Molecular Identification of Atractylodes Plants Based on ITS2 Sequence / 中国实验方剂学杂志

ABSTRACT

Objective: To identify the genetic relationship of cultivated and wild Atractylodes and its closely related species by using the Internal Transcribed Spacer 2(ITS2)barcode,in order to explore the cultivation origin of A. coreana from Northeast China. Method: Genomic DNAs were extracted from 40 samples of Atractylodes and its closely related species from different cultivated habitats,and 7 samples of wild A. coreana. were also extracted. The ITS2 sequences of these samples were amplified, and bidirectional sequencing was conducted by polymerase chain reaction(PCR). Totally 47 ITS2 sequences were aligned by using MEGA 5.0,5.8S and 28S sequences were removed to obtain the complete ITS2 sequence and build neighbor-joining (NJ) tree. Result: The lengths of ITS2 sequences of all samples were 232 bp. The NJ tree and the secondary structures of ITS2 showed that various varieties could be distinguished obviously except A. chinesis and A. coreana,which showed a good monophyly. The NJ tree showed that cultivated and wild A. coreana can also get together very well. Conclusion: As a DNA barcode,ITS2 sequences can be used to stably and accurately distinguish various varieties of Atractylodes. The relationship between A. chinesis and A. coreana is very close. A. coreana can be considered as a variant of A. coreana in North China. It is recommended to incorporate A. coreana into A. chinesis. The large-scale cultivation of A. coreana may originate from local wild population in Liaoning province,and the provenance may come from Xiuyan and other places in Liaoning province.