水分胁迫对李叶片抗氧化代谢的影响

以一年生秋红、大石早生 ,长李 84盆栽幼苗为试材 ,在李树不同水分胁迫条件下研究了李树叶片中0 -2 和H2 0 2 代谢变化。结果表明 ,随着水分胁迫的加重 ,李叶片内超氧化自由基 (0 -2 )的产生速率和过氧化氢 (H2 0 2 )的含量持续上升 ,MDA与 0 -2 和H2 0 2 之间呈显著正相关 (相关系数分别为r =0 94 16与r =0 9185 0 )。在一定范围的水分胁迫程度下 ,李可以依靠自身的保护酶系统减轻干旱对膜系统的损伤。SOD、CAT、ASAPOD、GR活性在轻度水分胁迫条件下显著上升 ,在中度水分胁迫条件下显著下降 ,ASA和GSH含量随胁迫程度加重而下降。品种间各指标比较表明 ,水分胁迫条件下 ,大石早生叶片比秋红和长李 84具有较强的抗氧化能力

Effect of Water Stress on Antioxidant Metabolism of Plum Leaves

One year old seedlings of dashizaosheng, qiuhong and changli84 were used for studying the metabolism of 0 - 2 and H 2 0 2 under water stress. The results are as follows:0 2 and H 2 0 2 content in the plum leaves increased consistently. along with the increasing of water stress, The content of MDA have significant positive correlation with 0 - 2 and H 2 0 2 , and the correlation coefficiens were r=0. 9416 and r=0. 9185, respectively. Plum decreased free radicals and the extent of membrane lipid peroxidation, depending on the system of protective enzymes under stress it can suffer to, such as SOD, CAT, GR and ASAPOD and antioxidant ASA and GSH. The activities of SOD, CAT, ASAPOD and GR were significantly inereased with water stress from slight to moderate and, appeared to be an opposite trend under severe water stress. ASA and GSH content decreased with water stress. All the results showed that the antioxidant capability of the leaves of the seedlings of dashizaosheng was better than those of qiuhong and changli84.