Interactive Effects Of Light With Nitrogen On The Growth And Physiological Characteristics Of Bletilla Striata Thunb. Rchbf

Bletilla.striata Thunb.Rchb.f is belonging to Orchidaceae,Perennial herb,Total raceme,flower is beautiful,Its dry phosphorus stems can be used as a medicine,Its main ingredients contain mannan,starch,naphtha,etc.It is warmly welcomed by public due to its convergence bleeding,the effect of detumescence raw muscle in medicine.Its also a good material to forests economic and medicine model,As always,the government pays great attention to its promotion and development.For the moment,the related cultivation techniques?irrigationnn,fertilization,etc.?coordinated with B.stri-ata are rarely reported,and it is worthwhile to explore to determine whether these differences in light conditions will affect the responses of B.stri-ata to nitrogen factors.This thesis is on pot experiment on Bletilla.striata with controlled light and nitrogen.It studies the effects of nitrogen on its growth,on its photosynthesis and psychological characteristics and also studies seasonal effects on its growth to look for appropriate conditionds of light and nitrogen for its growth to enhance nitrogen utilizat ion,as well as to provide a basis for the cultivation and promotion of B.striata.Research results show that:?1?Light and nitrogen application rate can significantly affect the growth of B.striata,morphological and physiological characteristics.Effect of nitrogen application level is higher,and significantly coupling effect between both.The light of the reasonable combination of nitrogen can promote B.striata root and leaf development,and thus enhanced the photosynthetic productivity,growth and biomass of B.striata.Results show that,When light for nitrogen combination:Light intensity is 60%?natural?,nitrogen application rate is 0.5 g/strain,best at seedling stage growth.?2?Light intensity dramatically affects the nitrogen factor response law of seedling stage.Specifically,when its sunny,the appropriate nitrogen application significantly promote the growth of B.striata.In the process of B.striata seedling,nitrogen application scheme formulation needs to consider the actual light conditions.?3?Taken together,B.striata seedling growth under low nitrogen and high light combination treatment is better,The leaf area per plant,root length,root diameter,root volume,etc in the specular and Nnitrogen combination performance is better,The weak light environment and excessive nitrogen fertilizer B.striata poor growth.?4?In the case of high light+N combination,the photosynthetic characteristics of Bletilla striata were the highest.Tr reached the maximum(2.85?mol·m^-2·s^-1),Ci under this treatment reached a maximum of 279.54?mL.L-1,Cond maximum(0.17?mol·m^-2·s^-1).The content of malondialdehyde and superoxide dismutase in Bletilla striata was the best under high light+zero N combination.The N concentration and N content of the leaves reached the maximum at the combination of high light+high N.The fertilization efficiency of N is the best condition in the combination of high light and low N.