Germplasm Identification Of Dendrobium Candidum In Mount Longhu

Dendrobium candidum is one of the most valuable Chinese herbal medicines and is listed among the top nine Chinese herbal medicines.In recent years,the breeding,variety and active ingredients of Dendrobium candidum have gradually increased.Firstly,the seeds of Dendrobium candidum sampled from Mount Longhu were selected for natural germination in the laboratory and cultivated in a way similar to wild planting.It was found that 1/2MS was showered every day under the basic conditions of vigorous growth of bark and moss.The seedlings of Dendrobium candidum in culture medium are the most naturally sprouted.Secondly,30 samples from Dendrobium candidum in Mount Longhu,Jiangxi Province were selected to identify the varieties.Using the universal DNA barcodes to analyze the 30 samples,six species were identified as the unique species of Mount Longhu.Using the Neighbor-Joining tree in MEGA 5.0 to construct the evolutionary tree of the 30 species,genetic distance was used to determine the genetic relationship between species and the genetic distance between them was found to be very small.Finally,the main species cultivated in Mount Longhu were selected for analysis of active ingredients,the content of polysaccharides in samples was determined by phenol-sulfuric acid method,the content of mannose in samples was determined by high-performance liquid method,and the samples were measured by acid dye method.The content of alkali is determined by Kjeldahl determination of protein content in the sample,and the trace element content in the sample is determined by atomic fluorescence absorption method.It is found that the content of polysaccharides,alkaloids,protein and mannose is better than that of other areas.The content of trace elements is lower than the content requirements of the national pharmacopoeia.