| This paper highlights the studies on light absorption of the leaf and the chlorophyll , response characteristics parameters of Pn/PAR and Pn/CO2 ,and with white ligh(400nm～700nm)and monocolour light quality[red light(650±5)nm,green light(550±5)nm,blue light(470±5)nm] and also analyses the photosynthetic efficiency and carboxylation effciency of red light ,green light and blue light on eggplant(Solanum melongena L.)'HEISHUAI'.The absorption value red light(660 nm) and blue light(470 nm) of chlorophyll which in the scope of the strong wavelength of 400nm～480nm and 650nm～680nm are higher , the absorption value of white light(400nm～700nm)is centered ,the green light is lower. The Vcmax and Rd to lower with the growth of the spectrum ,and the Jmax and TPU to Increased with the growth of the spectrum . Compare the LSP,LCP,AQY,PQY,CSP,CCP,CE,and dynamical parameters,the result reflects the photosynthesis efficiency of red light is higher than the green light, and the photosynthesis efficiency of green light is higher than the blue light,on account of theεof blue light is lower than green light, and green light is lower than red light.After the rapid response performance of CIRAS-2 (PP Systems, Ltd.) is made better on transient photosynthesis, the course of transient photosynthesis was measured by CO2 Step-transformation with 21%O2 or 2%O2 in solar greenhouse eggplant, in order to analyze characteristics of biochemistry and biophysics on dynamic photosynthesis. The course of CO2 uptake by a eggplant leaf displayed a oscillation during transients from stabilized state at one CO2 concentration Ca1 to other CO2 concentration Ca2, which was divided four phases, i.e. original stabilized state phases, beginning response phases, oscillation phases, and new stabilized state phases. Under 21%O2, the relative accelerating velocity of RUBP resynthesis aRUBP is zero in the original stabilized state phases; aRUBP is 1 in the new stabilized state phases; and the course of aRUBP shows S-curve between 0 and 1 in the beginning response phases and oscillation phases. Analogously, under 2%O2, the relative accelerating velocity of both Pi and RUBP (ribulose-1,5-bisphosphate) resynthesis aPi+RUBP is zero in the original stabilized state phases; aPi+RUBP is 1 in the new stabilized state phases; and the course of aPi+RUBP shows S-curve between 0 and 1 in the beginning response phases and oscillation phases. But the oscillations resulted mainly from the limit of Pi resynthesis under both 2%O2 and lower grads Ca2 of CO2 Step-transformation, and the oscillations resulted from the limit of Pi resynthesis and RUBP resynthesis under both 2%O2 and higher Caij. The lower light resuled in smaller swing in the course of oscillation because the quantity and activity of rubisco (ribulose-1,5-bisphosphate carboxyl ase/oxygenase) were limited by lower light. The time of beginning response of rubisco carboxylation ?to showed direct ratio to the resistances in the photosynthesis system and showed positive correlation in linear with Ca2.In allusion to the dynamic oscillation phenomena of photosynthes under the CO2 step disorder in eggplant ,using CO2 step starting point (Ca1) and step ending (Ca2), as well as to under different levels of light (PAR) to deal with step CO2,and combine the oscillation unit of photosynthetic feedback control system dynamic biochemical model ,analyses the oscillation parameters of dynamic photosynthesis in eggplant. According to the steady-state photosynthetic parameters, conversion the photosynthetic rate into carboxylation rate of the dynamic process can be seen ,under the lower CO2 step starting point,the time constant T of photosynthetic system is more ,but the damping , the no damping natural oscillation frequency and the damping natural oscillation frequency are smaller , so Pn and Vc fierce oscillating ; under the more CO2 step ending,ζdramatically reduce, Pn and Vc oscillation even more intense; When the light intensity increased to more than 900μmol quata·m-2·s-1,ζdramatically reduce , and the Pn and Vc oscillation has become even more fierce .Analysis shows that ,the conditions of engender photochemical oscillation are lowerζand larger T; contrary, the conditions of not to engender photochemical oscillation are higherζand smaller T; but, the critical condition of engender photochemical oscillation need medium or highζwith a larger T. In this experiment, the critical mass of CO2 step starting point , step ending and light intensity can cause to the oscillation of photosynthetic are 300μmol·L-1,900μmol·L-1,500μmol quata·m-2·s-1. On this basis, the relationship between CO2 step disorder intensity Dc and the dampingζof photosynthetic oscillation system in eggplant is exponential significant negative correlation , r =-0.8239.
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