外源亚精胺对涝胁迫下玉米幼苗根系无氧呼吸代谢的调控效应  

Regulating Effects of Exogenous Spermidine on Anaerobic Respiratory Metabolism in the Roots of Maize Seedling under Water-logging Stress

作　　者：杜红阳[1,3] 程明明[1,2] 杨青华[3] 刘怀攀[1] 

机构地区：[1]周口师范学院生命科学与农学学院,植物遗传与分子育种重点实验室,河南周口466001 [2]郑州大学生命科学学院,河南郑州450001 [3]河南农业大学农学院,河南郑州450002

出　　处：《华北农学报》2015年第4期110-116,共7页Acta Agriculturae Boreali-Sinica

基　　金：国家自然科学基金项目(31271627);国家公益性行业(农业)科研专项(201203077);河南省教育厅自然科学基金项目(2011A180033)

摘　　要：为了探讨多胺提高玉米抗涝性的机制,以2个抗涝性不同的玉米品种(郑单958,抗涝性较弱;浚单22,抗涝性较强)为材料,设置正常处理、涝胁迫处理、涝胁迫+亚精胺(1 mmol/L)3个处理,分别在处理0,2,4,6 d取幼苗根测定相对电解质渗漏率、无氧呼吸酶活性(乳酸脱氢酶(LDH)、丙酮酸脱羧酶(PDC)和乙醇脱氢酶(ADH))、代谢产物(乙醇和乳酸)和亚精胺(Spd)含量,并测定幼苗相对干物质增长速率,研究了亚精胺对涝胁迫下玉米幼苗根系呼吸代谢的调控效应。结果表明:在正常生长情况下,2个玉米品种幼苗根系中无氧呼吸酶活性、代谢产物和亚精胺含量均无明显变化,且在2个品种间无明显差异;涝胁迫处理后,2个玉米品种幼苗根系中无氧呼吸酶活性以及乙醇、乳酸、亚精胺含量增加,且抗性较弱的郑单958的LDH活性和乳酸含量增加幅度大于抗性较强的浚单22,而抗性较强的浚单22的ADH活性和乙醇、亚精胺含量增加幅度大于抗性较弱的郑单958;涝胁迫+亚精胺处理后,2个玉米品种幼苗根系中PDC、ADH活性以及乙醇、Spd含量升高,LDH活性和乳酸含量下降,且抗性比较弱的郑单958的变化幅度大于抗性比较强的浚单22。结果显示,亚精胺与涝胁迫下玉米幼苗根系的呼吸代谢之间存在密切关系,亚精胺一方面可以通过提高玉米幼苗根系中无氧呼吸代谢酶PDC和ADH活性以及增加乙醇和Spd含量减少有害物质乙醛对细胞的伤害;另一方面可以通过降低LDH活性抑制乳酸的过量产生,避免细胞质的过度酸化,降低细胞膜的伤害,从而缓解涝胁迫对玉米幼苗造成的伤害,促进干物质的积累和玉米幼苗的生长。In order to elucidate the mechanism that polyamines improve the resistance of maize seeding to wa-ter-logging,two maize cultivars,Zhengdan No.958 （ZD 958：water-logging-sensitive）and Xundan No.22 （XD 22：water-logging-tolerant）,were used as experiment materials,three treatments were implemented with control（CK）, water-logging（WL）and WL ＋Spd （1 mmol /L）.On the 0,2nd,4th,6th of treatment,the activities of anaerobic res-piration enzymes （pyruvate decarboxylase：PDC,lactic dehydrogenase：LDH and alcohol dehydrogenase：ADH）and the contents of metabolite （ethanol and lactate）and Spd were detected in maize seedling roots,and the relative drought matter increase rate （RDMIR）of maize seedlings was also calculated.The regulating effects of exogenous spermidine（Spd）on the anaerobic respiration metabolism in maize seedling roots were studied under water-logging stress.The results showed the activities of anaerobic respiration enzymes,the contents of metabolite and Spd in two＆amp;nbsp;maize seedling roots had no obvious changes under normal growth conditions,and there was also no obvious differ-ence between two cultivars;however,under water-logging stress,these enzyme activities,ethanol,lactate and Spd contents in two maize seedling roots increased,and the increases in ADH activity,ethanol and Spd contents in XD 22 was more significant than those in ZD 958,but the increases in LDH activity and lactate content in ZD 958 was more significant than that in XD 22;after treatment with Spd,the activity of ADH,ethanol and Spd contents in-creased and the LDH activity and lactate content decreased in two maize seedling root,the changes in these indexes in ZD 958 were more significant than those in XD 22.The results suggest that there are close relationships between polyamines and anaerobic respiration metabolism in maize seedling root under water-logging stress.On the one hand,Spd could decrease the injury of acetaldehyde on plant cell via improving the activity of ADH and increasing ethanol

关 键 词：亚精胺 涝胁迫 玉米 无氧呼吸 

分 类 号：S513[农业科学—作物学] Q945.79[生物学—植物学]