CAJ | 학술논문

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。
위료탐토다알제고옥미항로성적궤제，이2개항로성불동적옥미품충（정단958，항로성교약；준단22，항로성교강）위재료，설치정상처리、로협박처리、로협박＋아정알（1 mmol ／L）3개처리，분별재처리0，2，4，6 d 취유묘근측정상대전해질삼루솔、무양호흡매활성（유산탈경매（LDH）、병동산탈최매（PDC）화을순탈경매（ADH））、대사산물（을순화유산）화아정알（Spd）함량，병측정유묘상대간물질증장속솔，연구료아정알대로협박하옥미유묘근계호흡대사적조공효응。결과표명：재정상생장정황하，2개옥미품충유묘근계중무양호흡매활성、대사산물화아정알함량균무명현변화，차재2개품충간무명현차이；로협박처리후，2개옥미품충유묘근계중무양호흡매활성이급을순、유산、아정알함량증가，차항성교약적정단958적 LDH 활성화유산함량증가폭도대우항성교강적준단22，이항성교강적준단22적 ADH 활성화을순、아정알함량증가폭도대우항성교약적정단958；로협박＋아정알처리후，2개옥미품충유묘근계중 PDC、ADH 활성이급을순、Spd 함량승고，LDH 활성화유산함량하강，차항성비교약적정단958적변화폭도대우항성비교강적준단22。결과현시，아정알여로협박하옥미유묘근계적호흡대사지간존재밀절관계，아정알일방면가이통과제고옥미유묘근계중무양호흡대사매 PDC 화 ADH 활성이급증가을순화 Spd 함량감소유해물질을철대세포적상해；령일방면가이통과강저 LDH 활성억제유산적과양산생，피면세포질적과도산화，강저세포막적상해，종이완해로협박대옥미유묘조성적상해，촉진간물질적적루화옥미유묘적생장。
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 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 and Spd contents in maize seedlings roots,on the other hand,Spd could inhibit excessive lactate to avoid ex-cessive acidification of cytoplasm via reducing LDH activity,relieve the injury of water-logging on maize seedling, and promote drought matter accumulation and the growth of maize seedling.