Résumé
This study was aimed to identify and distinguish Metacordyceps liangshanensis recorded by the Sichuan Province Traditional Chinese Medicine Standard from its adulterants and its relative species by combining ITS and COI barcode sequences in order to study the feasibility of this new method. After extracting DNA of 28 species of Cordyceps samples, DNA were amplified and sequenced. And then, ITS and COI sequences were received. Codon-Code Aligner V3.7.1 and Mega 5.0 were used to analyze the variable site and construct the N-J tree. The results showed that the minimum ITS inter-specific K-2P distance was relatively higher than the maximum intra-specific K-2P distance. The inter-specific sequence divergence between M. liangshanensis and its adulterants exhibited high while intra-specific sequence divergence exhibited low. And COI one was the same case. N-J tree of both ITS and COI indicated that same genus belonged together and each species belonged to relatively independent branch. It was concluded that based on the ITS and COI gene, the technology of DNA barcode can be an excellent identification of M. liangshanensis, its adulterants and its relative species. It provided technical support for the further research on species molecular identification and phylogenetics of Cordyceps .