The Study On DNA Molecular Identification Of 12 Kinds Of Common Medicinal Pteridophytes In Lushan Region

Traditional Chinese medicine is a cultural treasure which is the experience of thousands of years of summarizing the people of ancient China.The status of Chinese herbal medicines in traditional Chinese medicine is particularly important.The authenticity of Chinese herbal medicines is the most important aspect of Chinese medicines.There are 2600 kinds of pteridophytes in China,of which one-third of them can be used for medicinal purposes.Surprisingly,there are 121 medicinal pteridophytes in the Lushan region.However,even experienced Fernist are very troublesome in identifying pteridophytes because the traits of the pteridophytes are similar between the same genus.But,researchers can quickly and accurately identify and classify fern species using the DNA Barcoding Technology.In this experiment,the medicinal pteridophytes common in the Lushan region were used as research objects to discuss whether the DNA barcoding technique could be used for the identification of medicinal pteridophytes.Objectives:In the research,12 species of medicinal pteridophytes species and their closely related species in Lushan region were quickly and accurately identified by DNA barcode technology.The feasibility of verifying DNA barcodes for plant identification provides a theoretical basis for the subsequent development and utilization of medicinal pteridophytes in Lushan region.Methods:In this study,samples of common medicinal pteridophytes were selected in non-artificially damaged or non-attraction areas of Lushan Mountain.Then the plant samples were approached to DNA extracting,PCR,purifying and sequencing.The obtained results were compared using CodonCode Aligner V After stitching,Clustalx1.8 alignment error.After expanding the samples,using Clustalx 1.8 for compare analysis,build the kmura-2-parameter model Neighbour-Joining trees and Maximum Likelihood trees with MEGA 7.0,and calculate the relevant data.Finally,use the Basic Local Alignment Search Tool to calculate the sample support rates.Results:1.By using the psbA-trnH+rbcL sequences,the success rates of PCR amplification and sequencing of the 24 experimental medicinal pteridophytes in the12 species of Lushan was 100%.2.Based on the psbA-trnH+rbcL sequences,Neighbour-Joining trees and Maximum Likelihood trees of common medicinal pteridophytes in the Lushan region were constructed.These trees were established under the Kmura-2-parameter model.The experimental samples of 12 species of plants can be clustered on the same branch with the same species of their network,and can be distinguished from their related species.All branches support rates reached more than 50%.3.For the constructed Neighbour-Joining trees and Maximum Likelihood trees,the intraspecifices and interspecies genetic distances were calculated based on the Kmura-2-parameter model.The intraspecific genetic distance of all species was less than the minimum interspecies genetic distance.4.The results obtained were searched by the Basic Local Alignment Search Tool,and the consistency rate for the same species of the experimental samples was above99% as compared with the network samples.Conclusion:In this paper,12 species of common medicinal pteridophytes in Lushan were identified by using psbA-trnH sequence and rbcL sequence.The identification results are the same as the traditional identification method,which reflects the feasibility of using DNA barcode sequences to identify fern species.The experimental results obtained in this study can provide a theoretical basis for the subsequent analysis,identification,development and utilization of medicinal pteridophyte in Lushan region.