Abstract:Dendrobium huoshanense tissue culture seedlings were transplanted to field environment.In order to get better understanding of the development and officinal components in the plantlets,we investigated the changes in micro-structure of roots,stems and leaves by SEM after 2 months.The elements in these organs were analyzed by means of Energy Dispersive Spectrometer.(1)After comparing with tissue culture seedlings,we found robust post-transplantation plantlets with nearly doubled roughness of roots,the obvious velamina and root cells with significant cellulose network thickening of the velamina cell wall.The structure of epidermis,cortex,and stele developed more perfectly,meanwhile the contents of Mg,Si,Cl,S,K and Ca in roots markedly raised,among which Ca grew 2.76 times.(2)Healthy stems were characterized by several features such as conspicuous surface longitudinal depressions,compact anatomical structure,obviously scattered vascular bundles,and full stem cells with abundant inclusions.The contents of Mg,Si,Cl,S,K,Ca,Fe,Cu and Zn increased significantly,with a 3.25 times increase in K and a 4.61 times increase in Fe.(3)Leaves were found with conspicuous thickening,full stomata,and richer inclusions in mesophyll cells.A significant increase of element contents in leaves was found for Mg,Si,Cl,S,K,Ca,Fe,Mn and Zn,with a 17 times increase in K.(4)More elements were accumulated in stems than in roots and leaves before or after transplanting.In summary,plants grew more perfectly and each function enhanced.Cell content got much richer.More elements in plants and the contents of most elements increased.Those indicated good adaptability of D.huoshanense tissue culture seedlings for the transplanting environment.