大花蕙兰类原球茎形态发生的组织学研究

Anatomy Study on Protocorm-like Bodies Formation and Development of Cymbidium hybridium

以大花蕙兰类原球茎发生发育不同阶段的培养物为试材,采用石蜡切片法对其进行组织学研究。结果表明,类原球茎形成过程中,表层薄壁细胞首先经脱分化恢复分生能力,形成愈伤组织,随后在其表面形成瘤状突起——类原球茎;类原球茎继续发育,在其周围形成多个不规则突起,并进一步发育形成新的类原球茎;而原来的类原球茎开始进入器官分化阶段,逐渐形成完整的小植株。根据观察,类原球茎起源可能存在两条途径:体细胞胚胎发生和器官发生。

Anatomy study on the protocorm-like bodies formation and development of Cymbidium hybridium was conducted. The results showed that callus formed firstly from shoot tip of explant, then differentiated into protocorm-like bodies. In the process of protocorm-like bodies proliferation, variegated forms of pre-protocorms formed around one protocorm-like body which developed into a plantlet at the same time. As for the controversial question of protocorm-like bodies derivation, our results showed that the origin of protocorm-like bodies was a specific regeneration process that have both characteristics of the pathways of somatic embryogenesis and organogenesis; the exact regeneration pathway differed according to genotypes and culture conditions.