Study On Tissue Culture And Element Affecting Synthesis Of TFM In Metasequoia Glyptostroboides Hu Et

Metasequoia glyptostroboides Hu et is a rare relict plant in the word which belongs to Metasequoia. The discovery of Metasequoia glyptostroboides was regards as one of the most important discoveries in botany field in 1940s and it was considered as "the living fossil plants". The pharmacological researches on TFM (total flavonoids of metasequoia) show that TFM possesses many pharmacological functions as in anti-arrhythmia and cardiac hypertrophy, and it has a prospective foreground for use in curing cardiovascular diseases. Therefore, it has been widely regarded as a sort of medicinal plant. By using the stems with auxiliary buds and stem tips as explants, this paper mainly explored the best hormone ratio, and studied the influence of cultivating process. Meanwhile, the relations between TFM accumulation and the ecological conditions are studied in this thesis.Major research results were as follows:1. The aseptic system was established:As the time of disinfection extended, the infection rate was reduced, but the browning rate was enhanced. Tests revealed that explants was dipped in 75% alcohol for 10 seconds, and then soaked 8 minutes by 0.2% HgCl2. Then the pollution rate was 12.3% and the browning rate was 39.7%. Results indicated the significant difference at 1% level.2. Anti-browning research:In tissue culture of explants, the phenomenon of turning brown was serious. Adding additives could lower the browning rate at relatively level. Studies show that the treatment with AC 0.9g/L were the best, the browning rate individually contained 25.9% and the percentage of germination kept at a high level(21.5%).3. Callus formation and differentiation:Design orthogonal tests, most explants could develop callus under different kind and different concentration of hormone. Study on stems culture and fast propagation showed that the best initial medium differentiation of adventitious bud are MS+2,4-D2.0 mg/L+NAA3.0 mg/L+6-BA 1.5mg/L, MS+NAA 0.2 mg/L+6-BA 1.5 mg/L4. Above three standards including the rooting, the root number, the root length, the result indicated that its optimal culture media of taking root are MS+NAA3.0 mg/L +IAA0.1 mg/L respectively. Root striking rate could be above 18.8%, the number of root would up to 45 and the numerical mean length could be 2.56cm.5. Elements affecting synthesis of TFM:With the orthogonal design, analysis showed that the TFM accumulation would be most affected by light application time followed by incubation temperature and concentration of sucrose. They affected the synthesis of TFM significantly. The optimum condition of TMF accumulation:blue light application time 8 h/d; incubation temperature 20℃; concentration of sucrose 50 g/L.