Preliminary research report on tissue culture of Acacia auriculaeformis × Acacia mangium.

[Objective]The rapid propagation technique of Acacia auriculaeformis×Acacia mangium was studied to screen proper culture medium formulation for different stages and to achieve industrializing breeding. [Method]Using hybrid Acacia stems as explants for tissue culture, effects of growth regulators including 6-BA, NAA and IBA of different concentrations on induced sprouting, subculture propagation and root induction were explored. [Result]The results showed that in case of 0.2 mg/ L NAA, the initial induction rate was 60.0% when no 6-BA was added, and the induction rate was 42.0% when there was0.2 mg/L 6-BA. At 0- 0.5 mg/L NAA, proliferation coefficient increased with the increase of 6-BA concentration. At 0.8 mg/L 6-BA, the propagation coefficient was 4.2. When 6-BA was above 1.0 mg/L, transgenerational seedling proliferation coefficient was 1.0. Using the improved MS as the basic medium, under the condition of 1.0 mg/L NAA, rooting induction rate was 17.5% and 24.0% for 0.5 and 1.0 mg/L IBA, respectively. Using the 1/2 modified MS as the basic medium, under the condition of 1.0 mg/L NAA, rooting rate was 91.7% and 50% for 0.5 mg/L IBA and 1.0 mg/L IBA, respectively. When rooting seedlings were transplanted in substrate with yellow subsoil and river sand or vermiculite mixture, transplanting survival rate was more than 85.0%. [Conclusion]Improved MS +NAA 0.2 mg/L medium was more appropriate for the initial induction medium. Improved MS+6-BA 0.8 mg/ L+NAA 0.5 mg/L was conducive to the growth of transgenerational seedlings. 1/2 modified MS+NAA 1.0 mg/L+IBA 0.5 mg/L was better for root induction.