镉胁迫下蚕豆幼苗抗氧化能力对外源NO和H2O2 的响应

 以蚕豆品种临蚕２号为试验材料，采用土培法，研究了在镉胁迫期间蚕豆幼苗抗氧化酶（ＳＯＤ、ＣＡＴ 和ＰＯＤ）活性、脯氨酸、丙二醛和活性氧含量的动态变化过程，以探讨外源ＮＯ 和Ｈ_２Ｏ_２ 对镉毒害下蚕豆幼苗的保护效应。结果表明，０．１ｍｍｏｌ／ＬＳＮＰ（外源ＮＯ 供体）和０．０１ｍｍｏｌ／Ｌ Ｈ_２Ｏ_２ 单独处理均可缓解０．１ｍｍｏｌ／Ｌ 镉对蚕豆幼苗的氧化损伤，而二者互作处理存在正协同效应，主要表现在增强了蚕豆幼苗的保护酶活性，其中ＳＯＤ 在镉胁迫７２ｈ后活性达到峰值，比对照提高５７．８９％，ＣＡＴ 和ＰＯＤ 均在镉胁迫４８ｈ 后活性达到最大值，分别比对照提高６９．６０％和１０１．１８％；镉胁迫１２０ｈ时，与单镉胁迫处理相比，互作处理的脯氨酸含量提高了１３４．８８％，而ＭＤＡ 含量、内源Ｈ_２Ｏ_２ 含量和体内Ｏ_２· － 的产生速率下降，有效地增强了蚕豆幼苗在镉胁迫期间的抗氧化能力。

Responses of antioxidative capability in horsebean seedling to NO and H_2O_2 under Cd stress

This study investigated the change of antioxidant enzymes(including SOD,CAT and POD),proline content,MDA and reactive oxygen species(ROS) in horsebean seedlings under Cd stress,and to study the protective effect of NO and H2O2.Sodium nitro presside(SNP) was used as a NO donor.Application of SNP and H2O2,alone and in mixtures helped protect horsebean seedling leaves from Cd oxidative damage.However,treatment E showed a much better protective impact than treatments C and D,which significantly increased activi...