预处理及复水对PEG胁迫下水稻抗氧化系统的影响

Effects of Pretreatment and Rehydration on Antioxidant System of Rice Under PEG Stress

【目的】此文研究了植物的抗旱机制及干旱对植物抗氧化系统的影响,在农业生产中有着重要的意义。【方法】以水稻作为实验材料,研究了经过PEG预处理的水稻叶片及复水后抗旱相关的抗氧化酶活性及抗氧化物质含量的影响。【结果】未预处理组的SOD、POD活性有所提高,而预处理组及预处理-复水组SOD活性无明显变化,且POD活性有所增强却幅度小于未处理组;预处理组与预处理-复水组CAT活性持续上升而未预处理组的CAT活性先上升后下降;4组水稻叶片的APX和GR活性都先升高后下降;预处理组的AsA与GsH含量在胁迫0 h时均高于对照组和未预处理组的含量,随后4组水稻叶片的AsA含量都在下降;预处理-复水组的GsH含量略微升高后下降,其余3组水稻叶片的GsH含量也都缓慢下降。【结论】前期的PEG预处理可以使水稻叶片抗氧化系统活性增强产生抗性,清除ROS,并且水稻叶片可以对抗性产生记忆,使其可以更好地应对随后的干旱胁迫。

【Objective】This paper aimed to study the drought resistance mechanism of plants and the effect of drought on plant antioxidant systems for the important role in agricultural production.【Method】Taken rice as the experimental material,the effects of PEG-pretreated rice leaves on drought-resistance-related antioxidant enzyme activities and antioxidants content after re-water were studied.【Result】The activities of SOD and POD in untreated groups increased,while the activity of SOD in the pretreatment group and the pretreatment-rehydration group did not change significantly,and the activity of POD increased but the extent was smaller than that in the untreated group.The activity of CAT in the pretreatment-rehydration group continued to increase,while the activity of CAT in untreated group increased first and then decreased.The activities of APX and GR in the leaves of the four groups increased first and then decreased.The contents of AsA and GsH in the pretreatment group under stress 0 hour was higher than that in the control group and the untreated group,and the AsA content of the four groups of rice leaves decreased.The GsH content of the pretreatment-rehydration group decreased slightly,and the GsH content of the rice leaves of other three groups decreased,which were also slowly falling.【Conclusion】The early PEG pretreatment can increase the resistance of the rice leaf antioxidant system to generate resistance and eliminate ROS,and the rice leaves can produce resistance to memory,so that they can better respond to subsequent drought stress.