Studies On Tissue Culture Of Dendrobium Officinale And Accumulation Changes Of Its Secondary Metabolites

An effective method for rapid propagation of Dendrobium officinale was established toinduct cluster shoots after a series of culture study. took young tissue of aseptic seedling wereexplants, through Stem axillary bud induction pathway and Young tissue intended protocorminduction pathway, two more complete tissue culture regeneration system were established. Apreliminary study for the proposed protocorm in a different light, different training methods anddifferent natural additives medium conditions secondary metabolites content were couducted.1.Tissue culture and rapid propagation of Dendrobium officinale(1).Buds waysDendrobium officinale plantlet grew best in MS medium. The proliferation rate of clustershoots reached the highest in MS medium with NAA0.1mg/L and6-BA2.0mg/L．30dproliferation coefficient is2.82,60d proliferation coefficient is4.8.(2).PLBs waysRespectively to Dendrobium officinale tender stem segments, leaf, stem tip and buds asexplants of PLBs induced, the results showed, the stem segments and bud induction rate wasbest.The stems as explants, the best PLBs induction culture medium for MS+6-BA0.5mg/L+NAA1.0mg/L+2,4-D2.0mg/L, with buds as explants, PLBs optimal induction medium wasMS+6-BA1.0mg/L+NAA1mg/L+2,4-D2.0mg/L. The best medium for proliferation of PLBsMS+NAA0.1mg/L, PLBs differentiation optimum medium for MS+NAA0.1mg/L+6-BA1.0mg/L.(3). Rooting and transplantationThe most suitable medium for strengthening plantlet and taking roots was MS+0.5mg/LIBA+0.5mg/LNAA.The plantlet rooted rapidly and got more roots with0.5mg/L NAA alonein addition. The banana juice could promote growth of plantlet roots．The highest survival ratewere raised, when Seedlings were transplanted into the matrix of pure bark.2. Studies on Induction of Protocorm-like Bodies and Accumulation of Production ofSecondary Metabolites of Dendrobium officinaleThe Protocorm-like bodies were inducted with the young stem section of Dendrobiumofficinale as explant using the method of orthogonal test of three factors at three different levels.The relationship of growth rhythm and its secondary metabolites (total alkaloid content and polysaccharide) accumulation were researched. The results showed that the best inducedmedium was MS+6-BA0.5mg/L+NAA1.0mg/L+2,4-D2.0mg/L.Simultaneously the growth ofProtocorm-like bodies appeard in "S" curve in one semester (60d),reached the growth peak at the40d around. At that time, the total alkaloid content and polysaccharide also reached the peakvalue. The results also showed that the correlation coefficients between the total alkaloid contentand polysaccharide and the growth of Protocorm-like bodies were highly significant. When theleaf were divided from Protocorm-like bodies,the Secondary metabolism production ofProtocorm-like bodies were highest in differentiation phase, and then declined slightly in periodof young seedling.Fresh weight of the proliferation rate of PLBs were significant lower exposed in lightconditions than in dark conditions. The accumulation of Secondary metabolites of Dendrobiumofficinale candidum PLBs were inhibited in various degree.Simultaneously the growth of Protocorm-like bodies appeard in "S" curve in dark conditions.Fresh weight of the proliferation rate of PLBs were significant lower exposed in Solid culturethan in Liquid culture. Polysaccharide content and alkaloid content were much higer in Liquidculture.The accumulationof PLBs secondary metabolite were influencede by different naturaladditives. PLBs fresh weight of the proliferation rate got largest by Potato medium, alkaloid ofPLBs got highest by Banana juice medium. polysaccharide content got largest by apple juicemedium.