摘要
盐胁迫是世界范围内影响作物产量和品质的主要非生物胁迫之一,如何提高作物的抗盐性已经引起全世界的关注。硅(Si)是地壳中含量仅次于氧的第二大丰富元素。在pH值低于9的介质中,硅通常以单硅酸[Si(OH)_4]的形式被高等植物吸收。尽管目前硅仍然未被认为是植物生长的必需元素,但是作为植物生长的"有益元素",硅可以缓解各种生物胁迫和非生物胁迫对植物生长发育的抑制。大量的研究表明硅可参与调控植物抗盐的生理生化代谢过程,并与一些信号物质,如乙烯、水杨酸和多胺等存在互作。主要进展如下:1)植物对硅的吸收存在主动、被动和拒绝吸收三种,硅转运蛋白在硅的吸收和转运中起到非常重要的作用,但是关于该蛋白的编码基因在更多物种中的克隆和功能研究有待于进一步开展。2)硅可以调节盐胁迫下植物体内的离子平衡,降低植物根系对盐离子的吸收和向地上部的转运,并使盐离子更均匀的分布在根系中;改善盐胁迫下根系对钙、钾、氮等营养元素的吸收,缓解盐胁迫造成的营养失调。近期一些研究表明多胺可能参与硅对根系盐离子吸收的调控。3)硅可以通过调节水通道蛋白的表达和渗透调节物质的积累提高根系对水分的吸收和向地上部的转运,改善植株的水分状况。4)硅可通过调节抗氧化酶活性,降低活性氧的产生和积累,同时可以缓解盐胁迫对光合器官和光合色素造成的损伤,保证盐胁迫下植物光合作用的正常进行。5)植物耐盐的分子机制非常复杂,涉及大量基因的表达和调控以及信号转导过程,包括蛋白质组学和转录组学在内的组学研究策略为从分子水平揭示硅缓解胁迫的机理提供了有力的技术手段。转录组和蛋白质组学的研究表明硅可以通过调控转录因子、激素等相关基因的表达及蛋白的翻译和修饰来调控植物对盐胁迫的快速响应,提高植物的抗盐能力。6)硅吸收突变体的应用有助于我们更好的了解硅在调控植物生理生化代谢中所发挥的作用。
High salinity is one of the major abiotic stressful factors affecting crop growth and productivity in agriculture system of the world.Therefore,improving the salt-tolerance of crops has attracted worldwide attention.Silicon element(Si)is the second most prevalent element in the earth’s crust excepting for oxygen.When the pH of a solution is less than 9,silicon is usually absorbed in the form of silicic acid[Si(OH)4]in plants.Although silicon has not been recognized as essential element for higher plants,it is considered to be a‘beneficial element’.Especially,silicon can increase plants resistance to multiple stresses and improve the growth and development of plants under stress conditions.Many studies suggested that silicon actively involves the physiological and biochemical processes in plants under salt stress,and silicon has a crosstalk with the signaling molecules that include ethylene(ET),salicylic acid(SA),and polyamines(PAs).In this paper,the silicon accumulation and transportation,the beneficial regulatory role of Si are reviewed when the plants are subjected to the salt stress.Major progresses:1)Si could be absorbed by plants in active,passive and rejective routes.Silicon transporters play important roles in silicon uptake,but the silicon uptake systems and their functions in different plant species need more investigations.2)Silicon could alleviate salt damage through mediating ion balance under high salinity.Application of silicon can specifically decrease the uptake and transport of Na from roots to shoots,and make evenly distribute Na+crossing the whole root section.In addition,silicon affects the uptake of some essential nutrients(e.g.Ca,K,N)in plant to alleviate adsorption competition between salt ions and essential nutrients.Recent studies suggested that polyamines play a regulatory role in promoting uptake of silicon-mediated nutrients under salt stress.3)Both the up-regulation of silicon-mediated aquaporin gene expression and osmotic adjustment play important roles in increasing water uptake.4)Silicon application alleviates oxidative stress damage to the plants by regulating the antioxidant defense and decreasing the production of reactive oxygen species(ROS).Meanwhile,silicon could alleviate the salt stress damage to the photosynthetic apparatus and prevent salt stress from destroying pigment,and thus improving the photosynthetic process.5)Omics-based technologies,transcriptomic and proteomic analyses,provide powerful tools for better understanding the responsive mechanisms of silicon-triggered in alleviating environmental stresses at the molecular level.Both the transcriptome and proteome studies reveal that silicon could regulate the plants responses to salt stress through modulating the expressions of transcription factors and hormone-related genes as well as the translation of associated proteins.6)The utilization of silicon mutant will be helpful to better understand the regulatory role of silicon in the physiological-biochemical metabolic processes in plants.
作者
朱永兴
夏雨晨
刘乐承
尹军良
马东方
ZHU Yong-xing;XIA Yu-chen;LIU Le-cheng;YIN Jun-liang;MA Dong-fang(College of Horticulture and Gardening/Engineering Research Center of Ecology and Agricultural Use of Wetland,Ministryof Education,Yangtze University,Jingzhou,Hubei 434000,China;State Key Laboratory for Biology of Plant Diseasesand Insect Pests /Institute of Plant Protection,Chinese Academy of Agriculture Sciences,Beijing 100193,China;College of Agriculture,Yangtze University,Jingzhou,Hubei 434000,China)
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2019年第3期498-509,共12页
Journal of Plant Nutrition and Fertilizers
基金
国家自然科学基金项目(31701911)
植物病虫害国家重点实验室2017年度开放课题基金项目(SKLOF201707)
长江大学湿地生态与农业利用教育部工程研究中心开放基金项目(KF201707)资助
关键词
硅
大数据分析
盐胁迫
离子平衡
氧化损伤
水分代谢
光合
分子机制
silicon
big data analysis
salt stress
ion balance
reactive oxygen species
water metabolism
photosynthesis
molecular mechanism
