Identification of Codonopsis Radix and Its Adulterants Using the ITS/ITS2 Barcodes / 世界科学技术-中医药现代化

ABSTRACT

The ITS/ITS2 barcodes were used to simply and effectively identify Codonopsis Radix and its adulter-ants. In this study, ITS (internal transcribed spacer of unclear ribosomal DNA) regions were amplified using PCR (polymerase chain reaction) from thirty-three samples of Codonopsis Radix and ITS2 regions were obtained from the ITS sequences using the hidden Markov model (HMMer)-based annotation methods. The sequences of ITS/ITS2 regions were aligned and the genetic distances were computed by MEGA5.0. Species identification efficiency of ITS/ITS2 sequences were evaluated using BLAST1 and nearest distance methods. The results indicated that The sequences lengths of ITS regions of Codonopsis Radix were 654-655 bp, and the lengths of ITS2 regions were 239 bp. The intraspecific genetic distances among Codonopsis Radix were obviously lower than the interspecific genetic distance between Codonopsis Radix and its adulterants. Therefore, ITS/ITS2 regions can stably and accu-rately distinguish Codonopsis Radix and its adulterants.