霍山石斛组培苗移栽后微观结构与微区元素的变化研究

Changes in Micro-structure and Micro-area Elements of Post-transplantation Plantlets from Dendrobium huoshanense

采用扫描电镜及X射线能谱仪技术,研究霍山石斛组培苗移栽后各器官组织的微观结构和所含元素的变化,以了解霍山石斛组培苗生长发育以及药效成分的状况。结果表明:(1)霍山石斛组培苗移栽2个月后,根增粗近1倍,具有根被,且根被细胞壁的网络状增厚更加明显,表皮、皮层、中柱发育分化更加完善,Mg、Si、Cl、S、K、Ca元素含量提高,其中Ca增长了2.76倍。(2)茎表面纵向凹陷增多,内部结构致密,维管束发育较为完善,细胞内充满物质,Mg、Si、Cl、S、K、Ca、Fe、Cu、Zn元素含量增多,尤其是K和Fe分别增长了3.25倍和4.61倍。(3)叶增厚,具有了角质层,气孔形状更加饱满,叶肉细胞内含物丰富,Mg、Si、Cl、S、K、Ca、Fe、Mn、Zn的含量显著上升,其中K升高了17倍。(4)与根、叶相比,茎中所富集的元素种类最多。研究认为,霍山石斛试管苗移栽后,生长发育趋向完善,各项功能增强,细胞内含物质增多,元素成分丰富并且含量提高,体现出对移栽环境的良好适应性。

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 2months.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.