论文部分内容阅读
探讨了渗透胁迫下小麦幼苗乙烯与多胺之间是否存在底物竞争以及CoCl2和DFMA对膜脂过氧化的影响。研究结果表明,-1.0 MPa聚乙二醇(PEG)溶液对小麦幼苗根系渗透胁迫6 h时,叶片腐胺、亚精胺含量及乙烯释放量均显著提高,之后随胁迫时间延长,腐胺、亚精胺含量逐渐下降,乙烯释放量逐渐增加;当-1.0 MPa PEG溶液中加入DFMA0.5 mmol/L,在渗透胁迫过程中,相比于未加DFMA的处理,叶片腐胺和亚精胺含量均显著下降,而乙烯释放量没有显著变化;说明在-1.0 MPaPEG溶液根系渗透胁迫过程中,叶片内乙烯与亚精胺之间并不存在显著的底物竞争关系。当-1.0 MPa PEG溶液中加入CoCl22 mmol/L,乙烯释放量的增加被抑制,且腐胺、亚精胺含量显著提高;在PEG溶液中加入CoCl2还提高了叶片抗氧化酶的活力,并在胁迫至24 h时,显著降低了活性氧水平以及MDA含量,进而对细胞膜表现出保护作用。然而,在PEG溶液中加入DFMA,上述指标表现为相反的变化趋势。说明当渗透胁迫加深时,CoCl2提高多胺含量及抑制乙烯产生可以相对降低脂质过氧化程度,且能够减轻细胞膜在深度渗透胁迫下所受伤害。
The competition of substrate between ethylene and polyamine in wheat seedling under osmotic stress and the effect of CoCl2 and DFMA on membrane lipid peroxidation were discussed. The results showed that the content of putrescine, spermidine and ethylene emission in leaves of wheat seedlings under osmotic stress of -1.0 MPa polyethylene glycol (PEG) solution for 6 h were significantly increased, and then with the stress time prolonged, putrescine, During the osmotic stress, the content of spermidine gradually decreased and the ethylene release gradually increased. When DFMA 0.5 mmol / L was added to -1.0 MPa PEG solution, compared with no DFMA treatment, the contents of putrescine and spermidine But there was no significant change in the amount of ethylene released. This indicates that there is no significant substrate competition between ethylene and spermidine in the leaves under -1.0 MPa PEG solution osmotic stress. The addition of CoCl at 22 mmol / L in -1.0 MPa PEG solution inhibited the increase of ethylene release, and the content of putrescine and spermidine significantly increased. The addition of CoCl2 to the PEG solution increased the activity of antioxidant enzymes in leaves Stress to 24 h, significantly reduced the level of reactive oxygen species and MDA content, and thus showed a protective effect on the cell membrane. However, the addition of DFMA to PEG solution showed the opposite trend. The results showed that when the osmotic stress is deepened, the increase of polyamine content and the inhibition of ethylene production by CoCl2 can reduce the lipid peroxidation and reduce the damage of the cell membrane under the deep osmotic stress.