Study On Regeneration System Of Taxus. Mairei And Taxus. Media

Taxol is a new anti-cancer drug be extracted from Taxus plant. Taxol has high prices because of lack resources, therefore, Taxus is famous as "Golden tree". Taxus plant is growing with symbiotic fungi and growing slowly. It's seeds turn ripen need a long period, this take some difficulties for breeding and planting Taxus in large scale. At present, used plant tissues or organs in field as the materials to study on plant regeneration is very less. There is no coverage on induced indefinite embryo. This paper used Taxus.media and Taxus.mairei as the tested materials to make a systematic study on the Taxus explants disinfection, callus induction and differentiation, axillary bud proliferation and regeneration system, root in vitro culture, protein analysis, PPO and POD isozymes analysis. The results are showed as following.1. Study on disinfecting through the disinfectant, disinfecting methods, disinfecting times, growing age and the position of materials. The results showed, the explant materials immerse in 75 percent ethanol after about 15 seconds and then using 0.2 percent mercuric chloride disinfecting 5 by 5 minutes is the best disinfecting program.2. The axillary buds and stems which are in the active growth phase and on the upper canopy branches or growing in this year are the best materials for callus induction. The suitable callus induction medium of Taxus.mairei and Taxus.media is B₅ added with NAA 1.0 mg / L, IBA 1.0 mg / L, BA 0.1 mg / L and GA3 1.0 mg / L. GA3 has a certain role play on callus proliferation and inhibit the browning. The callus of Taxus.mairei cultured on B₅ medium which added with IBA 0.2 mg / L and BA 0.1 mg / L differentiated fake ovule.3. Stem explants can germinate a number of axillary buds. The axillary buds which on the morphology top with a high degree of lignification explants are first germinated. But the axillary buds which on the morphology bottom with a low degree of lignification explants are germinated at first. The optimal medium of axillary buds germination of Taxus.mairei is DCR which added with IBA 0.1 mg / L and BA 0.05 mg / L, the germination rate is 97.5%. The optimal medium of axillary buds germination of Taxus. media is DCR which added with NAA 0.5 mg / L and BA 0.05 mg / L, the germination rate is 84.9%.4. The suitable rooting medium of Taxus.mairei is 1 / 2 DCR which added with IBA 0.5 mg / L and NAA 0.2 mg / L and Taxus. media is 1 / 2 DCR which added with IBA 0.2 mg / L and NAA 0.5 mg/L.5. The seedlings of Taxus.mairei and Taxus.media planted in the yellow soil mixed with sand by 2:1 ratio, at 25 temperature, upon 75 percent humidity, the survival rate were 90.1% and 87.5%.This is resolved the difficult problems of Taxus plantlets rooting.6. The suitable medium of root cultured in vitro of Taxus.mairei is the improved White added with IBA 0.2 mg / L and Taxus.media is the improved White added with 0.5 mg / L.7. The proteins and PPO, POD isozymes bands of Taxus.mairei and Taxus.media have significant differences. The bands number of proteins and PPO isozymes are changed toward less, more and less as following with growth and development of plantlets. The bands number of proteins and POD isozymes reduced, but PPO isozymes bands number increased during the senescenced callus which induced by stem explants of Taxus.mairei. The callus browning is positive correlation to this.