Leaf Anatomy And Molecular Identification Of Medicinal Plants Of Some Mangrove Species In China

Objective: Based on the medical records of 23 kinds of mangrove plants,the microscopic study and molecular level DNA barcode identification of the collected mangrove medicinal plants and their similar plants were carried out to provide scientific basis for the exploitation of the resources of mangrove plants and the further medical research.Methods: Different species of medicinal mangrove plants were investigated and collected,and pharmacognosy methods were used to observe and compare the leaf tissue characteristics of mangrove plants under the optical microscope and scanning electron microscope.According to the molecular phylogenetic theory,the DNA bar code identification technique was used to extract the DNA of the plant base group,the selected nuclear gene ITS2 and the chloroplast P.The psbA-trnH fragment was connected with the carrier,PCR amplification and bi-directional sequencing.The interspecific and intraspecific genetic distance was calculated by software MEGA6.0,and the NJ phylogenetic tree was constructed,and the sequence results of various plants were compared and analyzed.Results:From the analysis of the characteristics of the transverse section of the leaf tissue,the cuticle of the mangrove plant is covered with cuticle.The epidermal cells are different in the number,size and the substance contained in the cells.The mesophyll is well developed and the vascular bundle of the main vein is more developed.The morphological characteristics of leaf epidermis were mainly concentrated on the morphology of epidermal cells,the type of the hanging wall,and the type of stomatal apparatus.The difference between leaf scanning electron microscope is mainly the stratum corneum,wax,and shape of stomatal apparatus.The identification results of DNA barcodes obtained on the molecular level are in agreement with the results of macro botany classification,indicating that the ITS2 sequence is the main sequence and the psbA-trnH sequence can be used as an auxiliary sequence for the identification of mangrove species.Conclusion: This paper provides a new information for the microscopic identification and molecular identification of mangrove species,and provides a reference for further resources development and more accurate medicine for medicinal plants of mangrove plants.