多胺对盐胁迫下植物的作用

摘要

Salt stress is one of the worldwide abiotic stresses resulting in growth re-duction, chlorosis, wilting, and plant death. These exhibitions might result from men-tal toxicity and osmotic stress induced by salt. The two aspects of stress would af-fect vital metabolic pathways, reactive oxygen species scavenging system, lipid per-oxidation and photosynthetic apparatus. Thus, exploring ways to improve crop pro-ductivity or al eviate harmful effects under salt is one of the major areas of concern. Polyamines are aliphatic nitrogen organic cations which are implicated in a wide range of plant physiological processes such as morphogenesis, flower differentiation and initiation, they also play a role in biotic or abiotic stress responses. At the physiological level, polyamines modify the activities of many enzymes included in salt stress response and can bond to photosynthetic apparatus, thus changing the photosynthetic efficiency. At molecular level, polyamines can modify expressions of the polyamine-related genes directly or indirectly. Significant researches had been done to understand the effects of polyamines on plant salt resistance, but several questions stil need to be answered. The present review is focused specifical y on the effects of polyamines on physiological and molecular changes in plants under salt stress.%盐胁迫能导致植物生长减弱、失绿、萎蔫甚至死亡，是世界范围内的一种非生物胁迫。导致植物出现上述情况的原因在于盐胁迫导致的离子毒害和渗透胁迫。这两方面的胁迫会影响植物的代谢过程，活性氧清除，膜脂过氧化和光合机构的损伤。因此探索提高植物盐胁迫下的产量及适应性的方法是农业生产的一个重要方面。多胺类物质参与众多的植物生理过程，对于植物生物与非生物逆境也有重要作用。盐胁迫下多胺能调节多种酶的活性并且能够与光合机构结合，缓解盐胁迫对光合作用的影响。在分子水平上，多胺能够调节多胺相关基因表达量的改变。关于多胺缓解盐胁迫下植物受损害的研究已取得许多进展，但仍然有许多问题没有解决。该综述主要介绍多胺在植物抗盐胁迫的生理和分子生物学上的作用。