| As a kind of Chinese traditional medical herb, Sattssurea medusa Maxism belongs to Compositae familia, Saussurea DC.geneus, Subgen Eriocoryne (DC) Hook.f. This perennial herb grow in gravelly soil or meadom at altitude of 4750-5600m in Qinhai ,Gansu ,Sicuan ,Yunnan and Tibet.The poor nutritional condition and killing freeze climate are the features of natural growing environment of Saussurea medusa Maxism. It can germinate at 0癈 and develop at 3-5 C even suffer from chilliness of -21 C.At the fifth or sixth year, it ablooms at July, fruits at August or September. When the seeds are scattered by wind, the plant turn to death.Saussurea medusa Maxism was used by several minorities in China, because it have some special pharmaceutical effects such as detoxification, detumescence, abirritation, antitumor, anti-radiation and anti-ageing etc.But Saussurea medusa Maxism was on the edge of annihilation for being exploited excessively at a long time.still the natural resource of it is hard to meet the increasing need of market .So ths botanical scientist paid more attention to the relationship between protecting this endangered species and producing it's pharmaceutical ingredient. Presently, the scientist have made out some successes by using biotechnology and molecuology, for example, planting out regeneration shoots, culture suspended cell in ferment tank, screening mutant tissue with high content of flavonoids, cloning and sup-expression of key enzyme, restraining derivative pathway by anti-DNA or anti-RNA and inducing genetic transformated hairy root.Agrobacterium rhizogenes (Rhizobiacease) is a kind of Gram-negative bacterium, which contains a big Ri plasmid (200kb)-root inducing plasmid. There are three types of Ri plasmid, mannopine type, cucumopine type and agropine type, according to the type of opine synthesized in transgenic cell. The gene rolA, rolB, rolC and rolD from Ri T-DNA play an important role in hairy root induction in transformed plants, characterized by an abundant proliferation of adventitious roots from the site of infection.The hairy root is originated from single cell and grows quickly without auxin. More interesting, the content of secondary metabolite always increased markedly in hairy root. So the transgenic system by Ri plasmid would be wildly used in plant breeding, plant gene engineering and pharmaceutical element production.In order to establish the genetic transformation system of Saussurea medusa Maxism byAgrobacterium rhizogenes, some work were done .The main results were following:1 establishment of regeneration systemsTwo systems of regeneration from Saussurea medusa Maxim were established without cold treatment.The somatic embryos were induced from callus cultured in MISE for 35 days. The shoots were induced from cotyledon after cultured in MISC 20 days, and from leave which were cultured in MISL .The experiment showed that the carbon and glycine in the medium could help to increase the regeneration rate to 95%. Compared with the regeneration from somatic embryos, the organic regeneration system had some characters such as short period, high efficiency and low abnormal shoot rate. More importently, the content uf total flavonoids in shoot was about 4%, which was 3-4 times of wild type.2 establishment of genetic transformation system by Agrobacterium rhizogenesThe different types of explants (hypocotyls, cotyledon, leaf blade, petiole) were infected by strain R1601 of Agrobacterium rhizogenes. Pre-cultured in the medium MS + 2,4 -D( 1.0 mg/L)+BA (0.2 mg/L) for 2-4d, the plant material were pre-treated in sterile sucrose solution (80-100 g/L) for 1 hour, then quickly dipped into R1601 which had been induced by As (50 mol/L) and proline (250 mg/L) for 30 min. The explants were co-cultured on the same medium for 3-4d in dark after dried by sterile paper carefully. When the co-culture was over ,the materials were washed by sterile water 5-7 times ,then disgermed in liquid MS containing Cef (500 mg/L) for 30min. After cultured in inducing medium MS...
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