Analysis On Genetic Diversity Of Radix Astragali By ISSR Marker

Radix Astragali belongs Leguminosae, Astragalus which can be used as medicine in its root. It has two kinds of plants:Astragalus Mongholicus(Astragalus membranaceus (Fisch.) Bge.var. Mongholicus (Bge.) Hsiao) and Astragalus membranaceus(Astragalus membranaceus (Fisch.)Bge.). Radix Astragali was a traditional Chinese herbal medicine since2000years ago. Now, with the development of the science and the pharmacological research, Radix Astragali is not only for clinical medicine, but also for using in the diet and health aspects. The extending of its officinal scope makes the requirement of market enlarged. At present, the wild Radix Astragali resources in our country has been nearly exhausted, and the cultivated Radix astragali becomes the new important force. But the cultivated Radix Astragali often suffers from intraspecific variation, unstable quality and other issues. In addition, whether wild Radix Astragali or cultivated Radix Astragali, will be affected by the origin, age and environmental conditions in the quality and efficacy. Studying the genetic diversity of Radix Astragali using the molecular markers not only can provide theoretical support for the variety, quality identification, but also can provide a reference for the conservation of wild Radix Astragali. It has potential economic benefits.In this study, the main results of genetic diversity analysis on the Radix Astragali by using ISSR molecular marker technology are as follows:1. Builded and optimized ISSR-PCR reaction system of Radix Astragali by single factor experiment. The results show that the best reaction system is a20μL volume ISSR-PCR system with DNA template of6.0ng/μL, dNTPs of0.03mmol/L, TaqDNA polymerase of0.05U/μL, primer of0.80mmol/L2.A total of35primers were screened from100ISSR primers which published by Columbia University when studied the genetic diversity of two populations of Radix Astragali,25primers among them with polymorphism, while10were monomorphic, the PPB was71.4%.273amplified bands were obtained after detected183Radix Astragali samples using25polymorphic ISSR primers, and213bands were polymorphic bands among them, the PPB was78%; The average value of amplified bands were10.9for each primer and the number varied from4to20. 3. Analysis on genetic diversity of different kinds of Radix Astragali, it was the results that the level of genetic diversity in A. membranaceus (h:0.3109;I:0.4657) was slightly lower than A. Mongholicus (h:0.3364;I:0.4969). Analysis on genetic diversity of3wild populations and3cultivated populations of A. Mongholicus, it was the results that the level of genetic diversity of wild populations{h:0.2207;I:0.3247) was lower than cultivated populations(h:0.2773;I:0.4102). The result of sort of nine provinces about genetic diversity level of A. membranaceus was:Inner Mongolia> Heilongjiang> Ningxia> Shandong> Hebei> Gansu> Jilin> Liaoning> Shaanxi; The result of sort of five provinces about genetic diversity level of A. Mongholicus was:Shanxi> Inner Mongolia> Hebei> Gansu> Shaanxi.4. Analysis on genetic differentiation of A. Mongholicus and A. membranaceus from different habitats.. The results showed that, the coefficient of gene differentiation among A. Membranaceus populations (Gst:0.5366; Nm:0.4318) was more high than A. Mongholicus (Gst:0.3890; Nm:0.7852). In the analysis on genetic differentiation of wild and cultivated populations of A. Mongholicus, the result showed that the genetic differentiation of wild populations (Gst:0.2010; Nm:1.9871) was lower than the cultivated populations (Gst:0.2220; Nm:1.7518), the genetic differentiation of wild populations come from mutation or drift, the result of cultivated population may be due to the different seed sources, else.5. Using UPGMA to cluster the A. membranaceus of9habitats and A. Mongholicus of5habitats by NTSYS analysis. A. membranaceus were divided into4groups in0.80:Jilin, Liaoning, Shandong and Hebei, Heilongjiang belonged the first group, Ningxia, Gansu belonged the second group, Inner Mongolia was alone the third group, Shaanxi was alone the final group; Clustered the A. Mongholicus into3groups in0.80:Shanxi, Inner Mongolia belonged the first group, Hebei was alone the second group, Shaanxi, Gansu belonged third groups. Overall analysis, A. Mongholicus and A. membranaceus from7habitats: Shanxi, Inner Mongolia, Shandong, Heilongjiang, Hebei, Jilin, Liaoning gathered as the one group, A. Mongholicus and A. membranaceus from3habitats:Ningxia, Gansu, Shaanxi gathered as the other groups. It showed that different origin of tested materials of Radix Astragali was the biggest factors,then varieties.