外源H_(2)O_(2)对盐胁迫下棉花幼苗生理特性的影响  

Effect of Exogenous Hydrogen Peroxide on the Physiological Characteristics of Cotton Seedlings under Salt Stress

作　　者：肖陈耀东 刘涛[1] 刘仕志 张淑英[1] XIAO Chenyaodong;LIU Tao;LIU Shizhi;ZHANG Shuying(Agricultural College,Shihezi University,Shihezi 832003,China)

机构地区：[1]石河子大学农学院,新疆石河子832003

出　　处：《华北农学报》2024年第5期93-101,共9页Acta Agriculturae Boreali-Sinica

基　　金：国家自然科学基金项目(42067021)。

摘　　要：为探明外源H_(2)O_(2)对NaCl胁迫下棉花幼苗的生理调节机制,以棉花品种新陆早48号为供试材料,使用室外盆栽法,设置盐胁迫(NaCl,浓度梯度0,100,200 mmol/L)和H_(2)O_(2)(浓度梯度0,0.005,0.010,0.020,0.050 mmol/L)两因素随机组合,探究棉花幼苗鲜质量、干质量、叶绿素含量、叶绿素荧光参数、光合气体参数、抗氧化酶活性和渗透调节系统的变化规律。结果表明,外源H_(2)O_(2)有效缓解盐胁迫对棉花幼苗生长的抑制效应,提高棉花幼苗叶绿素含量、光合气体参数、叶绿素荧光参数,维持棉花幼苗光合作用正常运行,保证了干物质的积累;同时,外源H_(2)O_(2)提高抗氧化酶(POD、APX、CAT)活性,加速清除棉花幼苗体内ROS,降低了电解质渗出率、MDA含量及Pro、游离氨基酸、SS等渗透调节物质含量,提高棉苗抗盐性。其中0.020 mmol/L外源H_(2)O_(2)对棉花幼苗所受盐胁迫缓解作用最佳。综上,外源H_(2)O_(2)通过提高盐胁迫棉花幼苗光合性能,保持棉花幼苗稳定的光合作用,维持棉花幼苗体内ROS产生与消除的动态平衡,从而提高棉花幼苗对盐胁迫的适应性。In order to investigate the physiological regulation mechanism of exogenous H_(2)O_(2)on the cotton seedlings under NaCl stress,the cotton variety Xinluzao 48 was used as the test material in an outdoor potting method.Two-factor random combinations of salt stress(NaCl,concentration gradients of 0,100,200 mmol/L)and H 2O 2(concentration gradients of 0,0.005,0.010,0.020,0.050 mmol/L)were set,to study the change rule of fresh weight,dry weight,chlorophyll content,chlorophyll fluorescence parameters,photosynthetic gas parameters,antioxidant enzyme activities and osmotic regulation system of cotton seedlings.The results showed that exogenous H_(2)O_(2)effectively alleviated the inhibitory effect of salt stress on the growth of cotton seedlings,increased chlorophyll content,photosynthetic gas parameters and chlorophyll fluorescence parameters of cotton seedlings,maintained the normal operation of photosynthesis of cotton seedlings and ensured the accumulation of dry matter.Meanwhile,exogenous H 2O 2 could increase the activity of antioxidant enzymes(POD,APX,CAT),accelerated the removal of ROS from cotton seedlings.Exogenous H 2O 2 reduced the electrolyte leakage rate,MDA content,the content of osmoregulation substances such as pro,free amino acid and SS,and improved the salt resistance of cotton seedlings.Among all treatment,0.020 mmol/L exogenous H_(2)O_(2)had the best effect in alleviating the salt stress suffered by cotton seedlings.In summary,exogenous H_(2)O_(2)improves the adaptation of cotton seedlings to salt stress by improving photosynthetic performance,keeping stable photosynthesis in cotton seedlings,and maintaining the dynamic balance between ROS production and elimination in cotton seedlings.

关 键 词：棉花幼苗 盐胁迫 外源H_(2)O_(2) 光合特性 抗氧化酶系 

分 类 号：S562.01[农业科学—作物学]