Identification of Psammosilene Radix and Its Adulterants by ITS2 Sequence / 世界科学技术-中医药现代化

ABSTRACT

Psammosilene Radix is a famous miao national herb and it is rare and endangered nowadays. However, it is often confused with the root of Silene viscidula. In this study, the ITS2 regions was used to identify Psam-mosilene Radix and its adulterants. All DNA samples of Psammosilene Radix and its adulterants were extracted. The ITS2 regions were amplified and sequenced, and the final sequences were assembled using the CondonCode Aligner. The genetic distances were calculated by kimura 2-parameter (K2P) model and the Neighbor-Joining(NJ) phylogenetic trees were constructed using MEGA5.1.BLAST 1, the nearest distance and phylogenetic tree (NJ-tree)methods were used to assess the identification efficiency of the ITS2 region. Results indicated that the length of ITS2 sequences of Psammosilene Radix w 229 bp, the identification effficiency of ITS2 region using BLAST 1 was 100%;and the maximum intra-specific K2P distance were lower than the minimum inter-specific K2P distance. Additionally, the NJ tree based on ITS2 sequence indicated that Psammosilene Radix and its adul-terants could be distinguished clearly . In conclusion , the ITS2 region as DNA barcodes could identify Psammosi-lene Radix and its adulterants stably and accurately. Furthermore, the application of ITS2 barcode in the identifi-cation of TCM has a good prospective .