大叶榕和细叶榕叶片解剖结构及其适应性

Observation of foliar anatomical structures and adaptabilities of Ficus virens var. sublanceolata(Miq.) Corner and F. microcarpa Linn. F.

对大叶榕(Ficus virens var.sublanceolata(Miq.)Corner)和细叶榕(F.microcarpa Linn.F.)的叶片解剖结构以及电镜下气孔形态特征进行了观察和比较,并对大叶榕和细叶榕叶片对环境的适应性进行了探讨.结果显示,大叶榕叶肉无明显的栅栏组织和海绵组织分化,为等面叶,叶肉细胞排列紧密;上、下表皮由单层细胞构成,角质层极薄,下表皮上的角质膜呈网状凸起;气孔密度大,分布在下表皮并明显突起,在气孔周围没有角质层拱盖.细叶榕为异面叶,海绵组织细胞间隙大;上、下表皮由2层细胞组成复表皮,并具较厚的角质层,下表皮上的角质膜呈波浪状凸起.气孔分布在下表皮并内凹陷,气孔周围有角质层拱盖,拱盖缘厚突起.根据对两种植物叶脉的粗细、表皮的组成、细胞大小,角质层厚度、气孔凸凹程度和密度等方面的分析,表明细叶榕的对旱生环境的适应能力强于大叶榕.

The comparative observation and analysis of anatomical structure and epidermis aspects of leaves of Ficus virens var.sublanceolata（Miq.） Corner and F.microcarpa Linn.F.were demonstrated by light microscope and scanning electron microscopy（SEM）.What＇s more,adaptability to the environment was also inquiried.The results showed that the leaf of F.virens var.sublanceolata（Miq.） Corner was isobilateral leaf,and that mesophyll cells compactly arranged were not differentiated to palisade tissue and sponge tissue.The epidermis was composed by one layer of cells.Corneous layer was very thin and reticular protuberance.Stomatas were only found in lower epidermis and density of them was high.Stomatas were strong protuberance but not protected by outer stomatal rim.The leaf of F.microcarpa Linn.F.was bifacial leaf and mesophyll cells were loosely arranged.The epidermis was composed by 2 layers of cells and the corneous layer was thick but wavy protuberance.Stomatas were only found in lower epidermis and invagination.There were thick and protuberant outer stomatal rims that protect stomatas.According to the analysis of diameter of vien,form of epidermis,the size of cells,corneous layer thickness,stomatal protuberance or invagination and density,F.microcarpa Linn.F.was concluded with higher drought resistance.