[Identification of moutan cortex and its adulterants by ITS2 sequence]

To explore a new method to identify Moutan Cortex to guarantee its safe use, internal transcribed spacer 2 (ITS2) sequence was used to identify Moutan Cortex and its adulterants. DNA was extracted and target fragments were amplified. Sequences were analyzed and assembled by CodonCode Aligner V3.7.1. Genetic distances were computed and phylogenetic tree was constructed based on kimura 2-parameter (K2P) model by MEGA 5.0. The length of the 20 ITS2 sequences of Moutan Cortex from nine different places is 227 bp, and no variation site was detected. The maximum inter-specificK2P distance of Moutan Cortex is 0, the minimum intra-specific K2P distance is 0.041, the average intra-specific K2P distance is 0.222. According to NJ analysis, Moutan Cortex from different places can get together as one branch with bootstrap support values 99%, which indicates Moutan Cortex can be easily distinguished from its adulterants. Using ITS2 sequence can accurately identify Moutan Cortex and its adulterants, it is an effective supplementary to traditional identification methods.