of the sweet potato weevil, Cylas formicarius, about 560 bp of the internal transcribed spacer-1 (ITS-1) region of the ribosomal DNA (rDNA) of C. formicarius was collected from several islands of Okinawa Prefecture and Ogasawara Islands and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The 345 weevils collected in Okinawa and Ogasawara were discriminated correctly by the RFLP patterns with the restriction enzyme RsaI. The results suggest that C. formicarius originating from Ogasawara Islands is an effective genetic marking strain for an eradication project using the sterile insect technique implemented by the Okinawa prefectural government.