摘 要 ：黑节草（Dendrobium candidum Wall ex Lind．）2—6个月种龄的胚均处于球形胚阶段，不同种龄的胚在体积大小、胚细胞数目、胚细胞内的淀粉粒含量和超微结构上有差异。在离体培养条件下黑节草种子萌发率可达95％，种子萌发后形成原球茎，原球茎可以直接发育形成幼苗，又可以由原球茎产生大量愈伤组织，由愈伤组织再分化发育成幼苗。种子萌发过程中，胚顶端分生组织细胞的淀粉逐渐消耗，淀粉的变化与分生组织和子叶的形成有明显的相关性。
Abstract:The embryo of Dendrobium candidum Wall ex Lindl. in different stages is globular. But embryos are different in shape,cell numbers,starch grains germination rate is 95% in vitro. Protocorms are dormed from embryo. The protocorm can directly form seedling or callus. The callus may differentiate into seedling again. During seed germination the starch is reduced gradually in the cells at the top of the embryo. The reduction of starch may be closely related to the meristem and the formation of the cotyledon.