The Influence Of Environment Factors To The Growth And The Color Expression Of Cercis Canadensis 'Forest Pansy'

In this paper, we studied on Cercis canadensis 'Forest Pansy',under different environmentparameters, measured the light response curve,Diurnal variation of photosynthetic characters,pigment content, Carbohydrate content, Conductivity, Leaf relative water content and so on,and discussed the Suitable conditions and the rule of color expression of leaves in Cerciscanadensis 'Forest Pansy'. The results revealed as follows:1. The Photosynthesis of Cercis canadensis 'Forest Pansy'(1)The light saturation point of grafts and cultivates in Cercis canadensis 'Forest Pansy'were dividually 1800 and 1500μmol·m^-2·s^-1,their light compensation point dividually were25.532 and 30.949μmol·m^-2·s^-1, and the apparent quantum efficiency were dividually 0.0423and 0.0316. Cercis canadensis 'Forest Pansy' had high saturation point and low lightcompensation point, Data therefore indicated that it enjoyed light and beared certain darkday.(2) The diurnal variation of Pn was "two-peaks-type", Pn was reduced sharply at noon insummer, and it appeared remarkably "noon-drop" phenomenon.(3) Linear return showed whatinfluent Pn most was Cond and the next is Ci.2. The Physiolocal Characters in Cercis canadensis 'Forest Pansy' under different lightintensities(1)Shading reduced the net photosynthesis;(2)Saturation point of plant fell off along withthe light intensities reduced; the apparent quantum efficiency got their result under differentconditions as follow: 70％light intensity＞100％light intensity＞40％light intensity＞15％light intensity, suitable shade could enhance the apparent quantum efficiency, but shadingexcessively lessened the apparent quantum efficiency of plant. (3)The weaker the light Was, themore the anthocyanin-content of leaves was, meanwhile the contents of anthocyanis, sugar andthe starch were all decreasing.3. The Physiolocal Characters in Cercis canadensis 'Forest Pansy' under different soildrought conditions(1)It was result from soil drought that Pn max, light saturation point (LSP) and apparentquantum efficiency were dropped, whereas light compensation point (LCP) were increased.(2)With the water stress increased,the content of soil water and the relative content of leaveswater lessened obviously, as well as saving water was destroyed completely. (3)Under Soildrought conditions,the relative membranes permeability of leaves got stronger than ever.4. The Physiolocal Characters in Cercis canadensis 'Forest Pansy' under different hightempreture conditions (1)High tempreture rendered that Pn max, light saturation point (LSP) and apparentquantum efficiency descended, but light compensation point (LCP) rose. (2)The research ontreatment temperature and the rate of injured cell indicated that the grafts and cultivates ofCercis canadensis 'Forest Pansy' high semi-lethal temperature was dividually 53.611℃and54.670℃. (3)With the time of high tempreture increasing, the anthocyanis degradated,so lowtempreture was good to anthocyanins stability.