Study On Comparative Anatomy Of Two Different Species Of Euonymus L.

Euonymus alatus(Thunb.) Sieb and Euonymus bungeanus are perennial deciduous shrub or arbor of Euonymus L.in Celastraceae,which are distributed mainly in the north area of China,but also in Korea and far eastern region.Some researches has been done primarily on the chemical composition and pharmacology activity of Euonymus alatus(Thunb.)Sieb and Euonymus bungeanus。This paper is concentrated on the structures and differences of vegetative and reproductive organs of them by using the method of paraffin section,the leaf epidermis loading slice and wood section。With the characteristic study of biology,it provides a new data for taxonomy position of Euonymus alatus(Thunb.)Sieb and Euonymus bungeanus form the point of conformation anatomy and,at the mean time,it gives a elementary study of the relationship between structures and environment and also the study of recommend domestiction。The results are as follows:1.The primary root structures of Euonymus alatus(Thunb.) Sieb and Euonymus bungeanus:Their Casparian strip is not clear in the cortex.And they have Actinostele.The primary xylem is exarch.The primary phloem locates between primary xylems like an island. The pith is shaped in the middle.And the adventitious roots of them are diarch.2.The primary stem structures of them:Archaeopteris,primary xylem is endarch.They have strong pith,and sometimes it becomes into pith cavity when it breaks.Euonymus bungeanus and Euonymus alatus(Thunb.) Sieb have different ratios of timber (xylem and pith) and tegument(phloem and cortex) of annual stem.The former's ratio(2:1) is far bigger than that of the latter(1.2:1),which reflects its strong growth.The primary stem of Euonymus alatus(Thunb.)Sieb is prismatic and it has woodiness wings composed by woodiness cell。3.Although the secondary structures of root and stem are similar between Euonymus alatus (Thunb.)Sieb and Euonymus bungeanus,there are some differences.The former belongs to diffuse-porus wood,and the latter belongs to half-annular-porus wood.Both of them are composed by pitted vessel,that their solitary pores,radial multiple pores and pore-chains.The end wall of vessel is sloped and has simple perforation.Euonymus alatus(Thunb.) Sieb has a little wood parenchyma in the secondary xlem.The paratracheal one is paratracheal parenchyma and the apotracheal one is apotracheal parenchyma.And their wood rays are heterogeneous I. They only have one ray.The periderm comes from cortex parenchyma cells.The phellogen is distributed in strip and the bark comes into being vertical ditch deeply.The average diameters of vessel in their roots are bigger than that of stems,and there have more number of unit area of vessels in stem than that in root.4.The leaf of Euonymus alatus(Thunb.) Sieb and Euonymus bungeanus are dorsi-ventral type.And the cuticle is thicker.The stomata belong to paracytic type,and they are mainly distributed near the vein of the lower epidermis.The stomata numbers of Euonymus alatus (Thunb.) Sieb is 292/mm~2,and the stomata number of Euonymus bungeanus is 584/mm~2. Furthermore,the ratios of palisade tissue and spongy tissue between them are 1.2:1 and 1.5:1. Both of their leafstalks are single-leaf-trace and single-leaf-gap。5.Both of the Euonymus alatus(Thunb.) Sieb and Euonymus bungeanus are bisexual flowers.The calyces is small,and their shapes are labiate.Corolla is sejunct,its hape is crisscross.There are nectarines inside the bottom,which shows that they are entomophilous flower with cross-pollination.Both of them are solid type.The wet stigma is head-like and they have mastoid。The ovaries are concrescence in the bottom.And the pistil is syncarpous.The placentation is axile type and there are 4 chambers in the inferior ovary.There are anatropous ovules in the chambers.The embryo-sac belong to the polygonum type.6.Both of their fruits are capsules.The seed of Euonymus bungeanus's is bigger than that of Euonymus alatus(Thunb.) Sieb's.Their seed belong to the Dicotyledon albuminous seed, atropous embryo;the seed capsules are much thicker.7.There are many crystalloids cluster in each part of Euonymus alatus(Thunb.) Sieb and Euonymus bungeanus's structure,which strength the possibilities of bearing drought,cold,pests, and play a sustaining role in the structure.8.It can be shown from the anatomical structures of Euonymus alatus(Thunb.) Sieb and Euonymus bungeanus that,they are mesophyte,and they all can resist drought,cold,pests and negative press strongly.The structures also indicate that both of them have difficulties in seed reproducing.However,compared with Euonymus bungeanus,it is easier for Euonymus alatus (Thunb.) Sieb to domesticate and reproduce by means of separating plant and cottage.