摘要
对 7种常绿阔叶植物叶片的解剖学特征的观察结果表明 ,它们的叶片在结构上均表现出典型的旱生特点 :异面叶 ,上表皮细胞较厚且排列紧密 ,具发达的角质膜 ,无气孔器分布 ,下表皮细胞较小 ,气孔器密度较大 ;栅栏组织细胞层数较多 ,排列紧密 ,海绵组织细胞排列极其疏松 ,并形成通气组织 ;中脉及其输导组织和机械组织发达。越冬叶和越夏叶在解剖结构上存在一定的差异 :前者在角质膜 ,叶片厚度和栅栏组织厚度等方面比后者厚 ,而在气孔密度和输导组织方面则比后者略有减少或不发达。这些差异 (发育可塑性 )是常绿阔叶植物适应冬、夏季截然不同的两种生境 (生境的时间异质性 )
Ecological anatomy of leaves in 7 broad-leaved evergreen plants is studied in this paper. The results show that all plants share typical xerophytic features as follows: the leaf blades are all typical back-abdomen bifacial type,compared to the lower epidermis which formed by one layers of small cells. The upper epidermis were formed by one or two layers of bigger cells on which covered with thicker cuticle. There are many stomas distributed in lower epidermis,while the upper epidermis have not any stomas. The palisade tissue consists of many layers of cells that line up densely,and cells of the spongy tissue line up loosely and formed aerenchyma. Middle vein was comparatively developed with obvious mechanical tissues and transport tissue. There are some differences in the structure of winter and summer leaf blades in broad-leaved evergreen plants:the thickness of cuticle,palisade tissue and leaf blade of the winter leaves are all thicker than that of the summer leaves,while the density of stomas and transport tissue of the former are less or less developed than that of the latter. These differences in the structure of winter leaves and summer leaves (developmental plasticity) reflect the adaptation of broad-leaved evergreen plants to the two different completely habitats in winter and summer(time heterogeneity of habitat).
出处
《广西植物》
CAS
CSCD
北大核心
2004年第4期334-338,F005,共6页
Guihaia
