高浓度镍对水稻幼苗生长及酶活性的影响

0.8、1.2、2.0mmol/L的Ni2+处理,水稻幼苗的生长表现出明显的阻滞现象,提示此浓度范围的Ni2+已对水稻幼苗产生了毒害.同时,水稻幼苗叶片超氧化物歧化酶(SOD)、过氧化氢酶(CAT)及抗坏血酸过氧化物酶(APX)的活性降低,H2O2和丙二醛(MDA)含量明显增多,而过氧化物酶(POD)活性却升高.统计分析表明,H2O2与MDA含量成显著正相关,而MDA

Effect of Nickel at High Concentrations on Growth and Activities of Enzymes of R ice Seedlings

The growth of rice seedlings pretreated with nickel of 0.8,1.2,2.0 mmol/L was significantly inhibited. It was suggested nickel at this concentrati on range was toxic to rice seedlings. The activity of superoxide dismutase(SOD), catalase(CAT) and ascorbate peroxidase (APX) decreased, accompanied by signific ant enhancement of H 2O 2 and malonyldialdehyde (MDA) content after treatment with nickel. However, the activity of peroxidase (POD) increased. Statistical analys is indicated that there was a significantly positive correlation between H 2O 2 a nd MDA content, and a significantly negative one between MDA content and the bi omass of rice seedlings. The results showed that nickel at high concentrations a ffected the activity level of antioxidant enzymes and disturbed the metabolism o f active oxygens in rice. The accumulation of H 2O 2 and MDA contents caused b y th e process mentioned above might be one of significant physiological changes in t oxicity lead by Ni 2 in plants, also might be an important reason by which nickel toxicity hinders the growth of plants.