Study On Physiological Ecology And Rescue Technique Of Distylium Chinense (Fr.) Diels

Distylium chinense(Fr.)Diels is a kind of evergreen shrub,belong to Hamamelidaceae,which mainly distribute on the craggedness cliffes and hillsides under 150m of water-level-fluctuating zone along two sides of the Yangtse Three Gorges.Shape of the tree is unique,with thick base stem,short trunk and curving branches.Causing the advantage mentioned above,D.chinense is an ideal material for cultivated miniascape.Root system of D.chinense is very developed with abundant branch root and hard root as iron, all the which endow this kind of plant with great resistance to submergence,flood and soil-burring.It is an ideal kind of tree to plant in the Yangtse Three Gorges.After the accomplishment of Three Gorges program, the original habitats was submerged,the plant population of the original habitats disappeared subsequently, which has created an urgent need to rescue D.chinense.Based on carefully investigating D.chinense's 8 populations size,distribution and living condition on bank of Youshui river and Wu gorge,research it's orphological diversities,bourgeon character,yong plant's fastness and so on;at the same time,study on the rescues technique to look forward supplying theory and practice proves to protect germplasm resource,empolder and utilize the species and the other rarity species.The result reveals as follows:1)variance analysis shows:D.chinense morphological indicators significantly different account for 36.84%and almost nutrition apparatus,that's shows environment condition effect on every part of nutrition apparatus is marked,clustering analysis shows,on the level of population D.chinense has upper comparability,however on the level of individual D.chinense has some differentiation,so much as a few the plants have extremity differentiation.2)Cutting experimentation of D.chinense's shows:Useisng 1/2 purple soil and 1/2 husky river commixture cutting mediums the livability is higher than using countrified purple cutting mediums; using IBA is better than NAA;the best concentration(IBA or NAA)isl00 mg/L,when the growth hormone increase,the livability reduce. The best Cutting condition of D.chinense's:cutting mediums is 1/2 purple soil and 1/2 sand,IBA concentration is 100mg/L.3)D.chinense seed morphological indicators non-significantly different;Seed bibulous and seed capsule dialytic is well;Seed bourgeon shows:the best dipping time is 16h to 22h,it's vigor rate greater than 86%;The best seed dipping temperature is 40℃,(when the dipping temperature is 60℃～100℃,the Seed bourgeon rate is 0,shows seeds have destroyed);breeding temperature is 20℃,pH is 11 and on sunshine in favor of D.chinense seed bourgeon.4)In Flooding stress experiment,Flooding stress is non-significantly effect on young D.chinense in the forepart Flooding stress,young D.chinense's POD,SOD,proteide,solubility candy and the MDA have non-significantly change;But when the time is longer and the water is deeper,whose indicators are more significantly different,that's shows the long and deep-seated water Flooding stress is disadvantage young D. chinense alive.5)One layer shade is beneficial to early phase of the young seedling growth,when the shading time and the intensity increased,D.chinense young seedling laminae's POD,SOD,proteide,solubility sugar, proline and MDA changed obviously,that's shows the shading have a great effect on it's growth.In a word,too strong,too weak illumination is not in favor of D.chinense growth.