细胞相容性溶质对水分胁迫下玉米根系SOD活性的促进作用

分别用脯氨酸，甜菜碱，蔗糖，甘露醇饲喂玉米根系，PEG－6000模拟水分胁迫，测定外源相容性溶质对根系SOD活性的影响。结果表明，4种溶质对水分胁迫下玉米SOD活性有不同程度的促进作用，其大小顺序为：甘露醇＞蔗糖＞甜菜碱＞脯氨酸。饲喂植株的MDA含量明显降低，降低程度的大小顺序同SOD活性一致。胁迫过程中SOD活性与MDA含量呈极显著负相关，有力地说明了SOD在干旱胁迫下对活性氧的清除和细胞膜结构的保护作用。细胞相容性物质可促进保护酶活性升高，提高植物的干旱适应性。

The increasing of compatible solutes to SOD activities in maize roots under water stress

After the maize seedlings in the mode of simulated water stress with PEG were fed with four kinds of compatible solutes,the effect of compatible solutes on SOD activity were measured in maize roots under water stress.The results showed ,the activities of SOD increased differently with compatible solutes,and the order is mannitol>sucrose>glycine betaine>proline.The lower content of MDA were found in treated plants,and the order was same to which of SOD activity.The content of MDA had negative correlation with activity of SOD during stress,which is the indication of SOD in quenching activated oxygen radicals and protecting structure of cellular membrane.Compatible solutes enhanced the activity of protective enzyme and the resistance to stress in plants.