小麦叶锈菌休眠与萌发夏孢子的差异表达

【目的】小麦叶锈菌引起的小麦叶锈病是小麦的重要病害之一,孢子萌发和侵入气孔是保证叶锈菌正常侵染寄主的重要前提。本研究旨在研究小麦叶锈菌夏孢子萌发的差异表达特性,为揭示萌发的机制及其与致病的关系提供依据。【方法】利用小麦叶锈菌致病类型THTT的休眠夏孢子和萌发夏孢子进行RNA-seq分析。【结果】在萌发夏孢子中筛选出相比休眠夏孢子上调表达的基因为4400个,下调基因5325个。GO富集分析发现,上调差异基因主要涉及细胞进程、有机物代谢、信号传导、单个有机体过程、催化酶活性等;下调基因主要涉及单组织过程、单个有机体细胞过程、有机物代谢过程、催化活性调节等过程。利用KEGG分析发现,差异基因共参与109条通路,从中筛选出两条与孢子萌发相关的通路——丝裂原活化蛋白激酶(MAPK)信号通路和囊泡运输中的SNARE蛋白交流。10个基因的定量分析结果与基因数字表达谱分析结果一致。【结论】研究获得了叶锈菌孢子萌发及侵入气孔过程中的重要差异基因,研究结果为研究叶锈菌致病机制奠定基础。     

隐匿柄锈菌(小麦叶锈病菌)UP-PCR遗传多样性分析

小麦叶锈病是世界麦区普遍发生的病害。以2008年采集于河北省的29个隐匿柄锈菌(小麦叶锈病菌)单孢子堆分离菌系为试验材料,利用39个小麦抗叶锈近等(单)基因系和7个UP-PCR(Universally Primed PCR)引物对其进行毒性多态性和分子多态性分析。7个UP-PCR引物共检测出48条条带,其中多态性条带41条,多态性百分率为85.42%,表明UP-PCR在隐匿柄锈菌中扩增多态性较高;经聚类分析,遗传相似系数为0.69–0.90,在相似系数0.72处,29个叶锈菌株聚为6组,体现了隐匿柄锈菌菌株间的亲缘关系和差异性,表明UP-PCR技术可用于小麦叶锈病菌群体遗传多样性研究。在物种水平上,隐匿柄锈菌观察等位基因数(Na)为1.85,有效等位基因数(Ne)为1.29,Nei’s基因多样性指数(H)为0.19,Shannon信息指数(I)为0.31,多态位点百分率(P)为85.42%,表明隐匿柄锈菌遗传多样性丰富,其中沧州的群体遗传多样性水平最高,群体内多样性大于群体间多样性。聚类分析表明沧州和石家庄的病菌群体亲缘关系最近,邢台与石家庄的群体亲缘关系最远。隐匿柄锈菌UP-PCR多态性与毒性多态性间无明显相关性,且两者均与地理来源无相关性。     

青藏高原东缘的锈菌资料Ⅲ.禾本科植物柄锈菌补记

本文报告采自云南及青海的四种禾本科植物柄锈菌。其中鹅冠草Roegneria kamojiOhwi上的鹅冠草柄锈菌Puccinia roegneriae J.-y. Zhuang & S.-x. Wei为新种。纤毛鹅冠草Roegneria ciliaris(Trin.) Nevski上的日本猬草柄锈菌Puccinia asperellae-japonicae Hara,弓果黍Cyrtococcum patens(L.) A. Camus上的东方柄锈菌Puccinia orientalis(H.Syd., P. Syd. & Butl.) Arth. & Cumm.以及乱子草Muhlenbergia hugelii Trin.上的乱子草柄锈菌Puccinia schedonnardi Kell. & Swing.为我国新记录种。对新种作了拉丁文描述。对其余的三个新记录种都作了讨论。本研究引用的中国标本(包括新种的模式)保存在中国科学院微生物研究所真菌标本室。     

铁线莲上隐匿柄锈菌性孢子器和锈孢子器发育的组织学和细胞学观察

通过光学显微镜技术和电镜技术对铁线莲上隐匿柄锈菌Puccinia recondita性孢子器和锈孢子器发育进行了组织学和超微结构的观察。观察表明,铁线莲上隐匿柄锈菌性孢子器呈瓶状,内生有大量单核的性孢子梗和侧丝。性孢子梗顶端产生大量的性孢子,每形成一个性孢子后,都在性孢子梗上留下一环痕。性孢子长椭圆形,表面无特殊纹饰。铁线莲上隐匿柄锈菌锈孢子器呈杯状,其内生长大量平行排列的长形双核锈孢子梗,每个锈孢子梗由上向下连续产生多个锈孢子。锈孢子梗通过产生隔膜先形成锈孢子原体,再分隔形成锈孢子和间生细胞。随着锈孢子的进一步发育,间生细胞解体,锈孢子彼此分开。成熟的锈孢子表面产生有密集的瘤状结构。     

青藏高原东缘的锈菌资料VI．柄锈菌属二新种

采自四川西部的二个柄锈菌新种,即寄生在小檗属Berberis sp．上的岷山柄锈菌Puccinia minshanensis J.Y. Zhuang ＆ S．X．Wei和寄生在大箭竹Sinarundinaria chungii(Keng) Keng f.上的箭竹生柄锈菌Puccinia sinarundinariicola J.Y. Zhuang & S.X. Wei. 文中对新种进行了拉丁文描述并作了简要讨论,附有显微照片和线条图。标本保藏在中国科学院微生物研究所菌物标本馆(HMAS)。     

伞形科植物上的柄锈菌属新种

本文报告了伞形科植物上三个柄锈菌属新种,它们是辽藁本Ligusticum jeholense Nakai & Kitagawa上的辽藁本柄锈菌Puccinia ligustici-jeholensis J.Y. Zhuang & S.X. Wei ,波棱滇芎Physospermopsis obtusiuscula (C.B. Clarke) Norman上的滇芎柄锈菌 Puccinia physospermopsis J.Y. Zhuang & S.X. Wei和蛇床 Cnidium monnieri (L.) Cusson上的天山柄锈菌 Puccinia tianshanica J.Y.Zhuang & S.X. Wei。对它们作了拉丁文描述并附简要讨论。模式标本保藏在中国科学院菌物标本馆(HMAS)。     

青藏高原东缘的锈菌资料Ⅵ.柄锈菌属二新种(英文)

采自四川西部的二个柄锈菌新种,即寄生在小檗属Berberissp．上的岷山柄锈菌PucciniaminshanensisJ．Y．Zhuap＆S．X．Wei和寄生在大箭竹Sinarundinariachungii（Keng）Kengf．上的箭竹生柄锈菌PucciniasinarundinarilcolaJ．Y．Zhuang＆S．X．Wei。文中对新种进行了拉丁文描述并作了简要讨论,附有显微照片和线条图。标本保藏在中国科学院微生物研究所菌物标本馆（HMAS）。     

青藏高原东缘的锈菌资料V.苔草属和姜属植物柄锈菌的增补

本文报告采自四川西部的三种柄锈菌新记录.它们是披针苔草Carex lanceolata Boott上的栗褐苔草柄锈菌Puccinia caricis-brunneae Dietel,苔草Carex sp.上的小堆柄锈菌Pucciniamicrosora Koernicke ex Fuckel以及阳荷Zingiber strialatum Dicls上的姜黄柄锈菌Puccinia curcumae T.S. Ramakrishnan & Sundaram。每个种有简要讨论并附线条图.标本保藏在中国科学院微生物研究所真菌标本室(HMAS)。     

青藏高原东缘的锈菌资料I.竹上的柄锈菌一新种

描述了采自四川西部山区竹上的柄锈菌一新种,即寄生在箭竹Sinarundinaria nitida(Mitf.) Nakai上的箭竹柄锈菌Puccinia sinarundinariae J-y. Zhuang & S.-x. Wei。模式标本保藏在中国科学院微生物研究所真菌标本室。     

小麦锈菌碳水化合物酶类基因家族的鉴定与进化分析

本研究利用已测序的条形柄锈菌Puccinia striiformis f.sp.tritici基因组序列信息,结合已公布的隐匿柄锈菌Puccinia recondita f.sp.tritici和禾柄锈菌Puccinia graminis f.sp.tritici全基因组编码蛋白序列,运用生物信息数据库和分析软件对其碳水化合物酶类(CAZymes)基因家族进行了注释和比较分析。结果表明,3种小麦锈菌共包含1 232个CAZymes编码基因(含有1 279个模块)。其中,条形柄锈菌具有明显较大的CAZymes家族,3种锈菌的CAZymes具有136个同源基因;相对于隐匿柄锈菌和禾柄锈菌,条形柄锈菌的GH、GT和AA家族发生显著扩增,而3种锈菌的PL家族并无差异;CBM家族则表现为由禾柄锈菌、隐匿柄锈菌到条形柄锈菌的递增式扩增。通过CAZymes、细胞壁降解酶、分泌蛋白、PHI、保守基序等不同形式注释的比较分析表明,对该基因家族而言,条形柄锈菌相对于隐匿柄锈菌和禾柄锈菌呈扩增现象,隐匿柄锈菌和禾柄锈菌的家族缩减水平存在差异。小麦锈菌CAZymes家族整体呈现的不同形式扩增或缩减现象,可能反映了锈菌与寄主长期协同进化过程中的寄生适应性需求,进而反映了其致病性演化机理。本研究结果有助于进一步全面认识小麦锈菌CAZymes基因家族进化在锈菌致病性变异中的作用,为揭示锈菌致病分子机制提供理论基础。     

Intercellular chitinase and peroxidase activities associated with resistance conferred by geneLr35to leaf rust of wheat

The effect of leaf rust (Puccinia triticina) infection on intercellular chitinase (EC 3.2.1.14) and peroxidase (EC 1.11.1.7) activities was studied in resistant [RL 6082 (Thatcher/Lr35)] and susceptible (Thatcher) near isogenic wheat (Triticum aestivum L.) lines at seedling, stem elongation and flag leaf stages of plant growth. The levels of activity of these enzymes were low during the seedling and stem elongation stages. Resistant plants at the flag leaf stage, during which the Lr35 resistance gene was maximally expressed, exhibited high constitutive levels of chitinase and peroxidase activities, in contrast to the lower constitutive levels of susceptible plants. The results suggest that chitinase and peroxidase, constitutively present in the intercellular spaces of Thatcher/Lr35 wheat leaves, may play a role in Lr35 mediated resistance to leaf rust.     

Molecular markers for wheat leaf rust resistance gene Lr41

Leaf rust, caused by Puccinia triticina Eriks., is an important foliar disease of common wheat (Triticum aestivum L.) worldwide. Pyramiding several major rust-resistance genes into one adapted cultivar is one strategy for obtaining more durable resistance. Molecular markers linked to these genes are essential tools for gene pyramiding. The rust-resistance gene Lr41 from T. tauschii has been introgressed into chromosome 2D of several wheat cultivars that are currently under commercial production. To discover molecular markers closely linked to Lr41, a set of near-isogenic lines (NILs) of the hard winter wheat cultivar Century were developed through backcrossing. A population of 95 BC₃F_2:6 NILs were evaluated for leaf rust resistance at both seedling and adult plant stages and analyzed with simple sequence repeat (SSR) markers using bulked segregant analysis. Four markers closely linked to Lr41 were identified on chromosome 2DS; the closest marker, Xbarc124, was about 1 cM from Lr41. Physical mapping using Chinese Spring nullitetrasomic and ditelosomic genetic stocks confirmed that markers linked to Lr41 were on chromosome arm 2DS. Marker analysis in a diverse set of wheat germplasm indicated that primers BARC124, GWM210, and GDM35 amplified polymorphic bands between most resistant and susceptible accessions and can be used for marker-assisted selection in breeding programs.     

Microsatellite tagging of the leaf rust resistance gene <Emphasis Type="Italic">Lr16</Emphasis> on wheat chromosome 2BSc

Leaf rust, caused by Puccinia triticina, is one of the most damaging diseases of wheat worldwide. Lr16 is a widely deployed leaf rust resistance gene effective at the seedling stage. Although virulence to Lr16 exists in the Canadian P. triticina population, Lr16 provides a level of partial resistance in the field. The primary objective of this study was to identify markers linked to Lr16 that are suitable for marker-assisted selection (MAS). Lr16 was tagged with microsatellite markers on the distal end of chromosome 2BS in three mapping populations. Seven microsatellite loci mapped within 10 cM of Lr16, with the map distances varying among populations. Xwmc764 was the closest microsatellite locus to Lr16, and mapped 1, 9, and 3 cM away in the RL4452/AC Domain, BW278/AC Foremost, and HY644/McKenzie mapping populations, respectively. Lr16 was the terminal locus mapped in all three populations. Xwmc764, Xgwm210, and Xwmc661 were the most suitable markers for selection of Lr16 because they had simple PCR profiles, numerous alleles, high polymorphism information content (PIC), and were tightly linked to Lr16. Twenty-eight spring wheat lines were evaluated for leaf rust reaction with the P. triticina virulence phenotypes MBDS, MBRJ, and MGBJ, and analyzed with five microsatellite markers tightly linked to Lr16. There was good agreement between leaf rust infection type (IT) data and the microsatellite allele data. Microsatellite markers were useful for postulating Lr16 in wheat lines with multiple leaf rust resistance genes.     

广叶绣球菌不同生长阶段栽培基质中代谢物差异分析

【背景】栽培基质的利用是广叶绣球菌(Sparassis latifolia)栽培中重要的生理过程,但栽培过程中基质代谢物的变化尚不清楚。【目的】通过不同生长阶段栽培基质中差异代谢物分析挖掘关键代谢物,为广叶绣球菌基质利用机理研究提供理论参考。【方法】利用UHPLC-MS/MS技术分析广叶绣球菌菌丝(Myc)、原基(Pri)和子实体(FB)生长阶段栽培基质中代谢产物的变化,通过不同数据库进行代谢物注释并进行KEGG通路富集分析。利用LC-MS/MS技术检测不同发育阶段绣球菌中植物类激素含量。【结果】三个不同栽培阶段基质中共鉴定出代谢产物1 360个。不同比较组(Pri vs. Myc、FB vs. Myc和FB vs. Pri)间共有的差异代谢产物179个,含量最高的50个代谢物主要包括氨基酸、脂质、吡喃酸、吡喃酮和植物类激素等物质。其中氨基酸含量在Myc、Pri和FB阶段基质中逐渐降低,而吡喃酸和吡喃酮类化合物含量逐渐升高。植物类激素中的赤霉素在Pri和FB阶段基质中含量较高,茉莉酸在Myc阶段基质中含量较高。对不同发育阶段绣球菌植物类激素进行检测,发现赤霉素GA7仅在原基中检测到,1...     

西瓜食酸菌与黄瓜互作转录组分析

【背景】细菌性果斑病是一种严重的种传细菌病害,其病原菌为西瓜食酸菌。截至目前对该病病原菌与寄主的互作机制认识极为有限。葫芦科的模式植物黄瓜易被西瓜食酸菌侵染发病,对西瓜食酸菌-黄瓜互作体系进行转录组分析,可以为探究西瓜食酸菌与寄主互作机制奠定重要基础。【目的】解析西瓜食酸菌-黄瓜互作时的相互响应规律。【方法】以细菌悬液注射接种6d黄瓜子叶,处理48 h的子叶作为转录组测序样本。利用RNA-Seq技术分析西瓜食酸菌FC440菌株与黄瓜9930品种互作时基因的表达特征。【结果】测序数据质量分析发现,各样品不同重复间相关性较强,与参考基因组比对率达95%以上,聚类分析发现对照组与处理组表达模式相反,样品处理达到一定效果,表明数据整体质量较高。选取6个差异表达基因进行RT-qPCR验证,结果显示6个基因的表达模式与转录组结果基本一致,表明转录组测序结果比较可靠。西瓜食酸菌和黄瓜互作48 h后,在转录组水平分别检测到1 618个和8 698个差异表达基因。Gene Ontology (GO)功能注释显示,细菌的差异基因显著富集在细胞组分中的细胞膜(37.5%)和膜部分(27.0%),生物过程中的氧化还原过程(66.7%)以及分子功能中的水解酶活性(66.5%);黄瓜的差异基因显著富集在细胞组分中的质体(22.2%)和叶绿体(21.3%),分子功能中的催化活性(70.0%)以及生物过程中的碳水化合物衍生物代谢(32.2%)。Kyoto Encyclopedia of Genes and Genomes (KEGG)分析显示,细菌中致病相关基因显著富集在群体感应及细菌趋化性途径,而且群体感应系统基因下调更显著。黄瓜中调控钙依赖蛋白激酶(Calcium-Dependent Protein Kinase,CDPK)、钙调素和类钙调素(Calmodulin and Calmodulin-Like,CaMCML)及呼吸氧暴发激酶(Respiratory Burst Oxidase Homologne,Rboh)的基因总体上调,调控苯丙氨酸裂解酶(Phenylalanine Ammonia-Lyase,PAL)的基因和谷胱甘肽S-转移酶(Glutathione S-Transferase,GST)的基因在相应代谢途径中数量最多且上调程度明显。【结论】获得较高质量的西瓜食酸菌与黄瓜互作的转录组测序结果。群体感应与西瓜食酸菌FC440菌株致病力密切相关;寄主黄瓜应对西瓜食酸菌侵染以Ca~(2+)信号激活的防御反应为主。PAL和GST在黄瓜抵抗西瓜食酸菌侵染中发挥重要作用。本研究为进一步深入解析西瓜食酸菌与寄主互作的机制奠定了基础。     

Effect of gene Lr34 in the enhancement of resistance to leaf rust of wheat

Summary Leaf rust resistance gene Lr34 is present in many wheat cultivars throughout the world that have shown durable resistance to leaf rust. Fourteen pair-wise combinations of Lr34 and seedling leaf rust resistance genes were developed by intercrossing near isogenic Thatcher lines. In both seedling and adult plant tests homozygous paired combinations of specific resistance genes with Lr34 had enhanced resistance relative to either parent to different numbers of isolates that were avirulent to the additional resistance genes. The TcLr34, 18 line also expressed enhanced resistance to specific isolates virulent to Lr18 in seedling and adult plant stages. In rust nursery tests, homozygous lines were more resistant than either parent, if the additional leaf rust gene conditioned an effective of resistance when present singly. The ability of Lr34 to interact with other genes conditioning effective resistance may contribute to the durability of leaf rust resistance in cultivars with Lr34. Contribution 1453 Agriculture Canada