小麦隐匿柄锈菌与小麦互作不同阶段的基因差异表达分析

[目的]小麦叶锈病是影响小麦生产主要病害之一,其病原菌新小种的出现和劣势小种上升为优势小种导致抗病品种的抗病性不断被克服.小麦隐匿柄锈菌与小麦互作不同阶段差异表达谱分析对于揭示该病菌致病的分子机制,进而有效防控小麦叶锈病具有重要意义.[方法]利用转录组分析小麦隐匿柄锈菌致病生理小种与感叶锈病小麦品种MuTcLr19亲和...     

应用环氧乙烷混合气进行土壤消毒的试验效果

土壤是病原菌生活、繁殖、休眠的重要场所,也是传染作物病害的重要途径。生产中,通常利用轮作更换病原菌寄主,控制病害发生。而在温室,大棚等活动积温较高的保护地环境,以及连作种植时,病原菌便得以大量繁殖,对作物危害日趋严重,造成减产甚至绝收。防治保护地病害多采用棚内熏蒸、叶面喷撒等用药方     

广州南沙番石榴枯萎病的病原菌

近年来,以枝条萎蔫、枝干干枯直至整株枯死为典型症状的番石榴枯萎病在广州南沙区严重发生。为明确该病害的病因,我们进行了病害调查、标本采集、病原菌分离和致病性测定;通过病原菌的显微形态比较和基于多基因系统发育分析,鉴定了病原菌种类;通过对寄主不同部位接种,测定了病原菌对寄主根、茎干和果的侵染能力。结果表明,引起广州南沙番石榴枯萎病的病原菌为番石榴纳氏霉Nalanthamala psidii,该菌不仅能从有伤的枝条侵染造成整株枯死,还能从根部侵染,使植株生长明显减缓,最终造成植株枯死,此外还可以侵染果实造成腐烂症状。本研究明确了广州南沙发生的番石榴枯萎病与中国台湾、马来西亚和南非报道的番石榴立枯病是一种病害,均是由番石榴纳氏霉侵染引起,为该病害的侵染特性及防控技术研究提供理论依据。     

间套作控制作物病害的机理研究进展

合理间套作是抑制植物病害流行的天然屏障,利用间套作持续控制作物病害是国内外近年来的研究热点。目前,有关间套作的研究主要集中在田间作物搭配模式、光热和养分资源高效利用、病害控制效果及产量优势等方面。然而,有关间套作控病机理尚缺乏系统总结。本文首先综述了间套作对气传病害和土传病害的控制效果;其次,从寄主作物抗性、病原菌和环境(土壤及田间小气候)三方面阐述间套作控制病害的机理,主要为:(1)合理间套作促进养分吸收利用,改善寄主作物的生理生化特性,进而提高寄主作物的抗病性;(2)间套作一方面增加地上部作物多样性,形成物理屏障阻挡病原菌的传播,另一方面增加地下部根系分泌物的多样性,对病原菌进行化感抑制,降低病原菌的存活与侵染;(3)间套作改变田间小气候(田间湿度、温度和通风等)及土壤微生态环境(微生物区系、群落结构和土壤酶活性)而增强间套作的控病效果。最后,讨论了当前间套作与病害控制研究方法的局限性,并展望了间套作控制病害的未来研究方向。     

吉林省香菜一新病害——白粉病

通过病害症状和病原形态学特征对吉林省香菜种植区白粉病病原菌进行鉴定,结果为该病由独活白粉菌（Erysiphe heraclei DC．）引起。香菜白粉病为吉林省香菜一新病害,且芫荽属为东北地区白粉菌属级新记录寄主。     

小麦品种莱州137抗叶锈病鉴定及基因检测

叶锈病是小麦生产中的重要病害,培育持久抗性品种可以有效控制该病害。本研究以抗病品种莱州137、感病对照品种郑州5389、慢锈性品种SAAR以及36个已知抗叶锈病基因的载体品种为材料,在苗期和成株期进行了2年2点的接种鉴定,通过系谱分析、基因推导和12个与抗叶锈病基因连锁的分子标记检测,发现莱州137携带Lr26、Lr10、Lr14b以及其他未知抗叶锈病基因,且表现成株抗性的特点,说明其可能含有未知的成株抗性基因,可作为新的小麦抗叶锈病抗源加以利用。     

玉米瘤黑粉菌的寄生策略及其调控机制

玉米瘤黑粉病是由担子菌Ustilago maydis对玉米的活体寄生所引起的真菌病害。该病原菌为双相型真菌,需要寄生于玉米植株来完成其有性生殖过程。综合相关研究报道,本文把U.maydis对寄主植物的寄生过程划分为7个阶段,包括形成致病性双核菌丝体、附着寄主植物表面、穿透寄主表皮、消减寄主防御反应、在寄主体内菌丝增殖、使寄主瘤变和生成厚垣孢子等。围绕寄生进程特点和关键基因,分别阐述了各个阶段的相关调控机制以及对寄主植物的致病性;展现了U.maydis为达到有性生殖目的而实施步步为营的寄生策略。本文对U.maydis寄生过程的阶段划分,有助于人们深入了解U.maydis与寄主植物之间互作机制、提供相关病害防控新思路。     

苹果链格孢菌与寄主叶片互作的超微结构研究

以苹果杂交组合(‘华脆’ב金冠’)F1代杂种实生苗群体易感病株系为材料,通过扫描电镜、透射电镜等观察方法,对苹果链格孢菌与寄主叶片互作过程进行了细胞学观察,分析苹果链格孢菌侵染寄主的动态过程和变化规律,以揭示苹果病害发生机制。结果表明,苹果链格孢菌侵染寄主叶片时,多数在表皮分枝扩展,很少通过气孔器或其他方式入侵细胞内部。互作后期,寄主叶细胞内叶绿体和质膜变化显著,多数细胞器降解,表明病原菌已分泌AM毒素作用于寄主。     

辽宁省水稻病害调查研究

这份调查研究,经1954年至近年,逐步采集和鉴定了辽宁省水稻病害约30余种。鉴定后绘制病原菌原图,并对每种病害的症状特点、病原菌、发生分布、防治要点等做扼要附述。以便对我省水稻病害有一概括的了解,和水稻病害诊断鉴定的参考。     

大豆疫霉与大豆互作中的识别与反识别

大豆疫霉引起的大豆疫病是大豆生产上的毁灭性病害。深入了解大豆疫霉与寄主在分子层面的互作机制是解析病原菌致病机理、针对性地制定防治措施的必要前提。目前研究表明,植物通过两个层面的识别机制来启动防卫反应,而能否正确识别"非我"分子则是植物开启免疫系统的关键。而对于病原菌,则采用多种分子策略来极力逃避寄主的识别机制,分泌效应分子协同抑制寄主免疫反应。本文综述了一系列大豆抗病基因介导的小种专化抗性丧失的原因,以及大豆疫霉效应分子逃避和破坏寄主免疫反应的分子策略,并讨论了基于这些分子互作机制应用于筛选新型抗病资源和精确育种的可能性。     

杨树抗锈性研究现状

综述了落叶松一杨栅锈菌生理小种分化、寄主杨树抗锈性、抗锈病基因分子标记和抗病基因连锁遗传图谱构建技术;分析了我国杨树抗锈病育种研究的现状和亟待解决的问题。     

松杨栅锈菌遗传多样性初步分析

采用ITS-nrDNA-RELP、测序技术、RAPD(随机扩增多态性DNA)分子标记技术,对我国松杨栅锈菌不同地域的5个生理小种11个菌系进行了遗传多样性分化研究.结果表明,该菌在我国的遗传分化与地理来源相关,可分为西部地理群和北方地理群.西部地理群又可分为高山森林生态型(HMF)和平原生态型(WPL).小种遗传分化不一定与致病性分化一致.t检验表明,各生理小种RAPD遗传多样性指数无明显差异,高山森林小种遗传多样性指数(0.5172)略高于平原小种遗传多样性指数(0.5089).核糖体基因转录间隔区高度保守,不适合该菌种内群体遗传多样性分化研究.     

落叶松-杨栅锈菌基因复制事件及共线性分析

落叶松-杨栅锈菌是一种分布广且危害严重的林木病原真菌.了解基因组内发生的基因复制事件及基因组间的共线性关系,能为最终理解落叶松-杨栅锈菌适应性进化等生物学问题提供帮助.落叶松-杨栅锈菌全基因组水平上基因复制相关研究未见报道,共线性研究报道也较少.本研究利用落叶松-杨栅锈菌全基因组序列分析其基因复制模式.结果表明,落叶松...     

Molecular Genetics of Rust Resistance in Poplars (Melampsora Larici-Populina Kleb/Populus Sp.) by Bulked Segregant Analysis in a 2 X 2 Factorial Mating Design

With random amplified polymorphic DNA (RAPD) markers, we have tagged a genomic region in Populus sp. involved in qualitative resistance to Melampsora larici-populina. Our approach was based on three steps: use of RAPD markers that can be quickly and efficiently researched; application of ``bulked segregant analysis' technique on individuals of one interspecific family P. trichocarpa X P. deltoides to search for RAPD markers linked to resistance; and validation of these markers in two other families linked with the first one in a 2 X 2 factorial mating design. Of five detected markers, only one marker M03/04_480 was polymorphic in the three segregating families, involving 89 individuals and four different parents. We have estimated the recombination value of 1 cM with 1 cM sampling error.     

Genetic architecture of qualitative and quantitative Melampsora larici-populina leaf rust resistance in hybrid poplar: genetic mapping and QTL detection

In order to elucidate the genetic control of resistance to Melampsora larici-populina leaf rust in hybrid poplars, a Populus deltoides x P. trichocarpa F(1) progeny was analysed for qualitative and quantitative rust resistances. This progeny was evaluated for three components of quantitative resistance (latent period, uredinia number and uredinia size) to seven M. larici-populina strains in controlled conditions, and for one component of field susceptibility (rust colonization on the most infected leaf). One qualitative resistance locus inherited from P. deltoides, R(1), was localized on the genetic map. It segregates 1 : 1 in the F(1) progeny and is effective against four of the studied strains. QTL analysis was performed separately on R(1) and r(1) genotype subsets. An additional detection was conducted on the entire F(1) progeny for the three strains able to overcome R(1) and for MAX2. A total of nine QTLs were detected. Two had large, broad-spectrum effects. One (R(US)) is inherited from the P. trichocarpa parent; the other is inherited from P. deltoides and colocalized with R(1). Seven QTLs had only limited and specific effects. Significant interaction effects were detected mainly between the two major QTLs. Implications of these results for durable resistance breeding strategies, and possible benefits from the Populus genome sequence, are discussed.     

Temperature-Light Intensity Effect on the Antagonism of Species of Cladosporium to Melampsora larici-populina on Cultivars of Populus X euramericana (Dode) Guinier

The antagonistic and colonistic effect of post-inoculation temperature and light intensity was investigated in a factorial experiment involving four Cladosporium spp., three poplar cultivars, two levels of temperature and light intensity, anda race of Melampsora larici-populina. The species of Cladosporium were more antagonistic to uredinial production on the inoculated leaf discs of the cultivars when these were incubated in high temperature – high light intensity than in any other regime. Whilst colonisation of the uredinia was usually minimal in discs incubated on the high temperature – high light intensity regime, the condition of incubation favouring maximum colonisation varied with the cultivar and the species of Cladosporium employed. All the major factors and most of their two-, three- and four-way interactions were significant determinants of variation in both antagonism to uredinial production and in colonisation of the uredinia produced. The validity ofextrapolation from such experiments to the field environment is discussed.