| Acacia melanoxylon is evergreen arbor, which belong to Mimosaceae originated from the south of Australia, it was one of the most high-arbor in Acacia Species. Ten fine clones of Acacia melanoxylon were investigated in this experiment, the differences among different clones in the processes of tissue culture were studied by using in vitro plant regeneration via organogenesis and indirect organogenesis, which in the improvement of the technology of tissue culture of Acacia melanoxylon and provided a technique support and scientific basis in promoting the industrialization of tissue culture and the wide extension in landscaping. The main results were as follows:1. Establishment of aseptic system of Acacia melanoxylon. The effect of three disinfection methods on the contamination rate of semilignification stem segments in different clones by using random block design. The results showed that the contamination rate of explants in FM1,FM2,FM5,FM6,FM9,FM18,FM19,FM21 under the method of 75% ethanol+2%sodium hypochlorite(8min)+0.1% mercuric chloride(8min) was low, and the contamination of FM3,FM12 by using 75% ethanol+0.1% mercuric chloride(8min) was low.2. Axillary bud induction of Acacia melanoxylon in different clones. An orthogonal test design was applied to analysis the influence of different culture medium on the axillary bud induction among different clones of Acacia melanoxylon, the result showed that different culture medium had significant differences influence on axillary bud induction of the same clone, and as to the same culture medium, the axillary bud induction also were significantly influenced by it. Overall analysis the factors that influencing the axillary bud induction rate, the type of culture medium had most great influence on it, follows was 6-BA, NAA had the least influence on the induction rate.The axillary bud induction rate among different clones vary significantly, the axillary bud induction rate of different clones in sequence from high to low was as follows: FM12>FM6>FM2>FM19>FM3>FM9>FM21>FM1>FM5>FM18. The best culture medium for axillary bud inducing of different clones were selected, among these, the clones of FM1, FM6, FM19 had the same culture medium, namely modified MS+6-BA2.0 mg/L+ NAA0.3 mg/L, and the clones of FM2, FM5, FM12 also had the same culture medium: MS+6-BA2.0mg/L+ NAA0.3 mg/L, follows were the clones of FM9, FM18, FM21 their culture medium were MS+6-BA2.5mg/L+ NAA0.4mg/L, at last the culture medium of FM3 clone was MS+6-BA2.0mg/L+ NAA0.4mg/L.3. Propagation of Acacia melanoxylon with different clones. The effect of different phyto-hormones on propagation coefficient was investigated by using orthogonal test design, the result indicated that different culture medium had significant differences influence on propagation coefficient of the same clone, and as to the same culture medium, the propagation coefficient were also significantly influenced by it. Overall analysis the factors that influencing the propagation coefficient, 6-BA taking the lead, followed was NAA, GA had the least influence on the results. The propagation rate of different clones in sequence from high to low was FM6>FM1>FM19>FM5>FM9>FM21>FM2>FM3>FM12>FM18. The best culture medium for adventitious bud propagation of different clones were selected, among these, the culture medium for the clones of FM1 and FM3 were MS+6-BA0.3mg/L+NAA0.2 mg/L+GA0.3mg/L, and the culture medium for the clones of FM2 and FM6 were MS+6-BA0.3mg/L+NAA0.2 mg/L+GA0.1mg/L, follows was the culture medium for the clones of FM5 and FM21 were MS+6-BA0.3mg/L+NAA0.1 mg/L+GA0.3mg/L, the clones of FM12 and FM19 also had the same culture medium were MS+6-BA0.5mg/L+NAA0.2 mg/L+GA0.2mg/L, and the optimum culture medium for FM9 was MS+6-BA0.3mg/L+NAA0.05 mg/L+GA0.2mg/L, at last the optimum subculture medium for FM18 was MS+6-BA0.3mg/L+NAA0.1 mg/L+GA0.1mg/L.4. Effect of successive transfer times on the propagation of different clones of Acacia melanoxylon. By using random block design, as the increasing of subculture times each clone appeared the relative same principles, their propagation rate showed the tendency of increasing first and then decreasing. Among these the propagation rate of FM1, FM3, FM6, FM9, FM21 reached the highest value at the fourth transfer time, whereas, the propagation rate of FM2, FM5, FM19 reach top value at the fifth transfer time, FM12 and FM18 reached their highest propagation rate at the third time.5. Inducing roots of different clones of Acacia melanoxylon. The effect of different phyto-hormones on rooting rate was investigated by using orthogonal test design. The result showed that different culture medium had significant differences influence on rooting rate of the same clone, and as to the same culture medium, the rooting rate were also significantly influenced by it. Overall analysis the factors that influencing the rooting rate, the auxin of IBA and ABT had the most significant effects and the effect of NAA was small.The whole average rooting rates among different clones in sequence from high to low was FM2>FM5>FM6>FM3>FM1>FM21>FM18>FM19>FM12>FM9. The optimum culture medium for rooting of each clone were selected. FM1 and FM21 had the same culture medium: 1/2MS+IBA0.5mg/L+ABT 1.0mg/L +NAA0.4mg/L, FM2 and FM3 also had the same culture medium: 1/2MS+ IBA 0.5mg/L+ ABT 1.5mg/L+NAA0.4mg/L, the culture medium for clones of FM9 and FM12 were 1/2MS+IBA0.5mg/L+ ABT0.5mg/L+NAA0.4mg/L, followed was the culture medium for rooting of FM5: 1/2MS+IBA0.7mg/L+ABT1.5mg/L +NAA0.4mg/L, and the culture medium for rooting of FM6 was 1/2MS+IBA0.7mg/L+ABT1.5mg/L+ NAA0.2mg/L, at last the optimum culture medium for rooting of FM19 was 1/2MS+IBA 0.5mg/L+ABT1.5mg/L.6. Effect of two-step rooting method on the rooting rate of FM1 and FM6. The rooting rates of FM1 and FM6 obtained the best results at the conditions of IBA concentration 2mg/L and under dark culture for 5d, which showed excellent rooting results, the roots were big and long, their rooting rates were 100% and 97.5% , respectively.7. The survival rate of different clones of Acacia melanoxylon. The survival rate of cultivated substratum in yellow heart soil:peat soil=2:1 was higher than that in yellow heart soil:vermiculite=2:1, and the former growth status of seedling was better than the later. The survival rates of different clones varied significantly, among these the clone of FM5 had the highest survival rate which reached 99%, and the survival rate of FM18 was 57%, which was lowest. The survival rate of ten clones in sequence from high to low was: FM5> FM21>FM1>FM3>FM6>FM2>FM19>FM9>FM12>FM18.8. Sterilization method for different explants of Acacia melanoxylon. The optimum sterilization method for tender stem segments was: 75% ethanol(20s) + 0.1% mercuric chloride(7min), The optimum sterilization method for nodes with axillary buds was: 75% ethanol(10s) + 0.1% mercuric chloride(3min), The optimum sterilization method for young leaves was: 75% ethanol(10s) + 0.1% mercuric chloride(4min).9. callus induction for different clones of Acacia melanoxylon. The effects of different hormones influencing the induction rate of different clones with three different explants was investigated by using orthogonal test design. The result indicated that for the same clone with different explants, the types of culture medium had different influence on the results, and as to the same culture medium, the callus induction rate of different explants were also significantly influenced by it, and the same culture also had significant influence on the callus induction rate . The callus induction rate of nodes with axillary buds had the most favorable result, followed was young leaves, and the callus induction rate of tender stem segments was low. The overall analyzed showed that sequence of factors was 2,4-D>6-BA>NAA.The induction rate of nodes with axillary buds achieved the best result, followed was young leaves, and the tender stem segments showed the induction rate. Therefore, nodes with axillary buds and young leaves was suitable explants materials for callus induction, and tender stem segments was not suitable for this. The callus induction conditions had great differences among different clones. All of the clones of FM1, FM2, FM3, FM6, FM9, FM12, FM18, FM19 can induced with callus, but FM5 and FM21 did not had callus formation. 10. Callus subculture for different clones of Acacia melanoxylon. Five culture medium was designed, the result showed that the combination of 2,4-D and 6-BA was most suitable for the callus subculture of Acacia melanoxylon .The most suitable culture medium for callus subculture of FM1, FM2, FM3, FM9, FM19 were the same, namely, MS+2,4-D(0.5mg/L)+6-BA(2.0 mg/L), the clones of FM6 and FM12 had the best growth performance in the culture medium of MS+2,4-D(0.2mg/L)+6-BA(1.0 mg/L), and the callus of FM18 didn't grow in all above culture medium, and finally browned and died.11. Effect of anti-browning agents on browning of callus. The clones of FM6 was taken as the materials for callus induction, the results showed that vitamin C showed the best effects of inhibited the browning of callus when its concentration was 100mg/L, the browning rate was 29.3%.12. The differentiated of callus of Acacia melanoxylon in different clones. An orthogonal test design was applied to analysis the influence of different ratio of hormones on the callus differentiated among different clones. The results showed that different culture mediums had significant differences influence on callus differentiated of the same clone, and as to the same culture medium, the callus differentiated of different clones were also significantly influenced by it. The overall analyzed showed that both 6-BA and NAA had significant influence on the rate of callus differentiated, and the effects of 6-BA was bigger than that of NAA, they both show the great callus differentiated rate with low concentrations. The whole sequence of callus differentiated rate among different clones was FM1>FM19>FM9>FM2>FM12.The most suitable culture medium for callus differentiated of FM1, FM9, FM12, FM19 were the same, namely, MS+6-BA0.5mg/L+NAA0.2mg/L, FM2 had the best differentiated performance in the culture medium of MS+6-BA1.0mg/L+NAA0.2 mg/L. the clone of FM3 and FM6 didn't differentiated with callus.
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