无距虾脊兰营养器官解剖结构及其生态适应性

采用石蜡切片法对无距虾脊兰(Calanthe tsoongiana T.TangetF.T.Wang)营养器官解剖结构进行研究。结果显示,无距虾脊兰叶为等面叶,与一般植物相比,表皮毛和气孔器较少,均分布在下表皮,气孔器稍外凸,叶片维管束分化程度不一,木质部厚度远大于韧皮部。假鳞茎由表皮、基本组织和维管束组成,基本组织发达,含有丰富的内含物。维管束散生于基本组织中;根主要由根被、皮层和中柱组成,根被通常可见4层,皮层由8~10层薄壁细胞组成,菌丝体通过破坏根被细胞侵入皮层。除正对木质部脊的中柱鞘细胞外,其余中柱鞘通道细胞全面增厚,维管束类型为辐射维管束,中柱中央为薄壁细胞组成的髓。无距虾脊兰营养器官的解剖特征表现出阴生植物的特点,引种栽培过程中应注意适当遮荫和通风。

Anatomical structure of the vegetative organs of Calanthe tsoongiana and their ecological adaptation

The anatomical characteristics of the vegetative organs of Calanthe tsoongiana T.Tang et F. T. Wang were studied by paraffin sectioning to explore their ecological adaptation. Results showed that the leaf was isobilateral. Furthermore, compared with general plants, the leaves had less epidermal hair and fewer stomata, which were both distributed in the lower epidermis. The stomatal apparatus was slightly convex. The differentiation degree of the vascular bundles in the leaf was varied, and the xylem was much thicker than the phloem. The pseudobulb consisted of epidermis, ground tissue, and vascular bundles, and the ground tissue was well developed with abundant inclusions. The vascular bundles were scattered throughout the basic tissue. The root was mainly composed of the velamina, cortex, and stele. The velamina consisted of four layers of cells and the cortex was composed of 8–10 layers of parenchymal cells. The mycelium infected the cortex by destroying the velamina cells. The middle columnar channel cells were thickened on all sides, except the pericycle cells facing the xylem ridge. The vascular bundles were of radiative type and the pith, which was located in the center of the stele, consisted of parenchymal cells. Thus, the anatomical structures of the nutritive organs of C. tsoongiana showed features of a shade plant. Shade treatment and well-ventilated conditions should be provided in the processes of introduction and cultivation.