蜡蚧轮枝菌侵染黑刺粉虱体表过程的显微观察

采用扫描电镜研究了蜡蚧轮枝菌侵染黑刺粉虱成虫的过程。结果表明：接种蜡蚧轮枝菌孢子12h后,附着在虫体上的分生孢子萌发形成芽管,24h后,在复眼、腹部气孔、足的基节和翅的基部等部位菌丝侵入黑刺粉虱体内,接种72h后虫体被厚厚的菌丝层覆盖。分生孢子可以直接以芽管侵入表皮,也可以产生附着胞再侵入。分生孢子在黑刺粉虱体表萌发形成芽管,芽管顶端可形成附着胞,附着胞再形成侵入钉穿透寄主体壁。寄主体表结构影响形成附着胞的形状及穿透体壁时芽管长度。穿刺点处的小孔及附着胞周围发现粘状分泌物,为蜡蚧轮枝菌在入侵黑刺粉虱过程中穿透体壁时对寄主表皮产生降解作用的酶。     

稻瘟菌侵染对水稻细胞骨架排列方式的影响

采用免疫荧光技术成功检测到水稻叶鞘内表皮细胞中微管和微丝的分布情况.稻瘟病菌的侵染使水稻叶鞘内表皮细胞中微管、微丝排列方式发生明显的改变,这种排列方式的改变非常灵敏,且在亲和性互作和非亲和性互作之间差异明显.非亲和性互作反应中,病菌侵染早期微管、微丝均放射状向病菌侵染点分布,至寄主细胞产生过敏性坏死时,逐渐受到破坏而降解.亲和性互作反应中,微管、微丝在病菌侵染的早期则已开始降解,形成短棒状或点状结构,比较均匀地分布于整个细胞,病原菌侵染菌丝在寄主细胞中扩展时,难以观察到完整的微管、微丝.     

关于大白菜—软腐欧文氏菌互作的某些新观点

以病菌根系侵入、系统性潜伏侵染为主要环节的病害循环;寄主—病菌接触识别;潜伏侵染和致病或发病状态转变中的寄主—病菌互作;互作的阶段性和专化性等,是近10年来对大白菜软腐病重新研究和认识的主要观点。这些观点对探讨和实施病害控制的新途径已产生重要的指导作用。     

植物类受体蛋白激酶的研究进展

植物类受体蛋白激酶是一类定位在质膜上,具有胞外结构域、跨膜结构域和胞内激酶域的蛋白质.简要介绍类受体蛋白激酶的结构、种类以及其在植物生长发育过程中的作用,并对近几年植物类受体蛋白激酶的研究进展进行了综述.     

植物菌根共生体结构的研究进展

对菌根共生体结构的研究近年受到重视,并从外部形态、组织解剖结构逐渐深入到超微结构方面。笔者从以下几方面对菌根结构的研究进行了综述:菌根的形态和类型多样,因真菌、植物种类及生长环境而有所差异;菌套、哈氏网的类型及外延菌丝的形态多样,在菌根共生体营养吸收和交换中发挥重要作用;在超微结构方面,菌根的形成对寄主质膜及细胞骨架结构有一定的影响;同时,共生体中真菌液泡系统形态结构变化也与营养储存和运输能力密切相关。对菌根共生体结构的研究有助于了解其与根功能的适应及深入探讨菌根的作用机理,为菌根菌的进一步应用提供理论基础。     

武夷山自然保护区经济植物病原真菌调查初报

<正> 我们自1979年6月——1980年底,先后四次深入崇安、建阳、光泽三县境内保护区所属十多个有代表性的地带,采集寄生性的植物病原真菌标本,侧重于经济植物病原真菌。我们在84种经济植物上,采得病原真菌117种,其中我省新记录44种,我国新记录3种。初步调查结果表明,保护区内真菌资源极为丰富,不但种类和数量繁多,而且拥有可供食用、药用以及促进植物生长或引起植物病害等多种类型的真菌。现将经鉴定巳知的经济植物病原真菌的种类记述于下。名录中的病原真菌,按真菌分类亚门归类,在亚门内依真菌学名的第一个字母顺序排列。每种病原真菌均列举其寄主及采集地点。国内新记录的病原真菌,在其学名前标以“△”,本省新记录的病原真菌,标以“§”号,以资区别。     

活性氧在植物-病原物相互作用过程中的作用

病原菌侵入植物后可诱导活性氧的爆发,并且在非寄主互作中比寄主互作中活性氧的积累更明显.活性氧的爆发已被认为是寄主防卫反应之一,在植物的抗病性中具有很重要的作用.本文介绍了植物与病原物相互作用过程中活性氧的类型、性质以及活性氧的产生机制和清除系统酶活性;重点讨论在植物与病原体相互关系中活性氧的可能作用,以及植物-病原物亲和性互作与非亲和性互作之间在这方面的差异.并对以上几个方面之间的关系进行了评述.     

细胞壁降解酶在植物病原黄单胞菌致病性中的作用研究进展

由Ⅱ型分泌系统(typeⅡsecretion system,T2SS)分泌的细胞壁降解酶(cell-wall degrading enzymes,CWDEs)在病原菌寄生与致病进程中起着重要作用.CWDEs在植物病原黄单胞菌中具有多样性与特异性.CWDEs在黄单胞菌与寄主植物互作中具有双重功能,一方面能降解植物细胞壁,引起植物病害;另一方面能诱导植物防卫反应.对植物病原黄单胞菌中已鉴定CWDEs的生物学特性及其在病原菌与寄主植物互作中的作用进行了总结,并就CWDEs在不同植物病原黄单胞菌中的差异性进行了分析,同时对未来植物病原黄单胞菌CWDEs的研究方向进行了展望,以期增进对黄单胞菌与寄主植物互作机理的理解.     

细胞色素P450表达在植物防御反应中的作用

细胞色素P450是广泛存在植物体中的一种多功能氧化酶,它在植物对病原侵袭的防御反应中起着重要的作用.本文从植物P450的多样性,及在寄主-病原物不亲和互作中的特异表达,证明了P450参与植物的抗病反应;同时,分析P450在植物抗病反应的作用途径,说明P450在植物抗病基因工程中存在巨大的应用潜力.     

我国用材林主要真菌病害致病机制及内生菌对病害的生防作用

我国人工林面积居世界首位,但木材人均消费量仅为发达国家的1/5,木材对外依存度接近50%。用材林对我国木材安全、生态安全、森林碳汇和绿色发展具有重要意义,但用材林树种单一、生物多样性水平较低,林分结构简单,生物灾害频发,其中真菌病害已成为我国用材林的主要生物灾害。笔者围绕我国用材林树种重要真菌病害的致病机制和绿色防控等科学问题,综述了我国主要用材林树种的重要真菌病害种类、危害特点、病原致病分子机制和内生菌防治病害等方面的研究进展,并对未来用材林重要真菌病害的流行监测、病原-寄主互作、病害的栽培管理与可持续绿色防控等综合防控策略等进行了展望。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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