大花蕙兰幼苗叶片诱导类原球茎

以大花蕙兰无菌幼苗叶片为外植体,成功诱导类原球茎(PLB).叶片部位是影响诱导的关键,只有叶片基部片段能成功诱导出PLB.不同激素配比以及外植体来源对PLB诱导有重要的影响.低浓度的2,4-D和较高浓度的6-BA对于拟球茎诱导PLB具有显著的促进作用.当2,4-D浓度高于0.6 mg/L时,PLB诱导受到显著抑制.较高的2,4-D水平可能有利于PLB诱导初始阶段,但不利于PLB诱导中后期的进一步发育.不同基因型有不同的最佳激素组合.添加0.2 mg/L的NAA对大花蕙兰PLB诱导没有显著影响,但在有的基因型中对PLB诱导有促进作用.以叶片基部片段诱导大花蕙兰PLB是可行的,为转基因研究提供了再生技术基础.

Protocorm-like Body Induced from Leaf-segments of Vitro-seedlings of Cymbidium hybridum

In this paper PLB (Protocorm-like body) is successfully induced from the leaf-segments of vitro-seed- lings of Cymbidium hybridum. PLB could be easily induced only using the base of leaf as explant in this research. The effects of 2,4-D, 6-BA, and NAA on the PLB formation were investigated in different level concentration. The results show that the effects of 2,4-D and 6-BA on the frequency of PLB formation of C. hybridum differ extremely signif icantly. 2,4-D on lower level is an important stimulation to induce PLB, but the inducing of PLB will be restrained when the concentration of 2,4-D is higher above 0.6 mg/L. 2,4-D on higher level is likely to facilitate the inducement of PLB, but make harmfulness against the development of PLB. The frequency of PLB formation increases basically with the increase of concentrations of 6-BA. The frequency of PLB formation is also signifi cantly related to the genotype of explants. NAA at level of 0.2 mg/L is not an important factor, but is avail- able on the formation of PLB to some special genotype. Obviously it is feasible strategy to induce PLB by leaf- disc of Cymbidium hybridum, which would be more helpful for transgenic research.