玉米不同组织过氧化氢酶水杨酸敏感性的差异和外源水杨酸处理提高 …

水杨酸（ｓａｌｉｃｙｌｉｃａｃｉｄ,ＳＡ）介导的植物抗病反应不仅要求高水平的水杨酸,而且要求有效的ＳＡ信号传导机制或途径,研究结果表明,玉米（ＺｅａｍａｙｓＬ．）植株的内源ＳＡ水平低,不同玉米组织的过氧化氢酶表现出对ＳＡ敏感性的差异,玉米叶的过氧化氢酶活性对ＳＡ敏感,而玉米根的过氧化氢酶活性对ＳＡ很不敏感,玉米过氧化氢酶同功酶基因的表达呈组织特异性,在玉米叶片内存在一个类似烟草和拟南芥的有效信号感     

水杨酸诱导植物抗病性的新进展

水杨酸是一种重要的能激活一系列植物抗病防卫反应的内源信号分子.首先介绍了水杨酸在植物抗病性中的作用,并从水杨酸与过氧化氢及其代谢酶类相互作用的角度初步探讨了水杨酸诱导植物抗病性的分子机理,最后概述了目前这一领域中需要进一步研究的若干问题.     

植物系统获得的抗病性和信号传导

植物在长期的进化过程中,需要不断地抵抗病原微生物的侵害。在这种长期相互影响的共进化过程中,植物逐渐形成一系列复杂而行之有效的保护机制来抵御病原微生物的侵染。在植物抵御病原微生物侵染的过程中,宿主植物的抗病基因（R）产物与病原微生物无毒基因（Avr）产物的...     

外源一氧化氮、水杨酸和过氧化氢对烟草叶片游离氨基酸和可溶性蛋白含量的影响

测定了NO、SA和H2O2三种信号分子对烟草氮代谢产物游离氨基酸、脯氨酸和可溶性蛋白质含量的影响。结果表明：NO、SA和H2O2能调节烟草脯氨酸、游离氨基酸和可溶性蛋白质含量。低浓度的NO和H2O2处理后12h能提高脯氨酸含量,而较高浓度的NO、SA和H2O2处理降低烟草脯氨酸和游离氨基酸含量;三者对脯氨酸、游离氨基酸和可溶性蛋白质含量的影响具有相似性。     

水杨酸诱导普通菜豆镰孢菌枯萎病抗病性的研究

普通菜豆是人类主要食用豆类之一,其营养价值高、栽培面积大。镰孢菌枯萎病是普通菜豆典型的土传病害,给普通菜豆生产带来严重损失。水杨酸(SA)被认为是诱导植物抗病反应的重要信号分子之一,参与植物的过敏反应(HR)和系统获得性抗性反应(SAR)。本研究通过不同植物激素处理普通菜豆BRB-130,结果表明,SA处理普通菜豆叶片使植株根中SA的含量升高,并显著提高植株对枯萎病原菌FOP-DM01菌株的抗性。SA诱导普通菜豆根组织中苯丙氨酸解氨酶、过氧化物酶活性及过氧化氢的含量显著升高,从而诱导普通菜豆产生HR和SAR。因此,SA作为普通菜豆抗病信号途径中重要的化学激活因子,能够显著提高普通菜豆对枯萎病原菌的抗病性,为发展环境友好型化学农药提供新的思路。     

鲫鱼不同组织过氧化氢酶同工酶活性的比较

对鲫鱼的心、鳃、肉、卵四种组织进行聚丙烯酰胺凝胶电泳并用KMnO4 法染色 (定性 ) ,同时与FeCl3-K3Fe(CN) 6 系统法进行对照 ,发现两种染色法得到的酶带具有一致性。然后用钼酸铵比色法测定四种组织中过氧化氢酶的活性 (定量 ) ,发现四种组织中过氧化氢酶的活性大小依次为 :心 >卵 >鳃 >肉。     

添加稳定剂提高过氧化氢酶的稳定性

为提高过氧化氢酶的应用稳定性和储藏稳定性,选用无机盐、醇类、大分子有机物、糖类、表面活性剂等物质为备选稳定剂,进行不同浓度的单因素实验,然后进行正交实验,又研究了蛋白酶抑制剂对过氧化氢酶酶液中蛋白酶的抑制效果,得到了最佳的稳定剂组合乙酸钠80 g/L,吐温20 2 mL/L,乙二醇80 mL/L,明胶1 g/L,六偏磷酸钠5 g/L,使蛋白酶得到抑制,提高了过氧化氢酶的稳定性.对最佳组合进行了酶的应用稳定性和储藏稳定性实验,在60℃处理15 min,酶活残留率为75.2％提高了43.2％;在常温25℃放置3个月,酶活残留率为90％,提高了67％,酶的应用稳定性和储藏稳定性得到了很大提高,为工业化的生产和应用奠定了基础.     

在耐热性诱导中豌豆叶片过氧化氢和水杨酸含量与质膜ATP酶活性的变化及相互关系

在高温锻炼(37℃,2h)过程中,豌豆(Pisum sativum L.)叶片过氧化氢(H_2O_2)和游离态水杨酸(SA)含量与质膜ATP酶(H~ -ATPase)活性都有一个高峰,H_2O_2的迸发早于游离态SA的积累,而质膜H~ -ATPase活性高峰的出现则迟于SA高峰;活性氧清除剂、抗氧化剂、质膜NADPH氧化酶抑制剂和H_2O_2的淬灭剂预处理均可有效地阻止高温下H_2O_2和SA的积累以及质膜H~ -ATPase活性的增加。根据以上结果推测,H_2O_2、质膜H~ -ATPase和SA均参与耐热性诱导相关的信号传递,前者作用于SA的上游,而后者在SA下游起作用。     

乙基纤维素微胶囊对过氧化氢酶固定化的研究

以乙基纤维素作膜材,用液中干燥法使过氧化氢酶微胶囊化。研究了微胶囊化操作条件对酶活性的影响。通过测定微胶囊化酶的释放曲线,证明微胶囊膜对过氧化氢酶具有较好的固定性能力。固定化酶用于催化底物过氧化氢分解,测定米氏常数为０．５５ｍｏｌ／Ｌ。     

Salicylic Acid and Disease Resistance in Plants

SA has been shown to play an important signaling role in the activation of various plant defense responses following pathogen attack. These responses include the induction of local and systemic disease resistance, the potentiation of host cell death, and the containment of pathogen spread. The mechanisms through which SA mediates these effects are varied and can involve alterations in the activity or synthesis of certain enzymes, increased defense gene expression, potentiation of several defense responses, and/or the generation of free radicals. Through the analysis of mutant plants exhibiting aberrant responses to pathogen infection, many genes encoding products involved in the SA-mediated defense pathway(s) have been isolated. In addition, mounting evidence suggests that certain defense responses can be activated via a SA-independent pathway(s). This review focuses primarily on recent discoveries pertaining to the SA signaling pathway(s) leading to disease resistance; however, a very brief discussion of the SA-independent pathway (s) and its ability to cross-talk with the SA pathway is also presented.     

水杨酸在植物抗病中的作用

水杨酸是一种重要的能激活植物抗病防卫反应的内源信号分子。本文首先介绍了水杨酸的基本性质及水杨酸在植物抗病中的作用,然后从水杨酸与水杨酸结合蛋白的相互作用以及水杨酸介导的信号传导途径与非水杨酸介导的信号途径等方面初步探讨了水杨酸诱导植物抗病性的作用机制,最后总结了研究水杨酸作用机制对植物抗性生理和抗性分子生物学发展的意义。     

水杨酸在植物抗病中的作用

水杨酸是一种重要的能激活植物抗病防卫反应的内源信号分子,本文首先介绍了水杨酸的基本性质及水杨酸在植物抗病中的作用,然后从水杨酸与水杨酸结合蛋白的相互作用以及水杨酸介导的信号传导途径与非水杨酸介导的信号途径等方面初步探讨了水杨酸诱导植物抗病性的作用机制,最后总结了研究水杨酸作用机制对植物抗性生理和抗性分子生物学发展的意义。     

Differential Accumulation of Salicylic Acid and Salicylic Acid-Sensitive Catalase in Different Rice Tissues

We previously proposed that salicylic acid (SA)-sensitive catalases serve as biological targets of SA in plant defense responses. To further examine the role of SA-sensitive catalases, we have analyzed the relationship between SA levels and SA sensitivity of catalases in different rice (Oryza sativa) tissues. We show here that, whereas rice shoots contain extremely high levels of free SA, as previously reported (I. Raskin, H. Skubatz, W. Tang, B.J.D. Meeuse [1990] Ann Bot 66: 369-373; P. Silverman, M. Seskar, D. Kanter, P. Schweizer, J.-P. Metraux, I. Raskin [1995] Plant Physiol 108: 633-639), rice roots and cell-suspension cultures have very low SA levels. Catalases from different rice tissues also exhibit differences in sensitivity to SA. Catalase from rice shoots is insensitive to SA, but roots and cell-suspension cultures contain SA-sensitive catalase. The difference in SA sensitivity of catalases from these different tissues correlates with the tissue-specific expression of two catalase genes, CatA and CatB, which encode highly distinctive catalase proteins. CatA, which encodes a catalase with relatively low sequence homology to the tobacco SA-sensitive catalases, is expressed at high levels exclusively in the shoots. On the other hand, in roots and cell-suspension cultures, with northern analysis we detected expression of only the CatB gene, which encodes a catalase with higher sequence homology to tobacco catalases. The role of catalases in mediating some of the SA-induced responses is discussed in light of these results and the recently defined mechanisms of catalase inhibition by SA.     

玉米粗缩病改良新抗源T877的抗性评价

玉米粗缩病是我国玉米产区的一种重要病害。本研究利用自然接虫法初步鉴定了41份玉米自交系对粗缩病的抗性,并对其中有代表性的10份材料进行了3个播期的试验。筛选出3份高抗、4份抗、3份中抗材料,大部分材料(占75.6%)表现为感和高感,抗性较好的材料属于PB亚群。高抗粗缩病自交系T877在不同年份、不同播期间抗性稳定,以此为亲本育成苏玉19等新品种。     

Induction of Systemic Resistance in Pea to Pea Powdery Mildew by Exogenous Application of Salicylic Acid

Exogenous application of salicylic acid (SA) solutions to pea leaves induced systemic resistance to Erysiphe pisi. reducing by 20–30% the percentages of fungal germlings that successfully infected untreated leaves of SA-treated plants. SA concentrations of 1.5 and 15 mM were similarly effective, but 0.15 mM had no detectable effect. While 15 mM SA solutions were phytotoxic. 1.5 mM solutions caused no apparent damage indicating that resistance induction was not due to tissue damage. The induced resistance persisted for at least 13 days after treatment, but excision of treated leaves 1 day after SA application prevented full induction of systemic resistance, and the resistance was not expressed if untreated leaves were inoculated fewer than 3 days after SA application. The effect of SA was transmitted to leaves at nodes both above and below treated leaves. Chemical induction of systemic resistance may provide an additional means for controlling pea diseases.     

玉米抗病虫性的分子标记研究进展

本文评述了近十年来利用分子标记研究玉米抗病虫性的进展。主要论述了抗病虫性基因定位中出现的问题、通过分子标记研究这些基因在基因组中的分布和基因组结构等,提出了玉米抗病虫性基因的标记和定位的发展方向和策略。     

水杨酸与植物抗非生物胁迫

本文综述了水杨酸在诱导植物抗（耐）非生物胁迫如重金属、臭氧、紫外辐射、过冷、热激、水分亏缺和盐胁迫等方面的进展,并探讨了水杨酸作用的分子、生理机制。     

水杨酸与植物抗非生物胁迫

本文综述了水杨酸在诱导植物抗（耐）非生物胁迫如重金属、自氧、紫外辐射、过冷、热激、水分亏缺和盐胁迫等方面的进展,并探讨了水杨酸作用的分子、生理机制。