摘要
以水稻(宁粳1号)为试材,以萌发种子过氧化氢酶(CAT)活性、丙二醛(MDA)和H2O2含量为测定指标,研究镧对水稻种子受酸雨胁迫的缓解作用.研究结果表明,1mg.l-1的LaCl3溶液浸种处理后,水稻种子受酸雨伤害作用有所缓解,种子MDA含量和H2O2含量La(Ⅲ)组低于CK,CAT活性La(Ⅲ)>CK,表明La(Ⅲ)提高了CAT活性,加强了清除活性氧自由基的能力,使MDA含量和H2O2含量降低;同时,MDA含量和H2O2含量pH2.5>La(Ⅲ)+pH2.5>pH4.0>La(Ⅲ)+pH4.0>CK,表明酸雨胁迫使种子内部活性氧积累增加,过氧化程度加重.La(Ⅲ)处理有效缓解了其过氧化程度和活性氧的积累,且CAT活性La(Ⅲ)+pH4.0>pH4.0>La(Ⅲ)+pH2.5>pH2.5,表明酸雨胁迫使CAT活性应激升高,但高强度酸雨因其强度过大,使得酶活性下降或部分失活,La(Ⅲ)处理后缓解酶活的下降,提高酸雨胁迫下CAT活性,从而提高对H2O2的代谢能力,最终减轻种子膜脂过氧化程度,缓解酸雨对种子伤害.
Rice of ＂Ningjing No. 1＂ was used as the experimental material, and the protective effects of lanthanum on catalase（CAT） activities, the malonydialdehyde（MDA） and the H2O2 content of rice seed under acid rain stress were investigated. The results showed that parts of CAT activities, decrease MDA and H2O2 content of rice seeds were strengthened after soaked with 1 mg.l^-1 LaCl3 solution compared with control（CK）. Under the acid rain stress, the amplitude of the change in the content of MDA and H2O2 was that pH2.5 〉 La ＋ pH2. 5 〉 pH4. 0 〉 La ＋ pH4. 0 〉 CK, and the change in the activity of CAT was that La ＋ pH4. 0 〉 pH4. 0 〉 La ＋ pH2. 5 〉 pH2.5. It showed that the ability of removing the excessive free-radicals was strengthened after soaked with LaCl3 solution, while the MDA and H2O2 content were decreased. Under acid rain of pH2. 5, CAT activity was inhibited. However, La（ Ⅲ ） can effectively adjust the stability of CAT and eliminate ROS, so that it alleviated the harm to seeds by acid rain stress. The regulative effect of La （ Ⅲ ） on antioxidant enzymes such as CAT could strengthen their capacities to scavenge reactive oxygen species, improve the metabolism of ROS and decrease H2O2 contents. At the same time, it improved the proportion of membrane lipid fatty acids, decrease MDA contents. Consequently, membrane lipid peroxidation was abated.
出处
《环境化学》
CAS
CSCD
北大核心
2009年第4期535-538,共4页
Environmental Chemistry
作者简介
通讯联系人，E-mail：zhouqeco@yahoo．com．cn
