铝胁迫对木荷幼苗光合特性的影响及添加盐基阳离子和磷的调节作用

为探讨铝(Al)胁迫对木荷(Schima superba)幼苗光合特征的影响,采用营养液水培的方法,对铝(Al)胁迫下木荷幼苗的光合响应及盐基阳离子(BC)和磷(P)的调节作用进行了研究。结果表明,在低浓度Al(0.25 mmol L–1)处理下,木荷幼苗的光合色素(Chl a、Chl b、Car)含量、光合作用参数(P n、g s、WUE、C i/C a)以及光响应特征参数(P max、AQY、R d、LSP)均呈下降趋势,添加BC或同时添加BC和P均能缓解上述参数的降低。中、高浓度Al(0.75、1.50 mmol L–1)处理,除光合色素含量呈增加趋势外,光合作用参数、光响应特征参数均下降,且下降幅度随Al浓度的升高而增大,添加P比添加BC更能有效缓解Al胁迫对木荷幼苗的影响。这揭示了BC、P在缓解木荷Al胁迫的相对重要性。

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

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.