| In this paper,one year old Cinnamomum migao H.W.Li seeding were used as the main research object,using the method of control experiment,setting up three light processing,each light treatment consists of three water treatment,studying its response mechanism of moisture and light,which providing theoretical guidance to large-scale culture.The seedling height,ground diameter,the relative water content of leaf,biomass and root cap ratio,photosynthetic pigment content,permeability material,electrical conductivity,MDA,antioxidant system,light response curves were analyzed.The results of the study were summarized as follows:Under the same light processing,with the intensification of water stress,leaf fight the drought stress by reducing the relative water content of leaf,seedling height,ground diameter and biomass,increasing the water saturation deficit,the content of chlorophyll,soluble sugar and free amino acid,the activity of MDA,antioxidant enzymes and the root-shoot ratio,the photosynthetic and transpiration rate gradually declined,inter cellular CO2 concentration decreased.With time extension of water stress,the height and ground diameter of Cinnamomum migao H.W.Li seeding increased slowly,the relative water content of leaf showed a trend of declining after rising,photosynthetic pigment first rising after downward,osmotic regulation substances,plasma membrane permeability and antioxidant system gradually rising.Under the three water treatment period which providing full exposure(L1),with the intensifying of drought stress,the rising of temperature,the declining of air humidity,blade through rolled leaf,stomatal closure and even death to fight the drought,but the plants undergrowth,seedling height,ground diameter and biomass reduce sharply.Under the treatment of W1 moisture,with the intensification of shade,ground diameter,biomass,the relative water content of leaf showed a trend of first increasing after dropping,root-shoot ratio and water saturation first deficit then rising.Under thetreatment of W2 moisture,with the weakness of light,seedling height,the relative water content of leaf showed a trend of first rising then declining,soluble sugar and MDA first lower then higher,ground diameter,biomass and the soluble protein gradually reducing,photosynthetic pigment,conductivity and free amino acid increasing,the enzyme activity of three indicators,except CAT,the activity of SOD and POD was increasing gradually.Under the treatment of W2 and W3 moisture,these indexes have no big difference.Under the different light processing,Tr and Gs have different change,the content of Tr under the treatment of L2W1 and L2W2 lower than under the treatment of L1W1 and L1W2.In full exposure,transpiration rate were rising,but appear the phenomenon of light inhibition,results in the decrease of photosynthetic rate.Under the same light processing, with the intensification of the drought,the higher of the Ci, Under the same water level,with the loss of the light,the value of the Ci showed a trend of first rise after falling.Under the treatment of L2 light,compared with the control,the value of Ci lower obviously,further illustrate that Cinnamomum migao H.W.Li shall grow better,photosynthesis better under moderate shade.After using correlation analysis to analyze the every physiological and biochemical indexes under the treatment of light and water stress.It is known that the relative water content of leaf,electrical conductivity,soluble sugar,soluble protein and MDA,free amino acid,SOD,POD,CAT has significant negative correlation,it is showed that after stress processing,the relative water content of leaf have significantly correlation with the physiological and biochemical indexes,these indexes have theory significance to consider Cinnamomum migao H.W.Li resistance to drought and shade.Under the treatment of moderate shade and moisture(L2W1) all the morphological and physiological and biochemical indexes showed Cinnamomum migao H.W.Li grow well,indicated that Cinnamomum migao H.W.Li have resistance to the negative. |
PDF Full Text Request