Analysis of Zingiberaceae in E'mei Area Using ITS2 Sequences / 中国实验方剂学杂志

ABSTRACT

Objective: To evaluate the use of ITS2 sequences as DNA barcode to identify the Zingiberaceae medicinal plants from E'mei area. Method: The genomic DNAs were extracted from 43 Zingiberaceae medicinal plant samples from Sichuan E'mei area. The ITS2 sequences of these samples were amplified and bidirectionally sequenced by PCR. 40 ITS2 sequences were downloaded from the GenBank,and then the interspecific and intraspecific genetic distances were calculated and analyzed by using MEGA 6.0 to construct Neighbor-joining (NJ) tree; TAXON DNA software was also used to analyze intraspecific and interspecific variations and barcoding gaps. The differences in secondary structure of the ITS2 sequences were predicted and compared. Result: The minimum interspecific distance in Zingiberaceae samples was greater than the maximum intra specific distance,with obvious barcoding gap. The NJ tree showed that the samples were clustered into five different branches,Alpinia,Curcuma,Globba,Hedychium,and Zingiber respectively,and further cluster into sub-branches. Significant differences were also present in the secondary structures of ITS2 between different samples. Conclusion: ITS2 sequences as DNA barcode can be used to conduct accurate and rapid identification of the Zingiberaceae plants and clearly figure out the phylogenetic relationship among them,providing guidance for the study of the distribution of medicinal plants of this genus,as well as theoretical basis for the quality control,medication safety and rational development of Zingiberaceae medicinal plants in E'mei area.