硫化物胁迫对马来眼子菜生理生化指标的影响

Effects of sulfide (S^(2-)) on physiological and biochemical indicators of potamogeton malaianus

为研究水体中硫化物(S2-)对马来眼子菜的胁迫作用,通过静态模拟试验,分析了不同S2-水平(0、0.05、0.10、.2和0.3 mmol/L)培养下马来眼子菜叶绿素总量、丙二醛和2种抗氧化酶(过氧化氢酶、过氧化物酶)的活性变化。研究发现,当试验水体中c(S2-)≤0.05mmol/L时,马来眼子菜叶绿素总量随培养时间呈增加趋势,当c(S2-)>0.2 mmol/L时,植物生长会受到明显影响,叶绿素浓度下降,光合作用受到抑制;不同S2-浓度组中马来眼子菜丙二醛浓度在暴露时均显示应激效应,膜质过氧化程度随水体S2-浓度及其暴露时间的增加而加重;在c(S2-)≤0.05 mmol/L时,2种抗氧化酶的活性得以维持或提高,当c(S2-)≥0.1 mmol/L时,马来眼子菜体内抗氧化酶活性下降,抗逆性降低,表现为剂量-负效应关系。

In order to study the effects of sulfide on the physiological and biochemical process of potamogeton malaianus,the effects of different concentrations of sulfide（0.0 mmol/L,0.05 mmol/L,0.1 mmol/L,0.2 mmol/L,and 0.3 mmol/L） on the contents of total chlorophyll,malonaldehyde（MDA）,and activities of two antioxidant enzymes（POD and CAT） in potamogeton malaianus were investigated using the static hydroponic method.The results showed that the content of total chlorophyll in potamogeton malaianus increased with training time when sulfide concentration was less than or equal to 0.05 mmol/L;the growth of the plant was apparently affected,the concentration of chlorophyll decreased,and photosynthesis of potamogeton malaianus was inhibited at all times when sulfide concentration was higher than 0.2 mmol/L;MDA content of potamogeton malaianus in exposure displayed stress effects,and the degree of cytoplasmic membrance peroxidization of potamogeton malaianus increased with the concentration of S2-and the exposure time;activities of two types of antioxidant enzymes were maintained or increased when sulfide concentration was less than or equal to 0.05 mmol/L;and with higher sulfide concentration（≥ 0.1 mmol/L）,the activities of antioxidant enzymes decreased,and there was a certain dose-negative response relationship between them.