磷和CO_2浓度变化对苦草光合生理的影响

EFFECTS OF PHOSPHORUS AND CO_2 ON PHOTOSYNTHESIS PHYSIOLOGICAL OF VALLISNERIA NATANS

为了阐明CO_2浓度和水环境要素变化对沉水植物生长的影响,采用室外模拟的方法,研究了不同磷和CO_2浓度条件下苦草叶片(Vallisneria natans)光合生理特征。实验结果表明,当水体磷浓度处于较高水平时,苦草叶片荧光参数V_j、M_o降低,参数ABS/CS_o、DI_o/CS_o、TR_o/CS_o、RC/CS、PET显著升高,其他荧光参数则无显著变化;高浓度的CO_2在显著降低苦草叶片V_j、ABS/RC、DI_o/RC、ABS/CS_o、DI_o/CS_o的同时,也显著提高了苦草叶片ψ_o、φE_o、ET_o/RC、PIABS、F_v/F_m、P_(TR)、P_(ET)的参数值,而对其他荧光参数无显著影响;在磷与CO_2交互作用方面,磷与CO_2在V_j、M_o、ψ_o、TR_o/CS_o、RC/CS和PET处存在显著的交互作用,其他荧光参数不显著。可见,磷或CO_2浓度变化均能显著影响苦草叶片光合生理状态,高浓度的CO_2可有效改善苦草叶片PSⅡ反应中心光化学性能、电子传递能力及单位有活性反应中心能量的分配,从而提高苦草叶片的光合能力;高浓度的磷可在一定程度上改善苦草叶片PSⅡ受、供体状态及电子传递性能。此外,磷和CO_2存在交互作用,协同影响苦草叶片的光合能力。

In order to evaluate the impact of changes in atmospheric and water environment on aquatic plants,we studythe photosynthesis physiological of V.natans under different phosphorus and CO2.The results showed that the fluorescenceVj、Mo of V.natans reduced when the concentration of phosphorus in the water was at a high level,but theABS/CSo,DIo/CSo,TRo/CSo,RC/CS and PET increased at the same time;high concentration of CO2significantly reducedVj,ABS/RC,DIo/RC,ABS/CSo and DIo/CSo of V.natans,but improved the level ofψo,φEo,ETo/RC,PIABS,Fv/Fm,PTR and PET.There was a significant impact of phosphorus and CO2on Vj,Mo,ψo,TRo/CSo and RC/CS of V.natans.The change of phosphorus and CO2concentration could significantly affect the photosynthetic physiological ofV.natans;high concentration of CO2can improve the performance of photosynthesis of V.natans leaves by promotingphotochemical propertieselectron,transfer process and optimizing the distribution of energy among PSⅡ;while highconcentration of phosphorus have significant promotion on the donor and acceptor of PSⅡ,and it also improved theelectron transfer properties of V.natans.Moreover,there was an interaction of phosphorus and CO2on photosyntheticphysiological of V.natans.