Structural Study Of The Plain Five Plant Antagonistic To Salt Stress

Light microscopy was used to investigate the anatomy of 5 species of salt-enduring plants lived in the Songnen Plain. The result showed that Humulus scandens (Lour.) Merr., Chenopodium album L., Incarvillea sinensis Lam., Prunus salicina Lindl. and Forsythia suspense (Thunb.) Vahl. have various halo-tolerant constructions of morphological characters - some are the same, some different from each other.In H. scandens (Lour.) Merr., there exist an abnormal vascular bundle in the center of the pith. The abnormal vascular bundle is morphologically the same as a normal one. There is some big hollow hairs on the surface of its stem, out of which there is a thin-layer cutin. Many multi-cell salt glands were found near the vein on upper and under epidermis. Saliferous vacuoplasts and crystals could be seen in many epidermic cells. Palisade parenchyma takes a larger proportion than spongy tissue in mesophyll.Different from other dicotyls, the cortex in C album L. is composed of mechanical tissue and assimilating tissue, which are alternately arranged with each other. The assimilating tissue is morphologically similar with spongy tissue, and the mechanical tissue become the prominent ridges of the stem. There are some tylosises in vessel elements. In the main vein there exist some abnormal vascular bundles. Salt glands were observed on epidermis. The cutin layer is thin. Big crystals were found in cavities among cells.Leaves of /. sinensis Lam. are isobilateral. The cutin layer is thin. There exist a lot of mucus cells in palisade parenchyma and vein-parallel mesophyll cells. The cells of cortex are loosely arranged, just like aerenchyma. There are many protein-bearing cells in pith. The shape of perimedullary zone is clear.P. salicina Lindl. is different from the other 4 species of plants in test in that the cutin layer out of the stem is thick. Huge crystals were found in cortex cavities. Cortex comes to be aerenchyma. The perimedullary zone could be easily recognized. There is no epidermic hair on the surface. Large cavities also exist under epidermis and occasionally crystals can befound in some of these cavities. There exist many projecting constructions shaped like two guard cells on under epidermis.The stem of F. suspense (Thanh.) Vahl. has hollow pith. The cutin layer on leaves is thin. There are a lot of cup-shaped poly-cell salt glands in depressed sites of both up- and under- epidermis. The spongy tissue take a larger scale in mesophyll than palisade parenchyma, and contain abundant chloroplasts.From the result above, we can draw a conclusion as follow: different plants adapt to one kind of environment with different structures, while varies of the structures carry out similar function. The result of this research can provide significant reference for selecting halophyte and fundamental studying.