Effects of Soda and Saline-Alkali Stress on Photosynthetic Characteristics and Yield of Rice
Rice varieties Changbai 9 and Jinongda 667 were used as the test materials,and four treatments of black soil(CK),light saline(LS),moderate saline(MS)and severe saline(SS)were set up by potting method.The dry matter,leaf area,yield,leaf chlorophyll content,gas exchange parameters and chlorophyll fluorescence parameters of rice were measured to investigate the response mechanisms of photosynthetic physiology of rice under different levels of soda salinity stress.The results showed that rice leaf area,chlorophyll content,net photosynthetic rate(Pn)and stomatal conductance(Gs),dry matter and yield in photosynthetic gas exchange parameters decreased significantly;and intercellular CO2 concentration(Ci)increased significantly with increasing salinity.Chlorophyll fluorescence kinetic curves of WK at point K and VJ at point J,and initial reduction rate of QA(Mo)were significantly increased,performance index of rice leaves(PIABS)was significantly decreased,quantum yield and efficiency(φPo,φRo,ΨEo)showed a decreasing trend with the increasing salinity,and heat dissipation ratio(φDo)showed an increasing trend.Compared with CK,the yield of Changbai 9 under soda salinity stress decreased on average by 16.85％to 48.85％in two years,and by 17.00％to 53.10％in Jinongda 667.The yield components of rice were significantly reduced in seed-setting rate,effective panicle number and grains number per panicle.
RiceSoda and saline-alkali stressPhotosynthesisPhotosystem ⅡChlorophyll fluorescence
NETL
NSTL
万方数据
