植物微生物学课件.ppt

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1、真菌界,植物微生物学第四讲,Eumycotan Fungi真菌界,Unlike chromistan fungi-most have no motile stages so best adapted to landPhylum Chytridiomycota（壶菌门）exception-do have flagellae-1 posterior whiplash,Phylum Zygomycota（接合菌门）most have coenocytic hyphae(ie no septae)Phylum-Dikaryomycota（双核菌门）septate hyphae.Largest and

2、most important group.,真菌界一般性状,By far the largest group of fungi:over 100,000 sp knownprobably well over 1,000,000 exist!many capable of digesting very complex substances(cellulose,lignin，chitin)-due to extracellular enzymes（胞外酶）hyphae（菌丝）can penetrate into solid masses e.g wood and decompose it rapi

3、dlyproduce vast numbers of spores so capable of spreading rapidly.（产孢繁殖）,Phylum Chytridiomycota壶菌门,mostly live in water or soil-decomposerssingle cell or hyphae,营养体为简单细胞或菌丝sometimes develop rhizoids（根状体）often parasiticSynchytrium（集壶菌属）causes wart disease of potatoes（马铃薯癌肿病）,Chytrid fungi on decaying

4、 leaf in river This type is eucarpic（分体产果）having separate rhizoids and reproductive parts.Others are holocarpic（整体产果）-only have reprod.parts,Potato wart diseaseSynchytrium endobioticum severe effect on yield resistant varieties available-but new virulent strains of fungus arising warts contain spora

5、ngia which release zoospores-infect new potatoes-cause rapid cell division=wart,马铃薯癌肿病症状,接合菌门主要特征,wide,thin-walled multinucleate coenocytic hyphae粗大的薄壁多核无隔菌丝limited ability to digest complex substratessexual spore=a thick walled zygosporangium（接合孢子）-germinates by meiosis to form new hyphae.,Phylum Z

6、ygomycota,Phylum Zygomycota接合菌门,class Zygomycetes 接合菌纲Mucorales毛霉目 腐生-saprobic(eg bread moulds)common saprophytes-but limited ability to degrade complex compounds compared to Dikaryomycota Life cycle-see Rhizopus stolonifer(Fig 3.5)class Trichomycetes 毛菌纲-parasites of arthropods 节肢动物的寄生物,Eumycotan F

7、ungi,Bread Mould-Rhizopus stolonifer面包霉,Life cycle of Rhizopus stolonifera,根霉生活史,Mucor-Life Cycle,Sexual stages-teleomorph,Asexual stages-anamorph,毛霉生活史,Zygospore of Rhizopus(diploid-will go through meiosis),Teleomorphs in Zygomycetes,接合孢子,Sporangium in Rhizopus,sporangiophore,Sporangium containing

8、many sporangiospores(asexual)孢子囊内含许多孢囊孢子（无性的）,ANAMORPHS IN ZYGOMYCETES,无性孢子（孢囊孢子）,Anamorphs in Zygomycetes,无性阶段,双核菌门-子囊菌亚门,Chromistan FungiEumycotan Fungi.1.Chytridiomycota2.Zygomycota3.Dikaryomycota,AscomycotinaBasidiomycotina,phylasub-phyla,Dikaryomycota子囊菌亚门,Compared to Zygomycota:-1.have thinner

9、 hyphae菌丝细-thicker walls 壁厚 divided into compartments by 有隔 septae which contain pores.隔板有孔2.This makes them tougher and much more able to thrive in drier situations更耐干旱3.More capable of utilizing complex substances-e.g cellulose.,lignin,keratin,chitin.4.Many important pathogens of plants,Dikaryomyc

10、ota二核菌门,5.Very important in mycorrhizal菌根 associations 6.Many species have developed an association with algae to form lichens地衣.7.Hyphae can fuse and exchange nuclei and form heterokaryons异核体,particularly dikaryons 二核体-necessary stage to sexual reproduction.Dikaryon=cells have 2 haploid nuclei of d

11、ifferent origins in a stable state-continued on each cell division,Ascomycotina-main features(cf.Basidiomycotina)担子菌主要特征,restricted dikaryophase(only in special fruiting bodies-ascoma)二核阶段不长（与担子菌比）Many cells within the ascoma develop into asci.Nuclear fusion and meiosis occurs to form 4,8,16 etc asc

12、ospores子囊孢子 inside each ascus子囊.simple septal pores2-layered cell walls双层壁no clamp connections无锁状结构molecular differences from Basidiomycotina(GC content etc.),many pathogenic fungi 许多是病原菌eg humans(ringworm,athletes foot-attack keratin)如足癣plants-southern corn blight,powdery mildews玉米小斑病和白粉病rots and m

13、oulds of wood and cotton etc木材和棉花霉烂producers of mycotoxins(eg aflatoxin)产毒素如黄曲霉beneficial decomposers of material in soils 土中的分解者insect and nematode predators and parasites昆虫和线虫的捕食者和寄生物useful in food(yeast,cheeses)or antibiotic prep.(penicillin,cyclosporine)用于食品（酵母和奶酪）或生产抗生素important in molecular an

14、d classical genetics分子和经典遗传学的模式生物。,Taphrina deformans-peach leaf curlClaviceps purpurea-ergot of Ryecaused outbreaks of St Anthonys Fire in Middle Ages.Source of LSD,毒麦和桃缩叶病,Highly prized edible Morels,高价值的食用菌,引起植物病害,Ascomycotina-main groups分纲,Class-Ascomycetes 子囊菌纲filamentous species丝状菌Class-Saccha

15、romycetes 酵母纲 unicellular yeast species单细胞的菌Class Deuteromycetes-半知菌“纲”catchall group for species without sexual stagesmost Lichen fungi are Ascomycetes大多数地衣真菌是子囊菌纲,Holomorph=Anamorph+Teleomorph生活史分无性阶段和有性阶段,Anamorph=asexual stages-mitosis-usually haploid无性阶段，有丝分裂，通常是单倍体Teleomorph=sexual stages-invo

16、lves dikaryons,diploidy and meiosis有性阶段，涉及二核阶段、二倍体阶段和减数分裂三个阶段,Teleomorphs of Ascomycetes子囊菌有性阶段,Teleomorph begins when hyphae anastomose(=fuse together),become dikaryotic and aggregate into compact masses(ascoma).有性阶段始于菌丝融合时，变成二核体，聚集成紧密的一团。,4 kinds of ascoma4种子囊果,apothecia-open cups子囊盘，开放的杯状物perithe

17、cia+pseudothecia-narrow opening flasks子囊壳+假囊壳-小口烧瓶状cleistothecia-closed spheres or flasks.闭囊壳-封闭的瓶状物或烧瓶状物,4.cleistothecium,2.perithecium,3.pseudothecium,Types of ascoma子囊果的类型,1.Apothecium,子囊盘,Life cycle of typical Ascomycete,Life cycle of typical Ascomycete典型子囊菌的生活史,Ascomycetes,Basidiomycetes,ascus,

18、basidium,clamp connection every time a hyphal cell divides,crozier only found just before ascus formation,子囊菌有性生殖（上）和担子菌（下）有性生殖的比较（钓状体和锁状联合）,bitunicate ascus双层壁的子囊,unitunicate 单层壁inoperculate无孔口,unitunicate 单层壁operculate ascus有孔口,原囊态的子囊,The 4 main types of asci子囊的4种主要形态,In Ascomycetes,anamorphs and

19、teleomorphs often develop at different times and places.Each stage is therefore often collected in ignorance of the existence of the otherNormal classification is based on telomorph stages,but mycologists have had to classify specimens in which they only find anamorph stages.Thus parallel systems of

20、 nomenclature have sprung up-we have teleomorph genera and anamorph genera and mycologists try to draw connections between them where possible.DNA analyses will make this much easier in future.有性和无性阶段在不同时间和地点发生，采集到的标本或是有性或是无性态，正常的分类 是根据有性态，但有些菌只发现了无性态，只好根据无性态分类。因而有两个并行的命名体系。菌物学家试图找到两者间的联系。将来DNA分析技术将

21、使得更容易。,The anamorph-teleomorph probleme 有性和无性阶段问题,In some cases it has been possible to connect the anamorph name with the teleomorph name-but in many others this has not yet been done and may never be possible because the organism may have lost the ability to reproduce sexually.Of 30,000 known Asco

22、mycetes only 5,000 have been connected to their anamorphs-results often messyeg teleomorph genera,Nectria and Gibberella,both have anamorphs which have been classified in the anamorph genus FusariumMany anamorphs(85%)have no known teleomorph-are termed Deuteromycetes.有时将有性与无性联系容易，许多情况下难甚至做不到，因为有的菌丧失

23、了有性生殖的能力。30 000种已知的子囊菌只有5 000种与无性态挂上了勾，结果往往是杂乱的，如有性阶段的丛剌壳属和赤霉属的无性阶段都是镰霉属。许多（85%）无性态已知但不知有性态，归到半知菌纲。,Recombination during MITOSIS has been observed in many fungi-it may be particularly well developed in Deuteromycetes减数分裂时发生重组已在许多真菌中发现，但半知菌尤多。两个不同核的细胞偶尔融合成为双核细胞，通过核融而成体细胞二倍体，有丝分裂时发生交换而分离或丢失染色体成单倍体。,Pa

24、rasexual cycle 准性循环,The anamorph 无性阶段,The typical anamorph spore in Ascomycetes=conidia produced outside a specialized hyphal cell.典型无性孢子是分生孢子，外生于特殊菌丝细胞。compare with Zygomycetes which produce sporangiospores inside a sporangium.而接合菌的无性孢子是在孢子囊内产生孢囊孢子。conidia=asexual spores produced in vast numbers by

25、 mitotic divisions分生孢子是通过有丝分裂大量产生的无性孢子,classification of ascomycete anamorphs based on 子囊菌无性态分类依据是,conidial features分生孢子特征Hyphomycetes丝孢纲-conidiophores never enclosed分生孢子梗 生Coelomycetes 腔孢纲-conidiophores enclosed in a covering.分生孢子梗被封闭conidial shape and septation important孢子形态和分隔数是重要依据conidiophore d

26、etails also used分生孢子梗的细节也用于分类,Coelomycetes have their conidia in a covered structure.Covered either by host cells(acervulus分生孢子盘)or by fungal hyphae in flask shape(pycnidium分生孢子器),acervulus,pycnidium,conidium,分生孢子器（右）和分生孢子盘（左）,conidium,分生孢子梗的类型单梗、分支、束生、座状,Conidia of 孢子Aspergillus sp.,Conidiophore孢子梗

27、,曲霉菌分生孢子和孢子梗,七种孢子类型,Yeasts 酵母菌,Yeasts are fungi which typically form unicellular cells which divide by budding i.e not filamentous hyphae Most are Ascomycetous-many form asci,but there are some yeast-like forms in the Zygomycetes and BasidiomycetesBudding yeast cells considered to be conidiaVery imp

28、ortant in ecology and for man(brewing and baking)酵母菌典型情况下形成单细胞的菌体，即没有丝状菌丝，出芽繁殖。大多数是子囊菌，许多形成子囊，但在,1.Plant pathogens植物病原菌 over half of important crop pathogens are Ascomycetes.作物病原菌一半是子囊菌Helminthosporium maydis-southern corn blight玉米小斑Cryphonectria-chestnut blight-all but eliminated chestnuts in N.Ame

29、rica栗疫病Fusarium sp.-cause many wilt diseases,produce mycotoxins镰刀菌，造成萎蔫病，产毒素Botrytis-several plant diseases-can also produce very expensive sweet wine(ice wine)灰霉菌，引致几种病害，但也生产昂贵的甜葡萄酒。Claviceps-ergot fungus-causes madness-LSD source麦角菌，造成人类疾病,Some important Ascomycetes一些重要的子囊菌,1.Plant pathogens植物病原菌（

30、续）Erysiphe-powdery mildews of plants-haustoria penetrate epidermal cells of host plant 白粉菌-引致植物白粉病-吸器穿透到寄主植物表皮细胞中Ophiostoma-Dutch Elm disease 荷兰榆疫病Venturia-apple scab disease 苹果疮痂病Trichoderma-mycoparasite-use in biological control of plant disease木霉菌-真菌寄生物-用于植物病害生物防治,一些重要的子囊菌（续）,2.Food and Health 食品

31、与健康（续）Penicillium and Aspergillus-used in cheese makingThe enzymes of Penicillium camembertii produce the soft,smooth texture of Camembert and Brie cheeses.Penicillium roquefortii puts that strong flavour in blue cheeses such as Roquefort,Danish Blue,Stilton and Gorgonzola.青霉菌和曲霉菌-用于奶酪生产。青霉菌的酶产生软光滑的

32、布里白奶酪Aspergillus oryzae used in the Far East to turn soya protein into soy sauce 米曲霉在远东用于将大豆蛋白转娈成酱油Morchella(morels)-highly prized mushroom 高价的蘑菇Tuber(truffles)even more highly prized and priced!块菌，价格还要高Trichophyton and other dermatophytes(keratin-attacking fungi)eg ringworm.athletes foot,jock itch

33、etc 癣菌-足癣等,一些重要的子囊菌（续）,2.Food and Health（食品与健康）Aspergillus flavus(grows on peanuts and many other substrates,producing a mycotoxin called aflatoxin,which contaminates food and causes liver damage-the most potent carcinogen(cancer-inducing)substance known.黄曲霉（在花生和其它许多基质上生长，产生称为黄曲霉的毒素，污染食品、造成肝病-最烈性的致癌

34、剂）Fusarium graminearum,growing on feed corn,produces another mycotoxin,zearalenone,which is a steroid,and causes oestrogenic syndrome-vaginal and rectal prolapse-in young female pigs.禾谷镰刀菌，在饲料玉米上生长，产生另一种霉菌毒素即玉米烯酮，是一种固醇，造成雌激素综合症，母猪直肠下垂Penicillium italicum-example of the moulds that spoil food in stor

35、age.意大利青霉-储藏的食物变质,一些重要的子囊菌（续）,玉米烯酮,3.Rots and decomposition 腐烂与分解Cellulolytic hyphomycetes cause blue stain and soft rot of wood,discolouration and loss of strength of cotton materials and moulding of almost any damp organic substrate.分解纤维素的丝孢纲真菌木材蓝点和软腐、棉花变色和强度降低、造成任一种潮湿的有机质发霉。Ascomycetes are prime

36、colonizers and decomposers of soft plant debris,playing a vital role in the carbon and nitrogen cycles.Dominate the soil mycota in most forests.Dead leaves are colonized by aquatic hyphomycetes-tolerant of low temperatures so can grow during the winter and even under ice-make the dead leaves much mo

37、re palatable and nutritious for the various detritivorous invertebrates which eat them,子囊菌主要定殖和分解软的植物残体，在碳氮循环中起至关重要的作用。在大多数森林中制约土壤微生物区系。死叶被水中的丝孢菌定殖 耐低温因而可在冬天生长甚至在冰下生长 使死叶成为食粪类无脊椎动物的美食。,一些重要的子囊菌（续）,4.Genetics and Biotechnology 遗传和生物技术上应用Neurospora-important in classical genetics 脉孢菌-经典遗传学上应用Penicilli

38、um chrysogenum-source of penicillin.青霉菌-青霉素之源Tolypocladium niveum-source of cyclosporine-the most effective and least toxic immunosuppressant 环孢霉素之源-最有效最低毒的免疫遏制剂。Becoming used as hosts for vectors carrying genes from eukaryotic organisms.-been used to express insulin,human growth factor,human tissue

39、 plasminogen activator(used to dissolve blood clots),bovine chymosin(an enzyme used in cheese-making),and amylase and cellulase enzymes.-Have great biotechnological potential.用作带有真核生物基因的载体的宿主用来表达胰鸟素、人类生长因子，人类组织血浆酶原活化因子（用来溶解血凝块），牛凝乳酶（用来制奶酪），淀粉酶、纤维素酶等。,一些重要的子囊菌（续）,-asci contain products of one meiosis

40、 in an order reflecting segregation of alleles at first and second division.子囊中减数分裂的产物（子囊孢子）反映了第一和第二次分裂后等位基因的分离，Ascomycetes also important in study of mitotic recombination via a parasexual cycle.子囊菌在研究准性生殖中也是重要的。,Ascomycetes made major contributions to the study of meiotic recombination 对研究减数分裂重组作出了重大贡献,要点,真菌的分门：壶菌门、接合菌门、双核菌门接合菌和子囊菌的无性孢子和有性孢子子囊菌的有性生殖过程（钓状体等）子囊果、子囊、分生孢子果和分生孢子梗的类型子囊菌的分亚门，各亚门的特点重要的子囊菌（4大类）,