| In this experiment the seeds, immature embryos and stem nodes were used as explants for in vitro culture and artificial seeds production in Acacia species such as Acacia crassicarpa, A. melanoxvlon, A. implexa, A. nerifolia, A. lcptocarpa, A. cincinnata, A. aulacocarpa and A. confusa, especially in A. crassicarpa and A. confusa. The main contents of the experiment were as follows: (1)establishment of the system of the high-effeciency regeneration in vitro in A. crassicarpa; (2)induction of callus, cuture of suspensions and isolation of protoplasts in Acacia species such as A.confusai, (3) in vitro propagation of A. melanoxvlon, A. implexa, A. lcptocarpa, A. cincinnata, A. aulacocarpa; (4)production of artificial seeds and RAPD analyses in A. crassicarpa. The main results were described as follows:1 .The effect of different pre-treatments on the germination of the Acacia seeds. The in vitro germination rate reached 95% under the pre-treatment of the thick vitriol for 25 min combined with the boiled water for 20 min on Acacia.crassicarpa. seeds. Under the pre-treatment on the seeds of several imported Acacia spp., they all germinated at high frequency with 80.0%-90.0%.2. Establishment of the system of the high-effeciency regeneration in A. crassicarpa. The experimental results showed that the effects of the natural additives on the proliferation rate was asthe order-banana juice >tomato juice> leaf of A. crassicarpa ; the rapid multiplication, shootgrowth and rooting could be conducted in the same time on the 1/2 MS medium with 0.1 %AC ; and the surival rate was up to 87.5% after transfer into the mixture of sand and the soil from Acacia spp. forest (3:1) .3. The histiocytic observation the green tumour-shaped tissues (GTT) by paraffin section in Acacia crassicarpa. The results indicated that both the adventitious bud formation and somatic embryogeneis existed in the GTT and both originated from the surface cells of callus from the base of shoots, which belonged to exogenesis. The somatic embryogeneis pocessed these stages such the prembryos, gouble embryoids, hearted-shaped embryoids and cotyledon embryoids.4. Induction and long-term subculture of callus in Acacia spp.. The hypocotyl and immature embryos were uesed as explants. The results showed that the combiantion of hormones of 0.5 mg.L-1 2,4-D and 2.0 mg.L-1 BA faliciated to induce callus, and the type of friable light-yelllow callus could be maintained for a long time on the medium with 0.5 mg.L-1 2,4-D, 2.0 mg.L-1 BA and 300 mg.L-1 LH.5. Establishment and long-term maintenance of cell suspensins in A. confusa. The resulted showed that the suspensions cell lines could be be quickly established within 2 weeks from the light-yellow friable vigorous calli; sucrose was the better carbon source for miantenance of suspension cell lines; and the suspensions could be long subcultured alternatively cultured with the solid and liquid media.6. Isolation and purification of protoplasts in A. confusa. High-yield and hgih-viability protoplasts were obtained from the vigorous dispesive suspensions when they were inoculated into the CPW—13M enzymatic mixture containing 1% cellulose and 2% pectinase and kept still in dark for 16 h.7. Development of the technique of the production of A. crassicarpa artificial seeds. 2-3 mm -long shoot cuts were used as encapsulating materials. The results showed that the 2% sodium alginate and 20 min of encapsulating time were the best for the system of calcium alginate beads;...
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