Study On Tissue Culture Of Medicinal Plant Knoxia Valerianoides Thorel Et Pitard

Through the systemic experiments on tissue culture of a rare andendangered medicinal plant, Knoxia Valeranoides Thorel et pitard, an efficientin vitro propagation system was developed in this research. Additionally, a seriesof experiments on manual culture were conducted and some factors affecttingthe transplant survive rate of test-tube plantlets were obtained. It can providesome important references on Knoxia Valeranoides Thorel et pitard tissueculture, rapid propagation, germplasm conservation and manual culture. Themain results of this research are as follows:1. Regard to the tissue culture of Knoxia Valeranoides Thorel et pitard, theoptimum basic medium was MS medium.2. The pathway of adventitious bud differentiation may become the mainpathway on tissue culture to attain the tube plantlets.3. During induction callus and adventitious bud differentiation, the culturalcondition in light is better than in dark.4. The apical-bud was the best explant for the tissue culture of Knoxiavalerianoides Thorel et Pitard.5. 6-BA was beneficial for the callus induction and the subcultrue ofadventitious buds.6. 20 days/generation was favorable for the multiplication of adventitiousbuds and plantlets. The best concentration of sugar on subculture was 20g·L^-1.7. In the subcultrue, it is necessary that 6-BA, NAA and MET should be added in propagation medium at the same time, the optimum combination was6-BA_{2.0mg·L^-1}+NAA_{0.1mg·L^-1}+MET_{0.8mg·L^-1}. The highest buds multiplication timeswas 4.20.8. In the subcultrue, the effect of 6-BA was better than KT obviously.9. In the culture of root induction and sound seedling, the optimal mediumwas 1/2MS medium supplemented with 0.2mg·L^-1 IBA and 1.4mg·L^-1 MET,while NAA doesn't fit for the root induction and sound seedling.10. In the four kinds ABT (ABT₁,ABT₅,ABT₆,ABT₈), the effect of rootinduction in ABT₈ was better than the others, the ABT₁ doesn't fit for the rootinduction.11. The best transplant substrate was peat combined with pearl gravel (1:1).During the 10 days of transplant, we should take care for the tube plantlets, therelatively humidity not be allowed below 85%, the temperature was between15～30℃. It can ensure that the survive rate was up to 85%.12. Supplying 0.07% KH₂PO₄ solution was beneficial for growth of thetransplants in the substrate.