Effects Of Different Complementary Light Measures On The Growth And Physiological And Biochemical Characteristics Of The Toona Ciliata Var. Pubescens

Toona ciliata var.Pubescens is a fast-growing industrial timber species with high economic benefit and development prospects,however,at present,the influence of different intensity and duration on Toona ciliata var.Pubescens and its response mechanism is not clear,therefore,this study discusses the different fill light measures can lead the growth,physiological and biochemical characteristics of Toona ciliata var.Pubescens to affect something,so this study with1 year old Toona ciliata var.Pubescens seedlings as the research objectd and fillingl the light as the contrast,analyzed to make up for the light of time（2 h,4 h and 6 h）and light intensity（321 lx,642 lx,963 lx,1284 lx）two volunteers factors of two factors cross experiment research of Toona ciliata var.Pubescens seedling morphological indexes,antioxidant enzyme system,photosynthetic rate,the effects of parameters such as nutrient absorption,the main results were as follows:（1）the time of finishing time has a significant influence on the biomass accumulation and nutrient element distribution of the seedlings.As the fill light the extension of time,the seedlings of Toona ciliata var.Pubescens above ground seedling height,stem diameter,leaf area,root surface area,just long,fine quality of root,leaf and root class II nitrogen content,potassium content in stem growth significantly,among them,the fill light 4 h and 6 h effect is best,fill light 2h of Toona ciliata var.Pubescens seedling growth had no significant effect on the ground.And,at the same time light,increase light intensity could significantly increase Toona ciliata var.Pubescens above ground stem diameter,leaf area,stem potassium content and underground part II grade quality and nitrogen content,of which 2D and 4D effect is best.（2）of Toona ciliata var.pubescens seedling leaf chlorophyll content,SOD activity,MDA can longer duration of lighting gradually decreased,POD activity and soluble protein content and soluble sugar content rise gradually with the extension of illumination time,to make up for 4 h and 6 h light is preferred.Under the same time processing,the intensity of light was increased,and the content of chlorophyll content,SOD activity,POD activity and soluble protein content increased gradually,and the 3D processing effect was the best.（3）within a certain range,the fill time and light intensity could significantly increase the seedlings of Toona ciliata var.Pubescens net photosynthetic rate,decrease intercellular CO₂concentration,stomatal conductance and transpiration rate,and extend as the fill light time and light intensity increases,the transpiration rate decreases gradually and then gradually recovered to normal level,to fill light 4h4D processing affect the most obvious.To sum up,fill light time of Toona ciliata var.Pubescens had a great effect on growth and physiological and biochemical characteristics,and the fill light time only within a certain range,increase the light intensity can be a positive impact on growth of Toona ciliata var.Pubescens,in all processing,fill in the night at 4 h and 6 h,2D,3D and 4Dlight intensity,the seedlings of Toona ciliata var.Pubescens were can grow better.