大豆耐盐机理及相关基因分子标记

大豆耐盐涉及多种生理代谢途径.耐盐大豆能够通过Cl-排除、控制Na 的吸收和转运、合成渗透调节物质、改变细胞膜膜脂组分及相关酶类的活性等多种形式来适应盐胁迫;野生大豆群体具有盐腺,从形态结构上适应盐逆境;大豆-根瘤菌共生体在盐胁迫下通过互作来提高整体的耐盐性.分子生物学技术应用于大豆耐盐研究,已获得了一些与耐盐相关基因连锁的分子标记.广泛搜集筛选大豆栽培种和野生种资源,利用分子生物学技术和基因工程提高大豆耐盐性,将成为未来大豆耐盐研究的主要内容.     

栽培大豆种质资源耐盐性的研究进展

评价、筛选并利用栽培大豆的耐盐种质资源,对开发利用盐渍土具有极其重要的意义。本文从耐盐性评价方法、耐盐的生理生化基础、耐盐的分子生物学基础及耐盐种质的筛选与创新等4方面,对栽培大豆的耐盐性研究进展进行了系统综述。同时对栽培大豆耐盐性研究现存的问题与今后的发展方向进行了讨论,以期为栽培大豆耐盐性研究提供参考。     

盐胁迫下植物基因的表达与基因工程研究进展

在各种环境胁迫中,盐胁迫是造成作物减产的严重环境因素之一。随着植物分子生物学快速发展,植物耐盐性研究已深入到耐盐相关基因的克隆、基因的结构分析以及基因表达领域。文中就与植物耐盐性密切相关的小分子渗透物质、晚期胚胎发生富集蛋白(LEA)、通道蛋白、盐胁迫相关基因、信号传导基因和转录因子研究作了综述。同时对植物耐盐性研究作了简单的展望。     

盐胁迫下植物基因的表达与基因工程研究

在各种环境胁迫中,盐胁迫是造成作物减产的严重环境因素之一。随着植物分子生物学快速发展,植物耐盐性研究已深入到耐盐相关基因的克隆,基因的结构分析以及基因表达领域。文中就与植物耐盐性密切相关的小分子渗透物质、晚期胚胎发生富集蛋白(LEA)、通道蛋白、盐胁迫相关基因、信号传导基因和转录因子研究作了综述。同时对植物耐盐性研究作了简单的展望。     

耐盐转基因植物研究进展

高盐是限制作物生长、发育和产量的最严重的非生物胁迫之一。长期以来,改善作物的耐盐性一直是一个伟大的目标。然而,由于耐盐反应是一个极为复杂的过程,过去,通过传统的育种和遗传工程取得的成功有限。近十年来,由于分子生物学的发展,发现了一些与耐盐相关的新基因,对于这些基因的表达方式及其在耐盐反应中的作用已逐步得到了解,这为转基因工程提供了新的材料。通过控制耐盐相关基因在植物体内的表达,已获得了一些提高耐盐性的转基因植物,展示了诱人的前景,但该领域研究仍然存在许多困难和问题,文章重点讨论耐盐转基因植物的进展。     

野生大豆耐盐性研究进展

野生大豆对于拓宽大豆种质遗传基础和丰富大豆种质基因库具有重要意义.该文从野生大豆的资源概况及优良性状、耐盐机理和利用野生大豆提高栽培大豆耐盐性等三个方面,对近年来国内外有关野生大豆耐盐性的解剖结构、生理基础、分子生物学基础等方面的研究进展进行了系统综述,并提出野生大豆通过茎叶表皮上的"腺体"及对Na+和Cl-的排斥性,实现对盐渍环境的颉颃作用.较强的抗氧化能力、大豆异黄酮代谢和耐盐基因也是其适应盐渍环境的重要原因.今后应对野生大豆耐盐机理的遗传学基础进行深入研究,并通过种群保护以保障野生大豆的发掘鉴定和创新利用.     

植物盐胁迫应答蛋白质组学研究的技术策略

土壤盐渍化是限制植物生长和分布的关键因素之一.揭示植物响应盐胁迫的分子机理是借助分子生物学手段提高植物耐盐性的基础,也是当前植物生理与分子生态学研究的热点问题.高通量的蛋白质组学技术体系包括双向电泳技术、蓝色自然胶电泳技术、双向荧光差异凝胶电泳技术、液相色谱技术,以及各种生物质谱技术,已经被广泛应用于植物应答盐胁迫研究,为解析植物耐盐分子机制提供了重要信息.本文综述了应用于植物盐胁迫响应蛋白质组学研究的技术策略.     

植物耐盐相关基因克隆的研究进展

随着植物分子生物学快速发展,植物耐盐性研究已深入到耐盐相关基因的克隆、基因的结构分析以及基因表达特性等领域.目前,耐盐相关基因的克隆工作进行的如火如荼,有很多植物的耐盐基因已经被克隆,这些已克隆的耐盐相关基因涉及盐胁迫信号传导、基因表达的调控因子、渗透调节物质、胚胎发育晚期丰富蛋白LEA(Late-embryogensiS-abundant)等,本文就盐胁迫涉及的信号传导基因、基因表达调控因子等的克隆研究进展作一简要概述.     

氯化钠胁迫下野生和栽培大豆幼苗体内的多胺水平变化

以通用的较耐盐的栽培大豆Lee68品种和对盐敏感的野生大豆N23232种群为参照,研究了盐胁迫下耐盐野生大豆BB52种群幼苗体内多胺(PAs)组分、含量及多胺氧化酶(PAO)活性的变化。结果表明,盐胁迫下BB52幼苗根PAs中Put和Spm含量下降较Lee68和N23232显著,但Spd含量下降较少．BB52叶片PAs中Put含量下降,Spd上升,(Spd+Spin)／Put值增加和Put／PAs值降低幅度与耐盐性呈正相关趋势．盐胁迫下,各材料根和叶中PAO活性上升,N23232上升最明显．探讨了多胺水平与BB52耐盐性的关系。     

栽培大豆和野生大豆耐盐性及离子效应的比较

以国际上常用的耐盐大豆（Glycine max L.)品种Lee68为对照,在发芽期和苗期两个阶段,利用发芽指数、指害指数和耐盐系数等指标对一年生具盐腺野生大豆（Glycine soja L.)和部分栽培大豆（Glycine max L.)及某些野生大豆品系或品种的耐盐性进行了比较,讨论了耐盐指标的可行性。从离子效应方面比较了Na^ 和Cl^-对大豆发芽率的影响,并对具盐腺野生大豆的耐盐机理进行了初步分析。结果表明,大豆品种的耐盐性在发芽期和苗期无一致相关性。轻度等渗胁迫下,Na^ 对种子发芽率的抑制作用大于Cl^-,而重度等渗胁迫下则相反。通过减少由根系吸收的Na^ 、Cl^-向叶片的运输,维持叶片中较高含量的K^ ,减轻盐离子毒害,可能是具盐腺野生大事耐盐的主要生理机制之一。     

Salt Tolerance in Soybean

Soybean is an Important cash crop and its productivity is significantly hampered by salt stress. High salt Imposes negative impacts on growth, nodulation, agronomy traits, seed quality and quantity, and thus reduces the yield of soybean. To cope with salt stress, soybean has developed several tolerance mechanisms, including: (I) maintenance of ion homeostasis; (ii) adjustment in response to osmotic stress; (iii) restoration of osmotic balance; and (iv) other metabolic and structural adaptations. The regulatory network for abiotic stress responses in higher plants has been studied extensively in model plants such as Arabidopsis thaliana. Some homologous components involved in salt stress responses have been identified in soybean. In this review, we tried to integrate the relevant works on soybean and proposes a working model to descdbe Its salt stress responses at the molecular level.     

Salt Tolerance in Soybean

Soybean is an Important cash crop and its productivity is significantly hampered by salt stress. High salt Imposes negative impacts on growth, nodulation, agronomy traits, seed quality and quantity, and thus reduces the yield of soybean. To cope with salt stress, soybean has developed several tolerance mechanisms, including: (I) maintenance of ion homeostasis; (ii) adjustment in response to osmotic stress; (iii) restoration of osmotic balance; and (iv) other metabolic and structural adaptations. The regulatory network for abiotic stress responses in higher plants has been studied extensively in model plants such as Arabidopsis thaliana. Some homologous components involved in salt stress responses have been identified in soybean. In this review, we tried to integrate the relevant works on soybean and proposes a working model to descdbe Its salt stress responses at the molecular level.     

辣椒CaNAC36转录因子耐盐性分析

【目的】辣椒是中国种植面积最大的蔬菜作物,随着土地盐碱化问题的日趋严重,加强辣椒耐盐机制研究对促进产业可持续发展具有重要意义。因而,急需加快辣椒耐盐相关关键基因的功能研究。【方法】研究组前期挖掘到与辣椒耐盐性相关的转录因子CaNAC36,在此基础上,以耐盐辣椒PI201224和敏盐辣椒PI438643为供试品种,克隆获得CaNAC36全长gDNA和cDNA序列,通过荧光定量分析CaNAC36及可能的互作基因在盐胁迫条件下不同组织部位的表达情况,并进一步结合生物信息学分析探究CaNAC36及其互作基因之间存在的潜在关系。【结果】结果表明,CaNAC36序列在耐盐和敏盐材料中DNA和cDNA同源性分别为99.86%和100%;荧光定量的结果表明,CaNAC36在耐盐材料根和茎组织中表现为诱导上调表达,在敏盐材料根和叶中表现为诱导下调表达;对可能与CaNAC36存在互作关系的48个基因的注释信息进行分析后,发现跨膜蛋白、转运蛋白、水孔蛋白、氯离子通道蛋白、解毒蛋白等14个基因可能与CaNAC36存在功能互作。进一步分析发现,在PI201224和PI438643盐胁迫处理不同时间点、不同组织中,5个相关基因（Capana08g002748、Capana00g004514、Capana09g000275、Capana07g001450、Capana02g001031）的表达呈现显著差异。同时发现,CaNAC36及5个关联基因启动子域含有大量的逆境相关顺式作用元件。【结论】结合基因克隆、基因表达水平分析以及生物信息学分析,表明CaNAC36是辣椒响应盐胁迫的重要转录因子,并可能与其他基因相互作用以提高植株的耐盐性,可为深度研究辣椒耐盐性以及选育耐盐品种提供数据支撑。     

Salt Tolerance in Selected Vegetable Crops

Ensuring adequate food production is a major issue in the context of an increasing human population, limit to the areas of new land that can be cultivated, and loss of existing cultivated lands to abiotic stresses. Of these stresses, salinity consistently has the greatest impact in reducing the area of cultivated land, often due to inappropriate irrigation techniques. To increase food supply, there is a need to produce salt-tolerant crops, which can grow successfully on salt-affected lands. Among crops, vegetables possess a central position in the human diet because of their nutritional value providing vitamins, carbohydrates, proteins, and mineral nutrients. There are many vegetable crops of local importance around the world but others that are very widely cultivated. All of these vegetable crops are affected by salinity more or less severely. Salinity affects every aspect of vegetable crop development including their morphology, physiological function and yield. Although efforts have been made to understand the mechanisms of salt tolerance in vegetable crops, less attention has been paid to these than to the staple crops. Where attempts have been made to improve salt tolerance of vegetables, the strategies have ranged from exogenous application of fertilizers, compatible solutes or plant growth regulators, to use of advanced molecular techniques for genetic modifications. This review focuses on the responses of pea, okra, tomato, eggplant, pepper, carrot, broccoli, cauliflower, and potato to salt stress and the strategies being used to enhance their salt tolerance.     

植物根系耐盐机制的研究进展

植物根系能够摄取土壤环境中的养分与水分,在植物的生长发育中起重要的作用。植物根系由于直接与土壤环境相接触会受到非生物胁迫较大的影响。盐胁迫是主要的非生物胁迫之一,对植物根系会产生较大的伤害。综述根系在组织形态和细胞水平上对盐胁迫的应答,以及根系响应盐胁迫的信号传导途径、转录因子与基因,对植物根部耐盐机制的解析和植物耐盐基因工程工具基因的挖掘具有重要意义。     

Salt tolerance in crop plants: new approaches through tissue culture and gene regulation

Recent approaches to study of salinity tolerance in crop plants have ranged from genetic mapping to molecular characterization of gene products induced by salt/drought stress. Transgenic plant design has allowed to test the effects of overexpression of specific prokaryotic or plant genes that are known to be up-regulated by salt/drought stress. This review summarizes current progress in the field in the context of adaptive metabolic and physiological responses to salt stress and their potential role in long term tolerance. Specifically considered are gene activation by salt, in view of proposed avenues for improved salt tolerance and the need to ascertain the additional influences of developmental regulation of such genes. Discussion includes the alternate genetic strategy we have pursued for improving salinity tolerance in alfalfa (Medicago sativa L.) and rice (Oryza sativa L.). This strategy combines single-step selection of salt-tolerant cells in culture, followed by regeneration of salt-tolerant plants and identification of genes important in conferring salt tolerance. We have postulated that activation or improved expression of a subset of genes encoding functions that are particularly vulnerable under conditions of salt-stress could counteract the molecular effects of such stress and could provide incremental improvements in tolerance. We have proceeded to identify the acquired specific changes in gene regulation for our salt-tolerant mutant cells and plants. One particularly interesting and novel gene isolate from the salt-tolerant cells is Alfin1, which encodes a putative zinc-finger regulatory protein, expressed predominantly in roots. We have demonstrated that this protein binds DNA in a sequence specific manner and may be potentially important in gene regulation in roots in response to salt and an important marker for salt tolerance in crop plants.     

Effects of P-Glycoprotein Inhibitor and Elicitor on the Salt Tolerance of Rice Seedlings

Hymexazol （3-Hydroxy-5-methylisoxazole） as the main ingredients of HI （elicitor） was used to screen salt-tolerant species from 122 salt-tolerant rice （Oryza sativa L.） cultivars under specific inducement. The results showed that the local species R6 is highly induce-sensitive. R6 showed salt tolerance during the whole growth period by using 1.0% NaCI solution after HI treatment. Cyclosporin A （CsA） and verapamil （VP） as P-glycoprotein （PGP） inhibitors and rifampin （RFP） as a PGP elicitor were used to treat R6. The morphological traits, structure of the root, physiological characteristics of leaf and root systems, the content of endog- enous hormones indole-3-acetic acid （IAA） and abscisic acid （ABA） etc. show that CsA, VP and RFP had remarkable effects on the rice＇s salt tolerance. Hymexazol inducement （HI） can improve the rice＇s salt tolerance greatly and make it more salt-resistant.