花生褐斑病菌侵染对不同抗性花生活氧代谢及防御酶的影响

Effects of Cercospora arachidicola Infection on Active Oxygen Metabolism and Defense Enzymes Changes in Peanut Varieties with Different Resistance

开展了3个不同抗性花生品种经花生褐斑病菌(Cercospora arachidicola Hori)胁迫后O2-、MDA含量和防御酶系含量变化的测定,分析其与品种抗病性的相关性。结果表明,供试花生品种接种褐斑病菌1~15 d内,O2-和MDA含量均呈现先升后降的趋势。对O2-含量而言,粤油7号9 d达到最大值,花育20号7 d达到最大值,鲁花11号5 d达到最大值;对MDA含量而言,粤油7号9 d达到最大值,花育20号9 d达到最大值,鲁花11号13 d达到最大值。接种病菌后叶片中CAT、SOD、POD、PAL和PPO的含量对比分析表明,鲁花11号最高,花育20号次之,粤油7号最低;3种花生品种受侵染后病情指数与防御酶含量均呈负相关,且SOD及PAL含量在抗病品种和感病品种间存在显著差异。表明花生褐斑病菌侵染后,叶片内氧阴离子及MDA暴发时间和含量变化与花生品种抗性密切相关,抗性越强的花生品种应答时间越迅速,叶片细胞遭受破坏越小,细胞功能丧失越少;不同花生品种对褐斑病抗性水平存在差异,褐斑病菌胁迫可引起花生叶片防御酶活性及抗氧化物质含量变化,且抗性越强的花生品种防御酶含量越高;SOD和PAL含量可作为鉴定花生对褐斑病抗性的生理生化指标。

Three varieties of peanut varieties with different resistant peanut varieties were determined by the changes of O2-,MDA content and defense enzyme content after the stress of Cercospora arachidicola,and the correlation between them and the disease resistance was analyzed.The results showed that the peanut variety tested bacteria inoculated leaf spot within 1~15 d,O2-and MDA content were presented increased first and then decreased trend.Among them,for the content of O2-,Yueyou No.7 reached maximumafter 9 d,and Huayu No.20 reached maximum after 7 d,and Luhua No.11 reached maximum after 5 d;For the content of MDA,Yueyou No.7 peaked after 9 d,Huayu No.20 reached a maximum peak after 9 d,Luhua No.11 reached the maximum after 13 d.The comparative analysis of CAT,SOD,POD,PAL and PPO in the leaves after inoculation showed that Luhua No.11 was the highest,followed by the Huayu No.20,and the lowest in Yueyou No.7.There was a negative correlation between the disease index and the protective enzyme content of the three kinds of peanut varieties,and there was a significant difference between the SOD and the PAL content in disease-resistant cultivars and susceptible varieties.Indicated that the peanut leaf spot after bacteria infection,oxygen anion and outbreak time and MDA content in leaf change were closely related to the resistance of peanut varieties,the stronger the resistance of peanut varieties response time more quickly,the smaller the leaf cell damage,and cell function lost the less;Different peanut varieties for leaf spot resistance level differences,rhizoctonina bacteria stress could cause the peanut leaf defense enzymes and antioxidants content changes,and the stronger the resistance of peanut varieties defense enzyme content was higher;The content of SOD and PAL could be used as the physiological and biochemical indexes to identify the resistance of peanut to C.arachidicola.