二苯基氯化碘盐及过氧化氢预处理对缺钾环境下甘薯幼苗抗氧化系统的影响  

Effect of Pretreatment with DPI and H 2O 2 on the Antioxidant System of Sweetpotato Seedlings in a Potassium Deficient Environment

作　　者：郭鹏宇 张强强 靳容[2] 赵鹏 王静[2] 朱晓亚 于永超 刘明 吴德祥[1] 唐忠厚[2] GUO Pengyu;ZHANG Qiangqiang;JIN Rong;ZHAO Peng;WANG Jing;ZHU Xiaoya;YU Yongchao;LIU Ming;WU Dexiang;TANG Zhonghou(School of Agronomy,Anhui Agricultural University,Hefei 230036,China;Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai District,Xuzhou 221131,China)

机构地区：[1]安徽农业大学农学院,安徽合肥230036 [2]江苏徐淮地区徐州农业科学研究所,江苏徐州221131

出　　处：《华北农学报》2024年第S1期108-116,共9页Acta Agriculturae Boreali-Sinica

基　　金：国家甘薯产业技术体系养分管理(CARS-10);青年科学基金项目(32001482)。

摘　　要：为了研究缺钾胁迫下活性氧(ROS)对甘薯生长和抗氧化系统的影响,进一步揭示活性氧调控甘薯缺钾胁迫下的抵御机制。选用低钾耐受型品种徐薯32和低钾敏感型品种宁紫薯1号2种甘薯品种为试验材料,通过人工气候室内水培的方式确保试验过程中环境因素保持一致,采用外源H_(2)O_(2)和二苯基氯化碘ROS抑制剂(DPI)预处理甘薯幼苗之后再进行缺钾处理,检测缺钾处理后不同时间点下甘薯根系内源H_(2)O_(2)相对含量、抗氧化基因表达水平及酶活力指标的变化,记录甘薯的形态特征,探索ROS信号对缺钾胁迫下甘薯苗期生长的影响。研究结果表明,缺钾处理下,甘薯生物量降低,叶色变淡;甘薯幼苗根系ROS相对浓度在第14天荧光强度表现最高;甘薯根系中抗氧化相关基因的表达量普遍升高,H_(2)O_(2)预处理表达量升高更显著;与-K处理相比,H_(2)O_(2)和DPI预处理均可提高甘薯叶片中的抗氧化酶活性,不同种酶活性在缺钾处理21 d内的变化趋势有所差异;不同处理的影响效应存在品种差异。H_(2)O_(2)可作为胁迫信号分子,提高甘薯幼苗抗氧化基因表达水平,提高抗坏血酸酶(APX)、超氧化物歧化酶(SOD)和过氧化物酶(POD)的酶活,从而清除多余ROS,有效缓解缺钾胁迫对甘薯幼苗生长的抑制,而DPI可以抑制内源H_(2)O_(2)的产生,维持抗氧化酶活,保护甘薯幼苗ROS酶促清除系统,避免组织的氧化损伤。In order to investigate the effects of reactive oxygen species(ROS)on the growth and antioxidant system of sweetpotato under potassium deficiency stress,and further reveal the defense mechanism of ROS regulation in sweetpotato under potassium deficiency stress.This study selected two sweetpotato varieties,Xushu32(low potassium tolerant)and Ningzi 1(low potassium sensitive),as experimental materials.The experiment was conducted in an artificial climate chamber using hydroponic cultivation to ensure consistent environmental conditions.After pretreatment with exogenous H_(2)O_(2) and diphenyl chloroiodate(DPI),ROS inhibitor,the sweetpotato seedlings were subjected to potassium deficiency treatment.The changes in relative H_(2)O_(2) content,antioxidant gene expression levels,and enzyme activity indicators in sweetpotato roots at different time points after potassium deficiency treatment were measured.The morphological characteristics of sweetpotato were recorded to explore the effects of ROS signaling on the growth of sweetpotato seedlings under potassium deficiency stress.The results showed that under potassium deficiency treatment,the biomass of sweetpotato decreased and leaf color lightened.The relative concentration of ROS in sweetpotato seedling roots showed the highest fluorescence intensity on the 14th day.The expression levels of antioxidant-related genes in sweetpotato roots generally increased,with a more significant increase in expression levels after H_(2)O_(2) pretreatment.Compared with-K treatment,both H_(2)O_(2) and DPI pretreatment could enhance the activity of antioxidant enzymes in sweetpotato leaves,and different enzyme activities showed different trends within 21 days of potassium deficiency treatment.There were varietal differences in the effects of different treatments.The experimental results showed that H_(2)O_(2) could act as a stress signaling molecule to increase the expression level of antioxidant genes and the enzymatic activities of APX,SOD and POD in sweetpotato seedlings,thus scavengin

关 键 词：甘薯 钾胁迫 H_(2)O_(2) 活性氧 二苯基氯化碘盐 

分 类 号：S531[农业科学—作物学]