2,4-表油菜素内酯对低温胁迫下辣椒幼苗抗氧化系统的影响

Effect of 2,4-epibrassinolide on Antioxidant System of Pepper Seedlings Under Low Temperature Stress

以辣椒品种"湘研16号"为试材,采用人工气候箱模拟低温环境,研究了2,4-表油菜素内酯(EBR)对低温胁迫下辣椒幼苗体内超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)活性以及抗坏血酸(As A)和谷胱甘肽(GSH)含量的影响,以期为油菜素内酯调控辣椒幼苗耐低温胁迫的机理研究提供参考依据。结果表明:抗氧化酶(SOD、POD、CAT、APX)活性在低温胁迫下高于CK,而EBR处理的叶片酶活性显著增加。同时,EBR提高了低温胁迫下辣椒幼苗叶片中抗坏血酸(As A)和谷胱甘肽(GSH)含量,降低了MDA含量。由此可见,EBR能显著增加保护酶活性和非酶抗氧化物的含量,增强植株抗氧化能力,有效缓解低温胁迫引起的膜脂过氧化伤害,降低了低温胁迫对辣椒幼苗生长的抑制作用。

Pepper cultivar ‘Xiangyan 16 ＇ was used as experimental material and grown in plant growth chamber,this study was carried out to investigate the effects of exogenously applied EBR on the growth,lipid peroxidation and antioxidant defense system of pepper seedlings under chilling stress in order to control pepper seedlings to provide reference for the mechanism of resistance to low temperature stress.The results showed that chilling stress inhibited the growth of pepper seedlings,but the foliar spray of EBR solution markedly decreased the oxidative stress under low temperature.The activities of antioxidative enzymes such as superoxide dismutase（ SOD）,peroxidase（ POD）,catalase and ascorbate peroxidase（ CAT）,and contents of ascorbic acid（ As A）and reduced glutathione（ GSH） were significantly increased by EBR during low-temperature stress. EBR significantly decreased lipid peroxidation via the induction of antioxidant defense system.The results suggested that EBR had an anti-stress effect on pepper seedlings against chilling stress which might strengthen phytoremediation approaches by enhancing plant tolerance.