摘要
研究了镉对金鱼藻(Ceratophyllum demersum L.)植株生长和抗氧化酶活性的影响,用不同浓度的氯化镉溶液(镉离子浓度分别为0、2、5、10μmol/L)处理金鱼藻植株,并分别于处理后1、2、4、8 d测定金鱼藻植株的生物量和抗氧化酶活性。结果表明,低浓度镉促进金鱼藻的生长,而高浓度镉抑制金鱼藻的生长,且随着时间的延长,胁迫程度加重,镉离子浓度为10μmol/L的处理最终导致植株死亡;抗氧化酶系统对镉胁迫具有应激反应,当镉离子浓度小于5μmol/L时,超氧化物歧化酶(Superoxide dismutase,SOD)活性和过氧化氢酶(Catalase,CAT)活性均上升,而当镉离子浓度达到10μmol/L时,二者酶活性均下降。因此,当镉离子浓度小于5μmol/L时,可以诱导金鱼藻抗氧化酶活性增加,抵御氧化胁迫,使植株不受伤害。
The Cd-induced changes in growth and oxidative metabolism in Ceratophyllum demersum L. plant were studied. Plants were exposed to various concentrations of CdC12 （0, 2, 5, 10 μ mol/L）, biomass and antioxidant enzyme activity were investigated in 1, 2, 4, 8 d after Cd treatment. Results showed that low concentration of Cd promoted the plant growth, while high concentration of Cd inhibited the plant growth. As the treatment time increasing, a Cd^2＋ concentration of 10μmol/L will lead to the death of plant, the antioxidant enzyme showed responding to the Cd. Plants showed significant stimulation of the activities of antioxidant enzymes of superoxide dismutase and catalase when the concentration of Cd^2＋ was lower than 5 μmol/L, at 10μmol/L exposure, both enzymes＇ activities declined. In conclusion, increased antioxidant enzyme activity ap- pears to help plants tolerate the toxicity of Cd^2＋ with concentration lower than 5μmol/L.
出处
《湖北农业科学》
北大核心
2012年第5期977-980,共4页
Hubei Agricultural Sciences
基金
湖北省教育厅中青年基金项目(Q200727003)
湖北省自然科学基金面上项目(2007ABA364)
黄冈师范学院博士基金项目(06CD179)
