高温胁迫对大白菜抗氧化系统酶及可溶性蛋白质和热稳定蛋白质的影响

Effects of heat stress on antioxidant enzymes,solubk protein and heat-stable protein of Chinese cabbage

在智能人工气候培养柜中,耐热性不同的大白菜幼苗在36℃/29℃和40℃/29℃(昼/夜)下分别进行高温胁迫处理10 d,定期测定抗氧化系统酶活性以及可溶性蛋白和热稳定蛋白含量。结果表明:在不同高温处理下,大白菜的SOD和POD活性均呈升高趋势;CAT活性在36℃处理时呈现先升高后下降的变化,在40℃处理时呈下降趋势;而可溶性蛋白质含量表现为先下降后上升;热稳定蛋白含量呈下降趋势,且恢复处理后没有明显的回升,并且不同品种的含量差异不明显。耐热品种的SOD、POD、CAT活性和可溶性蛋白含量总体高于热敏品种。

Chinese cabbage seedlings with different heat tolerances were treated for 10 days respec- tively under 36 ℃/29 ℃ and 40 ℃/29 ℃ （day/night）in diurnal growth incubator and regularly deter- mined in terms of antioxidant enzymes, soluble protein and heat-stable protein. The results showed that under 36 ℃ or 40 ℃ heat stress, the activities of superoxide dismutase （SOD）and peroxidase （POD）in the seedlings presented a upward trend）the catalase（CAT）activity firstly rose and then decreased under 36 ℃ but presented a downward trend under 40 ℃ ;the soluble protein content firstly decreased and then rose;the heat-stable protein content presented a downward trend and there was not an obvious difference in content among different cultivars. Generally,the SOD, POD and CAT activities and soluble protein content of the heat-tolerant cultivars were higher than those of the heat-sensitive cultivars.