Establishment of tissue culture technique system on Cunninghamia lanceolata superior clone

ObjectiveA Cunninghamia lanceolata superior clone rapid propagation technology system was estab-lished to provide technical for large-scale C. lanceolata seedling production.MethodUsing stem tip of stem base or root germination branch of 15-year C. lanceolata in Quanzhou,Guilin as the explants,the optimal HgCl2 soaking sterilization time was selected,and buds were induced and proliferated by adding different hormone combinations to 1/2MS as the ba-sic medium,and different auxins or auxin combinations were added to 1/4MS as the basic medium for rooting culture,in order to screen out the appropriate medium in tissue culture of C. lanceolata.ResultThe induction rate of bud of C. lan-ceolata stem tip was 74.3% and the average length of induced buds was 2.3 cm in culture medium of 1/2MS+0.8 mg/L 6-benzylaminopurine(6-BA)+0.3 mg/L indole butyric acid(IBA). In culture medium 1/2MS+0.6 mg/L 6-BA+0.3 mg/L IBA,the subculture multiplication number of the induced buds was moderate,the bud growth was fast and effective bac-teria number was large. Rooting rate of C. lanceolata subculture seedlings could be up to 90.7% in culture medium of 1/4MS+0.5 mg/L IBA+1.0 mg/L ABT No.6 rooting powder.Conclusion6-BA mass concentration is the main factor that affects induction rate of C. lanceolata explant,and also affects germination number of buds. IBA mainly affects growth speed of the buds. The proper mass concentration of auxin can promote rooting of C. lanceolata tissue culture seedlings, but high mass concentration auxin inhibits the rooting. In actual production,using 1/2MS+0.8 mg/L 6-BA+0.3 mg/L IBA as medium for induction and growth of bud of C. lanceolata stem tip,1/2MS+0.6 mg/L 6-BA+0.3 mg/L IBA as subcul-ture medium for induced bud of C. lanceolata stem tip and 1/4MS+0.5 mg/L IBA+1.0 mg/L ABT No.6 rooting powder as rooting medium for tissue culture seedling of C. lanceolata,large-scale C. lanceolata superior clone seedling production can be realized.