冷胁迫对棉苗抗氧化酶活性及丙二醛含量的影响

以早熟、中熟、晚熟3种不同熟性的5个棉花品种幼苗进行4°C冷胁迫处理,通过分析胁迫条件下过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量的变化,比较不同棉花品种苗期抗冷性差异。结果表明,在4°C胁迫处理的3天中,POD活性呈现先上升后下降的趋势,冷处理第二天中熟品种N177的POD活性显著增强,为对照的239.9%;SOD活性在处理的3天中,都有不同程度的增加,其中晚熟品种K-1活性变化最显著,为对照的162.4%;不同品种MDA含量均随着处理时间的延长而增加,早熟品种N52增加幅度最小,综合分析,5个棉花品种中,早熟品种N52抗冷性较强。

Effects of Cold Stress on Activity of Antioxidant Enzymes and Malondialdehyde (MDA) Content in Cotton Seedling

In order to analyse the effects of cold treatment on peroxidase(POD),superoxide dismutase(SOD) activity and malondialdehyde(MDA) content,in this experiment,five cotton cultivars including one precocious,two medium-and two late-mature cultivars were treated with 4°C for 0 h,24 h,48 h and 72 h,respectively.The results indicated that there were significant differences of POD and SOD activity and MDA content among different cotton cultivars with the extension of low-temperature stress time.At primary stage of cold stress,the POD activity exhibited an increasing trend.The POD activity was significantly increased after cold treatment in N177,about 239.9% of CK.However,at the late stage of cold stress,the POD activity significantly declined.The SOD activity gradually increased in five cotton cultivars.In particular,the SOD activity of K-1 significantly increased after cold treatment,about 162.4% of CK.The MDA content of different cultivars increased with the treatment time,but the increasing rate of precocious cultivar 52 was the lowest.Collectively,N52 had significant cold resistance.