硅对低镉污染水平下水稻幼苗生长及吸收镉的影响  

Effects of Si on Rice Seedling Growth and Uptake of Cd in the Low Level of Cd Pollution

作　　者：张丽娜[1] 宗良纲[1] 任偲[1] 沈振国[2] 

机构地区：[1]南京农业大学资源与环境科学学院,江苏南京210095 [2]南京农业大学生命科学学院,江苏南京210095

出　　处：《农业环境科学学报》2007年第2期494-499,共6页Journal of Agro-Environment Science

基　　金：2003年江苏省社会发展项目"土壤污染控制及修复技术的开发应用研究"(BS2003029)

摘　　要：虽然土壤镉污染控制标准的限量较低,但镉在土壤中活性较强,容易被作物吸收,而我国低浓度镉污染的土壤面积也较大。因此我们通过水稻幼苗水培试验,研究了低镉污染水平以及不同的硅处理浓度对水稻幼苗生长和吸收镉的影响。结果表明,低浓度的镉污染虽然对水稻幼苗的生长有一定的促进作用,但幼苗体内的镉含量较高,且镉的富集系数在低浓度下也较大。因此,低浓度镉污染所引起的食品安全风险不容忽视。在镉污染条件下施加硅处理,能增加水稻幼苗蛋白质和叶绿素的含量,提高根系活力以及抗氧化酶SOD、POD的活性,但要选择适宜的浓度,硅处理浓度过高或过低时效果较差。一定浓度范围内的硅处理对于抑制水稻幼苗对镉的吸收效果非常明显,但随着硅浓度的增加,幼苗体内镉含量降低的幅度趋缓。因而从经济因素考虑,只要施加适量的硅就可以达到较好的降镉效果。The activity of Cd in soil is strong and easily absorbed by plants, though the control limit of Cd pollution is lower. And the soil areas polluted by Cd of low concentration are large in China. So effects of Cd and Si on rice seedlings growth and uptake of Cd in the solution culture at the low concentrations of Cd pollution were investigated. Low concentrations of Cd could promote rice seedling growth, but the content of Cd and the accumulation coefficient of Cd in rice seedlings were relatively higher, so that the food security risk caused by low concentrations of Cd pollution should not be overlooked. Si could increase the biomass of rice seedlings and the content of protein and chlorophyll, enhance the vitality of rice root system and the activities of antioxidant enzyme SOD and POD in the condition of Cd pollution, but the suitable concentrations of Si should be chosen since the effects of Si were weak at too high or too low concentrations. Si suppressed obviously Cd uptake by the rice seedlings in the range of silicon concentrations, but the effect decreased gradually with the increasing concentrations of Si. Thus, considering the economic factor, the suitable concentrations of Si might be chosen in decreasing the content of Cd in the rice seedlings.

关 键 词：镉 硅 水稻幼苗 安全风险 

分 类 号：X503.231[环境科学与工程—环境工程]