Leaf Anatomic Structure of Wikstroemia indica (L.) C.A. Mey.and Its Ecological Significance

The leaf anatomic structure of Wikstroemia indica(L.) C.A.Mey was studied under light microscope by using frozen section technique.The results showed that the leaves of W.indica exhibited morphological characteristics of xerophytism,heliophyte with mesophyte.Leaf epidermis consisted of one layer of closely arranged and irregular cells with thick cuticular membrane on outer cell wall,and there were not hair on abaxial and adaxial epidermis.Stomata are anomocytic type,large and sunken,and only sparsely distributed on abaxial epidermis.The two layers of palisade tissue each distributed under the abaxial and adaxial epidermis,respectively.The upper palisade tissue consisted of 1-2 layer(s) regularly arranged cylindrical cells,and the lower palisade tissue and spongy tissue cells arranged loosely,with a ratio of 1.16:1 for the palisade tissue to the spongy tissue.There were rich chloroplasts in the mesophyll cells.The leaf main vein is well developed with endophytic vasucular bundles and hadrocentric fibers.All these characteristics indicated that the leaf structure of W.indica could well adapt to its growing environment.