Study On Anatomical Characters And Landscape Application Of Several Species In Michelia L.

Materials of this study were based on the leaves, midvein, leafstalk, periant, bract and pedicel of 24 species of Magnoliaceae, including 21 species & 2 varieties of Michelia L. and Tsoongiodendron odorum. Scanning Electron Microscope and light microscope were used to observe morphology and anatomy characteristics of the materials. Simultaneously, the phylogeny relationship among correlative traits and the significance of ecological adaptation were discussed and the present situations and prospects of application of Michelia L. as Landscape Plants were also analyzed. The main results were as follows:(1)The type and location of stomatal apparatus in leaves, perianth and bract, oil in leaves and perianth, ornament of perianth cells were the same in Michelia L. and Tsoongiodendron odorum. It means that the plants of Michelia L. and Tsoongiodendron odorum belongs to a nature group.(2) The anatomy characteristics of the leaf and perianth of Tsoongiodendron odorum were the same as the plants of Michelia L., so it should be grouped into Sect. Michelia.(3) The plants were observed in Michelia L. The results showed that the plants of the leaves with 3-5 layers hypodermic midvein belonged to Sect.Michelia; the plants with small or unremarkable midvein or leafstalk pith cavity was in Sect. Micheliopsis; while the rate of palisade tissue to spongy tissue was more than 1, the plants belonged to Sect.Dichlamys; the upper epidermis with hypldermic structure of leaves was in Sect.Anisochlamys. From the analysis on the morphology and anatomy characteristics of the Michelia L., the division of subgenus and group of Michelia L. was thought to be reasonable. Liu Yuhu's notion that devised Michelia L. into 4 sections was agreed on.(4) The anatomical characteristics similarity of M.figo and M.skinneriana could reflect the close genetic relationship of them. So did the M.macclurei and M.maudiae. M.balansae var.appressipubescens and M.foveolata var.cinerascenswere varieties of M.balansae and M. foveolata respectively. Close relative relationship of the two groups could be confirmed by their similarities and differences by which the two groups could also be distinguished.(5) Morphological characteristics of bract upper and lower epidermis of Michelia L. and Tsoongiodendron odorum were quite similar to the leaf upper and lower epidermis of them respectively, from which it was suggested the bract would be the transition form between leaf and perianth.(6) There were many idioblasts in the leaves, midvein, leafstalk, periant, bract and pedicel of Michelia L. and Tsoongiodendron odorum, such as oil cell, crystal cell, tannin cell and so on. The existing of idioblasts had a very important reference significance for systematic evolution and ecological adaptation.(7) From morphology and anatomy characteristics of leaves, midvein, leafstalk, periant, bract and pedicel, it was showed that Michelia L. and Tsoongiodendron odorum were typical mesophytes and their characteristics were the manifestation of environmental adaptation. Each species of plant had it particular structure characteristics to adapt environment, but there was difference in ways of expression.(8) Michelia L. was an important tree species in the evergreen broad-leaved forest of China. Their flower, leaf and fruit were all beauty and had high ornamental value. They also had certain resistance and adaptability to bad environment. They played an important role in greening, beautifying the environment and maintaining urban ecology balance, so they were a kind of landscaping plants that had wide development prospect.