ABSTRACT
As a treasure of traditional Chinese medicine culture,Dao-di herbs are famous for their high quality and good effect.However,traditional characteristics of Dao-di herbs and their producing areas are mostly confined to qualitative description,lacking objective evaluation indicators. Numerical taxonomy,which uses mathematical methods to improve the research of taxonomy from qualitative description to quantitative comprehensive analysis,is objective and accurate,so is widely used in the field of biology and medicine.This paper reviews the concept and main research fields of numerical taxonomy,and summarizes its application status and development prospects in the study of Dao-di herbs and characteristics of production areas,in order to lay the foundation for the objectification and standardization of Dao-di herbs.
Subject(s)
Drugs, Chinese Herbal , Classification , Reference Standards , Medicine, Chinese Traditional , Plants, Medicinal , ClassificationABSTRACT
Objective To determine the taxonomic position of medically important gamasid mites and to compare numerical taxonomy with the traditional systematics in the classification of gamasid mites. Methods Based on hierarchical cluster analysis, numerical taxonomy was applied to study fifty-seven species of medically important gamasid mites. Results The results of cluster analysis based on squared euclidean distance showed that Hirstionyssus Fonseca and Echinonyssus Hirst should be separated from Laelapidae Berlese and formed an independent family. The taxonomic position of the remaining species remains the same as those in the traditional systematics. Conclusion Numerical taxonomy can objectively reflect the taxonomic position of the medically important gamasid mites. The result of classification by numerical taxonomy is consistent with traditional systematics for gamasid mites.
ABSTRACT
A total of 25 fast-growing rhizobium isolates from variety of legumiuous plants in Hainan Province, a tropical region of China, and 7 representative strains of genera Rhizobium, Sinorhizobium and Agrobacterium were characterized by numerical taxonomy. The results indicated that rhizobium isolates from Hainan were taxonomically heterogenous. At thesimilarity level of 70%, 13 strains from Hainan formed a distinct group which could use wider range of carbon and nitrogen sources, and were more resistent to antibiotics and chemicals than known rhizobium species. 2 strains could not fall into any group, and the others fell into different known species respectively. There were no correlations between hosts and the taxonomic positions of their symbionts. The rhizobium isolates from the same host genus or speceis could fall into different groups.
ABSTRACT
24 strains obtained from root nodules of Psoralea corylifolia, Pueraria lobata, and Campylotropis macrocarpa of Yunnan province were studied with numerical taxonomy and 16S rDNA PCR-RFLP. Results of numerical taxonomy indicated that all strains included 10 reference strains were divided into 3 groups at 84% similarity. Group III is an unknown group with no reference strains. Group I is slow-growing kind, and group II fast and middle-slow-grower. The dendrogram derived from 16S rDNA PCR-RFLP showed that all strains divided into five phylogenetic branches at the similarity of 70%. They are branches I and V with no reference strains, Agrobacterium-Sinorhizobium-Rhizobium, Mesorhizobium and Bradyrhizobium. Not all results of numerical taxonomy are accord with 16S rDNA PCR-RFLP, and 2 strains at the same group with A. tumefaciens IAM13129T.
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strains of fast-growing rhizobia isolated from Chinas western (mainly from Qinghai province),and 4 representative strains were compared by performing numerical taxonomy. 132 phenotypic characteristics were analyzed. The results of numerical taxonomy constructed a dendrogram. It shows that all the strains examined clustered into five phena at a similarity level of 79%. 16S rDNA PCR-RFLP were applied to 57 rhizobial strains (among the 61 strains) and 10 reference strains. The 16S rDNA-RFLP analysis described 20 different genotypic characteristics and form one dendrogram. For some large groups, the results of 16S rDNA-RFLP were agreement with that of numerical analysis of phenotypic characteristics.
ABSTRACT
Twenty nine moderately halophilic bacteria isolated from salt lakes in Xinjiang Region were compared with nine reference strains of relative species by performing a numerical analysis of 112 phenotypic characteristics. All the new isolates are Gram negative and can grow on the media containing 0～25% NaCl. The results showed that all tested strains were clustered into 2 phena at 76 % similarity level. Phenon I was composed by 25 new isolates strains,and phenon II included 9 reference strains and 4 new lsolated strains. Most of the new isolated strains were clusted into 3 subphena at 86 % similarity level. There were 10 new isolated strains in subphenon 1, 8 new isolated strains in subphenon 2, and 1 new isolated strain and 5 reference strains were included in subphenon 3. The results indicated that there were great differences between the new isolates and the reference strains.