Effect of Aluminum Stress on Photosynthesis of Schima superba Seedlings and Regulation by Adding Base Cations and Phosphorous

Abstract:

In order to understand the effect of Aluminum (Al) stress on photosynthesis of Schima superba seedlings, the changes in photosynthetic characteristics of S. superba seedlings under Al stress and regulation by adding phosphorous (P) and base cations (BC) were studied. The results showed that under low Al concentration (0.25 mmol L^-1) treat ment, the contents of photosynthetic pigments (Chl a, Chl b, car), photosynthetic indexes (P_n, gs, WUE, C_i/C_a) and photoresponse parameters (P_max, AQY, R_d, LSP) all declined, and their decrement was relieved by adding either BC or BC and P. In contrast, under moderate and high Al concentrations (0.75, 1.50 mmol L^-1) treat ment, the contents of photosynthetic pigments increased, but photosynthetic parameters and photoresponse parameters decreased with increment of Al concentration. The addition of P was more efficient than that of BC in reduction of Al stress. These elucidated that BC or /and P played relative important role in alleviation of Al stress on S. superba seedlings.