铜胁迫对小麦幼苗生长和抗氧化系统的影响

摘要

押以小麦种子为材料，通过液体培养实验探究铜对小麦幼苗生长和抗氧化系统的响应，揭示小麦幼苗对铜胁迫的生理抗性机制。结果表明，低浓度铜对小麦幼苗生长具有一定的促进作用，随着铜浓度的进一步增大和培养时间的延长，小麦幼苗的生长量明显减少，根和叶片中的膜脂过氧化产物丙二醛(MDA)、超氧化物歧化酶( SOD)、过氧化物酶( POD)、过氧化氢酶( CAT)和脯氨酸( Pro)的含量均明显升高，与对照相比达到5%或1%的差异显著性水平，这些活性物质在根和叶中的变化趋势基本一致，其含量除POD在根中分布大于叶中外，其余均表现为在叶中的分布大于在根中的分布。在过量Cu2+引起胁迫的过程中，抗氧化系统各成分通过相互协同配合，对铜胁迫进行有效的抵御，对自身进行严密的保护。%with wheat seeds as experimen tal material and through liquid culture experiment, the study explored the effect of copper stress on the growth and antioxidant system of wheat seedlings and revealed the physiological mechanism of resistance to that stress. The results showed that low concentration of copper had a certain role in promoting the growth of wheat seedlings, but with the further increase of Cu concentration and prolongation of culture time, the growth of wheat seedlings decreased signifcantly, while the content of malondialdehyde (MDA) resorted from membrane lipid peroxidation, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and proline (Pro) increased significantly and the content difference reached significant level (5% or 1% ). The changing trend of these active substances are basically the same in roots and leaves of the wheat seedlings, except the content of POD in roots is more than that in leaves, the rest of active substances distributed in leaves were more than that in roots.In the process of the stress caused by excessive Cu2+, antioxidant system together with each other to alleviate the toxic effects of oxidative stress caused by excess copper and protect plant closely.