麻黄属6种植物茎叶表皮的扫描电镜观察

SEM observation on leaf epidermis of different Ephedra Species

目的:通过对麻黄属植物茎、叶表面气孔及微形态特征观察,为其遗传育种及分类研究提供重要微观特征和依据。方法:利用扫描电镜观察6种麻黄属植物茎、叶表面气孔密度、气孔长轴、短轴、气孔形态及茎、叶表面特征。结果:6种麻黄属植物之间气孔密度、茎、叶表面特征存在不同程度的差异;气孔表现出典型旱生植物的特征,略下陷,气孔保卫细胞被厚的角质层覆盖,并形成突起状角质唇状物;气孔大小、形状在种之间无明显区别;叶表面、茎表面气孔均属于无规则型,但形状明显不同,前者主要呈长方形或六边形,后者为窄条形或哑铃形。结论:麻黄属植物气孔的类型及特征比较固定和保守,气孔的大小、形状仅在种内有变异,种间差异较小,分种的价值不大,但在植物分类上具有重要的鉴定价值。

Objective： Characters of stem epidermis, leaf epidermis and stoma could be used as important microcosmic morphological characteristic when inheritance trend is studied in Ephedra breeding and identification. Method： The stomatic density, stoma major axis and mimor axis, stomatic morphylogy, characters of leaf and stem epidermis of 6 Ephedra plants＇ stems were examined by SEM. Result ：The stomatic density and characteristic of leaf epidermis and stem epidermis in six Ephedra species was differenc ,there were no obvious morphological differences in stoma shape and size. The guard ceils were covered with heavy cuticle and sunken stomata, which were the typical characteristics of xerophytes. The stomas of leaf lower epidermis were oblong or hexagon, but the stomas of steam epidermis were narrowed-oblong or dumbbell-shape, they all belonged to anomalous type. Conclusion： The stoma type and characters of Ephedra plants is stable and conservative,there was no obvious morphological differences in stoma shape and size between species, so it is difficult to dis.tinguish different species by the variance of stomas, but that can be applyed to distinguish Ephedra from others at plant taxonomy.