Studies On Tissue Culture System Of Sapium Sebiferum Roxb.

Sapium sebiferum Roxb is a kind of Euphorbiaceous, oil-yielding tree. The species is highly valued for its waxy fruit with rich lipin, which can be used as the sources of edible oil, industrial oil and power oil, and be recognized as a renewable energy. The search for renewable energy is currently one of the world's most important issues. Therefore, S. sebiferum Roxb as a sort of renewable energy plants has been widely regarded. Nowadays, the problem deadly be resolved is that cultivating a large number of seedlings, and breeding a mass of high-quality seeds of Sapium in a rapid and economic way. In this paper, by researching the stems with auxiliary bud, young stems and leaves of explants, we mainly explored the best hormone ratio of the cultivating explants, and studied the cultivating process and the influencing factors of the stems with axial buds in no vaccine system systematically. The main results were as follows:The optimum sterilizing method is different for a variety of explants in the primary culture. disinfected with 70%ethanol for 30 s and with 0.1 %HgCl₂ for 8 min, the contamination for tender stems was 25.5 %; disinfected with 70%ethanol for 30 s and with 0.1%HgCl₂ for 10 min, the contamination for old stems was 26.5%; disinfected with 70%ethanol for 30s and with 0.1 %HgCl₂ for 3 min, the contamination for seed embryos was 18.6%; disinfected with 70%ethanol for 30 s and with 0.1 % HgCl₂ for 5 min, the contamination for leaves was 34.3 %.The stems with axial buds could induce the germination of the axial buds,The best medium for it was WPM + 6-BA 0.5 mg/L + NAA 0.05 mg/L, Whose inducement rate reached to 62.9%, and the axial bud germinated only in 3days. Adding 2.0mg/L gibberellins (GA₃) to the culture medium could increased the axial bud sprouts growth length effectively. The tender stems could still be induced to bubs, on the medium of MS + 6-BA 1.0 mg/L + NAA 0.05 mg/L, the inducement rate was 51.9%. To ensure the highest inducement rate, we should sample between April and May. In tissue culture of S. sebiferum Roxb, the phenomenon of turning brown was serious. Adding 500 mg/L PVP to the culture medium and replacing culture medium at the right moment could obviously control it.Callus induced from hypocotyls and leaves was better in the condition of light after darkness. The optimal medium for callus induction from hypocotyls was MS + 6-BA 2.0 mg/L + NAA 0.05 mg/L + 2,4-D 0.05 mg/L,with the inducement rate was 53.6%. The optimal medium for callus induction from leaves was MS + 6-BA2.0 mg/L + NAA 0.05 mg/L + 2,4-D 0.05 mg/L, with the inducement rate was 38.2 %.MS + 6-BA 1.0 mg/L + KT 0.5 mg/L + NAA 0.5 mg/L was the optimal medium for subculture. The rate of inducement was 81.2% and the multiplication coefficient was3.2.Roots were induced on the culture medium with NAA or IBA, and the rooting rate of them was high. The optimal medium was 1/2 MS + NAA 0.5 mg/L. Besides, 2 g/L active carbon was added to the medium and the rooting rate could increase to 97.4%. The roots were good for transplanting. The better basal material was sand: nutrient soil (1:1) and the survival rate would reach to 83.3 %.