Abstract:

The rDNA internal transcribed spacers （ITS） of Fallopia multiflora （F. multiflora） and its frequent adulterants, such as Fallopia multiflora var. cilliinerve, Pteroxygonum giraldiiwere and Cynanchum auriculatum, were sequenced and analyzed. The results show that in the ITS1 region, the divergences between F. multiflora and the three adulterants are respectively 6.91%, 18.10% and 42. 20%, while in the ITS2 region, the divergences are respectively 10. 00%, 19.40% and 43.90% ; and that the intraspecies ITS1 and ITS2 divergences of F. multi- flora are 0. 00% -2. 13% and 0. 00% -1.03% , respectively. Based on the divergences, a endonuclease Nsb I restriction site specific for F. multiflora was detected in the ITS2 region and was used for PCR-RFLP （Polymerase Chain Reaction and Restriction Fragment-Length Polymorphism） analysis. It is found that the PCR product from F. multiflora rDNA ITS can be cleaved by Nsb I into two fragments of about 531 bp and 109bp, while that from the adulterants cannot be cleaved, and that the PCR-RFLP map still retains the undigested original rDNA ITS pattern. It is thus concluded that the proposed PCR-RFLP method is effective in discriminating F. multiflora from its adulterants.

Key words: Fallopia multiflora, molecular identification, rDNA internal transcribed spacer, PCR-RFLP