氮代谢参与植物逆境抵抗的作用机理研究进展

Research progress on mechanism of nitrogen metabolism involved in plant stress resistance

近年来,植物所受到的诸如干旱、盐、高温、低氧、重金属胁迫和营养元素缺乏等环境胁迫越来越多,严重影响了植物的生长发育及作物的质量和产量。氮素是植物生长发育所需的必需营养元素,同时也是核酸、蛋白质和叶绿素的重要组成成分,其代谢过程与植物抵抗逆境的能力息息相关。氮代谢是指植物对氮素的吸收、同化和利用的全过程,是植物体内基础代谢途径之一。氮代谢主要从氮素吸收、同化及氨基酸代谢等方面参与植物的抗逆性,并通过调节离子吸收和转运、稳定细胞形态和蛋白质结构、维持激素平衡和细胞代谢水平、减少体内活性氧(reactive oxygen species,ROS)生成以及促进叶绿素合成等生理机制来影响植物抵抗非生物胁迫的能力。因此,提高植物在逆境下的氮代谢水平是减轻外界胁迫对其损伤的一种潜在途径。该文从氮素同化的基本途径出发,分别阐述了氮代谢在干旱胁迫、盐胁迫和高温胁迫等多个方面的逆境抵抗过程中的作用机理,为氮代谢参与植物抗逆性研究提供了有利参考。

In recent years,plants are facing more and more environmental stresses,such as drought,salt,high temperature,hypoxia,heavy metal stress and nutrient deficiency,which seriously affects the growth and development of plants,and the quality and yield of crops.As an essential nutrient for plant growth and development,nitrogen is also an important component of nucleic acids,proteins and chlorophyll.Its metabolic process is closely related to the ability of plants to resist adversity.Nitrogen metabolism refers to the whole process of absorption,assimilation and utilization of nitrogen in plants,which is one of the basic metabolic pathways in plants.Previous studies have shown that the nitrogen metabolism mainly participates in plant stress resistance from nitrogen absorption,nitrogen assimilation and amino acid metabolism.And it enhances the ability of plants to resist abiotic stress via regulating the absorption and transport of ions,stabilizing cell morphology and protein structure,maintaining hormone balance and cellular metabolism level,and mitigating excessive reactive oxygen species(ROS) formation.Therefore,improving the nitrogen metabolism of plants under adverse conditions is a promising approach to alleviate the damage caused by external stress.In this review,we highlight the pathway of nitrogen assimilation,and emphasize its potential roles in abiotic stress resistance from drought stress,salt stress and high temperature stress,and put forward some suggestions for future research on nitrogen metabolism involved in plant stress resistance.