The Anatomical Structural Study On Linnaea Borealis L. In Cold Areas Of Changbai Mountain

By scanning electron microscopy and optical microscopy,combining the use of paraffin sections and the segregation technology of plant stems and wood, through three-dimensional structure and the structure of two-dimensional transmission ratio of the experiment, a systematic study about the anatomical structures of Linnaea borealis L. over more than 2000 meters above sea level in Changbai Mountain alpine were carried on.The results showed that: creeping stem of Linnaea borealis L. was around 2m long, upright stem was about 10cm high, their diameter was about 0.3cm. The results about plant print identification on apparent structural of Linnaea borealis L. showed that: mounted type of radial wall was "I type", the type of sub-ward cells was"row double cells type".The roots of Linnaea borealis L. mainly were adventitious roots, spread to superficial soil, especially in the branch, the primary structure of the root was two proto type, the started differentiation of the primary xylem of root was the foreign-style conducive to water absorption.The epidermis has been replaced by periderm on the surface of stem. Periderm cork cells was nearly square or irregular, large caliber, large quantities, cascading arrangement. The caliber of the outermost layer of cork cells was large, filled the air. These characters were conducive to environment for long-term living in the cold, even in the living environment of forty degrees below zero, a thicker and more full of large air cork cells, can play the role of cold insulation.There was marrow in the central of stem. It was the evolution of the tube in the column in the system development, but is different from other vascular plants forming a layer of intermittent activity. This characteristic severely limits the diameter of the stem of wood not unlimited increase thick wood stem very slender.The leaves can continue to live for two years, and was close to the cuticle. The cuticle of the leaf gives the existence of cold stress. Big leaf intercellular spaces form a larger, more interconnected aerenchyma. This feature was close to the damp environment. Perforation plate type though segregation of wood vessel elements was single perforation. The type of pits of vessel wall was in turn type, it was the evolution of the structure of evolutionary type.This study provided the evolution of Linnaea borealis L. and antagonism in the evolution of structure of cold stress with some references.