Study On Comparative Anatomical Structure Of Stems And Leaves Of Four Species Of Syringa L.

Syringa L. belongs to Oleaceae.There are 27 species in Syringa L, which are distributed mainly in the East asia and European.There are 22 species in China,including 18 especial species.There are 20 species in the northeast,including 8 varied species.Recently, the research on the Syringa L is more depthly, related to its chemical composition, pharmacological effects, landscaping, anatomy, introduction and domestication of the research carried out a lot of work,promoting the level of springing operation in the city of Jilin province to take a great significance.This thesis is concentrated on the four species of Syringa L..(Syringa reticulata,S.oblata,S.microphylla,S.villosa), which generally distribute in Jilin province, by using the methods of paraffin section, the leaf epidermis loading slice,wood section and electron microscope scanning to take a research on anatomical structure and take a comparison at the same moment. With the characteristic study of biology, it provides a new data for taxonomy position of four species of Syringa L.from the point of morphology anatomy and, at the mean time, it gives a elementary study of the relationship between structures and habitat and also the study of recommend domestiction。The results are as follows:1.The secondary stem of S.microphylla belongs to annular-porus wood. The secondary stem of S.oblata, Syringa reticulata, S.villosa belongs to diffuse-porus wood.They have strong pith.The secondary stem of structure consists of wood parenchyma cells, wood rays, wood fiber, composed of periderm.2.The four species of Syringa L are composed by pitted vessel. S.microphylla, S.oblata, and S.villosa have simple perforation plate, S. reticulata has multiple perforation.They have a lot of xylem parenchyma, parenchyma for the loop from the tube less, xylem is undeveloped.And their xllem rays are heterogeneousⅡ. The wood rays of Syinga microphylla per square millimeter is 29-59, The wood rays of S. reticulata per square millimeter is35-61,The wood rays of S.oblata per square millimeter is32-53,The wood rays of S.villosa per square millimeter is25～49.3.The leaves of four species of Syringa L.are dorsi-ventral type, The upper and lower layer of epidermis cells of leaves which are arranged in close, pores are only found in the lower epidermis.The stomata belong to ruleless type, they only have guard cells, no subsidiary cells. The upper and lower epidermal cells of Syinga microphylla is polygonal, the upper epidermis is larger, lower epidermis is smaller, the cuticle thickness of 1.19μm,the stomatal index is 0.179, longitudinal section of epidermal cells is under the outward protrusions,the stomata is smaller,and, they are distributed more frequent. The upper and lower epidermal cells of S.reticulata is polygonal, the stomata is smaller, the cuticle thickness of 2.32μm,the stomatal index is 0.223. The stomata of S.oblata is smaller, the cuticle thickness of 1.87μm,the stomatal index is 0.237. The upper and lower epidermal cells of S.villosa is polygonal, the stomata is smaller,and they are distributed more frequent, the cuticle thickness of 3.68μm,the stomatal index is 0.196.4.1t can be shown from the anatomical structures of the stem and leaves of four species of Syringa L,which they are mesophte,all of them are qualified with the characteristic of drought,cold;they are different in seed reproducing.