Studies On Tissue Culture And Raising Contents Of PLBs' Effective Components Of Dendrobium Moniliforme

In this paper, tissue culture of Dendrobium moniliforme and the influence of different factors on the accumulation of effective components in PLBs were studied. The results were as follows:We have got higher germinating rate from the mature seed of Dendrobium moniliforme (L.) Sw. at hormone-free MS medium. It is very easy to differentiate for protocorm from the seed germination. After two months, protocorm developed young seedlings.The explants exerted strong influence on the induction of PLBs. It is very difficult for mature stems to dedifferentiate.The induction rate of young tissues were higher than mature stems, but young stems is easy to brown. The cluster shoots were the suitable explant.TDZ could promote the induction of PLBs, but the major disadvantage of using TDZ include differcult in elongation and rooting of shoots. The PLBs had the best induction rate in the MS medium contained 1 mg/L BA, 0.1 mg/L NAA and 0.1 mg/L TDZ from analysis of orthogonal experiment. When PLBs were transferred to 1/2 MS medium contained 1 mg/L NAA and 30g/L sucrose, the multiplication capacity is better than other medium. Compared with dark condition, light could promote PLBs multiplication. The PLBs differentiation could be promoted by mixing higher concentration BA with lower concentration NAA. BA and NAA had different effects on seedling growth. BA was beneficial for tiller while NAA could promote growth, but high concentration NAA inhibited the seedling growth. The result showed NAA and IBA at lower concentration were suitable for seedling growth.The growth curve of PLBs on liquid stationary medium was "S" type. There was an initial lag phase of ten days followed by a period of exponential growth, PLBs reached the growth peak and declined after fifty days of inoculation. The content of total alkaloids and polysaccharides increased with the increase of PLBs biomass. They reached peak and declined after forty days of culture. These results indicated product formation was growth associated. The contents of, two effective components in PLBs approached or exceeded that in stem of wild Dendrobium moniliforme .The growth curve of PLBs on solid medium was also "S" type. PLBs on solidmedium multiplied faster than those on liquid medium from dry weight increasing. The solid medium was suitable for the accumulation of total alkaloid and the liquid medium suitable for the accumulation of polysaccharides. Light promoted PLBs growth and accumulation of polysaccharides. The content of polysaccharides enhanced with the increasing of light intensity. The dark condition inhibited PLBs growth and accumulation of polysaccharides, but there was a litter increase on the content of total alkaloids. MJ and geraniol all could inhibit the PLBs growth. With the raising of their concentration , their inhibition inhanced. MJ 100mol L-1 could inhance the accumulation of effective components in PLBs, but geraniol at different concentration inhibited the accumulation of effective components in PLBs.