Study On The Rapid Propagation And Secondary Metabolites Of Dendrobium Officinale Kimura Et Migo.

The effects of basic media, installing methods, types of the explant, culturing conditions, phytohormones etc. on the induction of the protocorm and subculture were studied. The influences of the contents of media and culturing conditions on the contents of metabolites contained in the calli were investigated. The results are as follows:1. Among the 8 media tested, N₆ medium was suitable for the induction of the protocorm like bodies from the immature shoots, and B₅ medium was suitable for the subsequent subculture.2. The induction rate of the protocorm like bodies by 2,4-D, NAA, and IBA respectively was over 65%, and 0.5mg/L 2,4-D, 0.5-1.0 mg/L NAA, and 1.0mg/L IBA was optimal induction concentration. Combinations of 2,4-D and 6-BA or KT were unfavorable to the induction of the protocorm like bodies. The protocorm like bodies induced by 1.0 mg/L NAA+0.3-0.5mg/L6-BA, or by1.0mg/L IBA+0.5 mg/L6-BA growed quickly with glossy appearance, was good for subculture. When NAA was used alone, 0.5 mg/L NAA is optimal for the differentiation of calli. When NAA was used with cytokinine, 0.5mg/L NAA+0.5mg/L6-BA was suitable combination. The amount of the growth induced by 0.5mg/L NAA+0.5mg/L6-BA was bigger than that induced by NAA, or 6-BA respectively. However, high concentration of NAA, or 6-BA was inhibitory to the differentiation and growth of the protocorm like bodies. When IBA was used alone, 1.0 mg/L IBA is optimal for the tube seedling growing and rooting. When NAA was used with IBA, 0.3mg/L NAA+1.0mg/L6-BA was suitable combination.3. The optimal pH value is 5.8 for the protocorm like bodies and subculture. 12 hour light and 12 hour dark cycles were benefit to the differentiation of calli,...