硅对盐胁迫下玉米幼苗叶片膜脂过氧化和保护系统的影响

Effects of Silicon on Membrane Lipid Peroxidation and Protective Systems in The Leaves of Maize Seedlings Under Salt Stress

采用砂基培养方法 ,研究硅对盐胁迫下玉米幼苗叶片膜脂过氧化和保护系统的影响 .结果表明 ,硅使盐胁迫下玉米幼苗叶片保护酶 (SOD、POD、CAT、As A- POD)活性显著上升 ,抗坏血酸(As A)含量明显增加 ,玉米叶片的丙二醛 (MDA)含量和超氧阴离子自由基 (O2 · -)产生速率显著下降 ,叶片质膜透性降低 .硅提高了盐胁迫下玉米幼苗叶片叶绿素含量和叶绿素 a/ b值 ,增强了光合速率 .因此硅可减轻盐胁迫对玉米幼苗的伤害 .

This paper studied the effects of silicon on the membrane lipid peroxidation and protective systems in the leaves of maize seedlings under salt stress. It showed that under the salt stress the activities of superoxide dismutase(SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (AsA-POD) and the content of ascorbic acid (AsA) in maize leaves increased significantlyh when soluble silicon(Si) was added to the salt-contained solution. However, in the leaves of Si-treated maize seedlings, the content of malondialdehyde(MDA) and the producing rate of superoxide radical(O_(2~·)^-) decreased markadly and the plasma membrane permeability reduced as compared to the contron(salt-treated alone). Additionally, the increments in chlorophyll contents, Chl.a/b ratio and photosynthesis rate were observed in the Si-treated seedlings. Thus, the damage by salt stress on maize seedlings could be alleviated by Si addition.