| Three types of initial explants from Tilia miqucliana, including stem of seedlings, leaf and root of axenic plantlet, were used to study the organogenesis in this thesis. Different factors were tested for their effects on direct organogenesis and callus inducement. The main results showed that:1. Stem of seedling was the optimal explant for direct organogenesis, and the most suitable medium for inducing adventitious bud was MS+BA 1.0mg·L-1+NAA 0.1mg·L-1+sugar 30g·L-1+agar 5.2g·L-1, on which the most adventitious buds could be induced in 40-day cultivation which were propitious to the continuous generation. The most suitable medium for plant proliferation was MS+BA 0.5-1.0mg·L-1+NAA 0.05mg·L-1+sugar 30g·L-1+agar 5.2g·L-1, on which the multiplication coefficient of adventitious buds could be enlarged more than 4 times. Meanwhile, to appropriately lower the contents of multitude elements (1/2MS) and prolong the culture periods (40d) could be beneficial for the elongation of the adventitious bud. The best rooting medium was 1/2MS + BA 0.1mg·L-1 + IBA 0.5mg·L-1 + sugar 20g·L-1+agar 5.2g·L-1+AC 5g·L-1, on which the adventitious bud could grow out high-quality roots in 40-60 days with the highest rooting rate of 56.6%. When the root length developed to 6-8cm, the plantlet could be transplanted to humus after 5 days acclimation, the survive rate of the regeneration plant was above 80%.2. It was easy for Tilia miqucliana to induce good quality of callus from leaves. The most suitable medium was MS+BA 0.1mg·L-1+2,4-D 0.5-1.0mg·L-1+sugar 30g·L-1+ agar 5.2g·L-1, on which well-grown callus could be induced in great number in 40-50 days. To keep the hearty vigor and differentiation ability of callus, 2,4-D was gradually replaced by NAA, and 0.5-1.0mg·L-1 NAA was most suitable for multiplication of callus with higher multiplication coefficient and healthy growth. Moreover, the addition of Vc(5mg·L-1) could effectively prevent the callus from browning in dark cultivation, but little effect could be found on light cultivation. The full process of inducing adventitious buds from callus had not been studied because of the limited time, on which further research should be done in the future.
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