淹水胁迫对夹竹桃主要生理生化特性的影响

Effects of Flooding Stress on the Physiological and Biochemical Characteristics of Nerium indicum

摘要:

摘要：通过模拟长江滩地季节性淹水，以夹竹桃为研究对象，分析其内部生理生化指标对淹水胁迫的响应。结果表明：在淹水胁迫下超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量明显增加，与对照组相比均有极显著差异(p＜0.01）。随着淹水深度加深，SOD、POD、CAT活性和MDA含量总体上呈现增加趋势，轻度淹水和深度淹水处理间SOD活性有显著差异（p＜0.05），POD活性有极显著差异（p＜0.01），而CAT活性和MDA含量无显著差异。随着淹水时间延长，SOD活性整体上升，差异增大；POD活性36 d时达到最大值，与其它时间段有差异；CAT活性在轻度淹水处理下随着淹水时间延长差异增大；MDA含量12 d时最大，与其它时间段存在极显著差异。淹水胁迫解除后，SOD、POD、CAT等酶活性和MDA含量逐渐降到正常水平。夹竹桃在受到淹水胁迫后，体内氧化自由基的积累能迅速诱导保护酶活性的升高，有效降低毒性物质MDA的含量，说明夹竹桃具有极强的耐水淹能力。

Abstract:

Abstracts:The physiological and biochemical characteristics of Nerium indicum in different flooding stress were studied by simulating the Yangtze River seasonal flooding.The results showed that superoxide dismutase (SOD) activity,peroxidase (POD) activity,catalase (CAT) activity, malondialdehyde (MDA) contents of N. indicum in flooding stress increased significantly and there were extremely significant differences(p＜0.01) compared with the control.With the depth increasing,the activity of SOD, POD,CAT and MDA contents showed increasing trend on the whole. Between the mild flooding and deeper, SOD activity had significant difference(p＜0.05),POD activity had extremely significant difference(p＜0.01), CAT activity and MDA contents had no significant difference.As flooding time progressed,the activity of SOD increased overall and the difference was increasing.POD activity reached the maximum at 36 d,and there was different from other time. CAT activity in mild flooding had difference with prolonged flooding.MDA contents were the largest at 12 d,and there were significant difference with other time. After flooded stress removal,the enzyme activity of SOD,POD,CAT and MDA contents were gradually reduced to normal levels.After subjected to flooding stress,the oxidation of free radicals in N. indicum can rapidly induce protective enzyme activity to increase and effectively reduce the content of MDA.In a word,Oleander has strong water resistance ability.