利用扫描电镜和透射电镜观察了琼花叶片表皮形态和叶绿体发育结构特征.结果显示:(1)叶上表皮毛分布稀疏,多为单毛和分枝少的复毛,下表皮分布较密,多为星状复毛,在叶脉表面及周围分布最为密集.(2)叶芽细胞中有较多前质体发育成叶绿体,叶绿体通过出芽和分裂实现增殖.成熟叶片叶绿体形态以球形为主,近细胞膜分布,老叶片叶绿体基粒片层结构稍模糊,但叶绿体形态和分布变化不大.对叶片表皮毛作为植物分类学依据以及琼花叶绿体的发育过程进行了讨论.%Morphological characteristics of the leaf epidermis, epidermal hairs and chloroplast development were investigated by scanning and transmission electron microscopy. Epidermal hairs, ranging from a simple hair to multi-branched hairs, are distributed sparsely on the adaxial epidermis of leaves, whereas stellate hairs are distributed densely on the abaxial epidermis of leaves, especially on the leaf veins. In the cells of leaf buds, many proplastids develop into chloroplasts and during the proliferative stage chloroplasts replicate by budding and division. In the cells of mature leaves, chloroplasts are mainly plump or spherical in shape and distributed along the cell membrane. In the cells of senescing leaves, the chloroplast lamellar structures are degenerated but the chloroplast form and distribution change little because photosynthetic functions are retained up until leaf abscission. The epidermal hairs as a morphological character in plant taxonomy and the process of chloroplast development are discussed.
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