鞭毛菌亚门真菌Mastigomycotina

第二节

鞭毛菌亚门真菌

Mastigomycotina

特点：Fungihavingflagellatedzoosporesandgametesareincludedunderthesub-divisionmastigomycotina.Thesehavecoenocytichyphae.Someofthemliveinwater.常见病害：根肿、猝倒、霜霉病、疫病，在潮湿多雨低洼积水，通风透光差的条件下易发生

多数水生，少数陆生．营养体主为无隔菌丝和原生质体，无性生殖产生游动孢子，多数有性繁殖产生卵孢子1、生活习性及营养菌丝：Theyhavecoenocytichyphaorplasmodium.2、有性繁殖及无性繁殖：无性生殖产生游动孢子，有性生殖产生休眠孢子囊和卵孢子。3、分类：根肿菌纲Plasmodiophoromycetes

壶菌纲Chytridiomycetes

丝壶菌纲Hyphochytridiomycetes

卵菌纲Oomycetes游动孢子类型图一、根肿菌纲

Anteriorlybiflagellatezoospores;bothofwhiplashtypebutunequalinlength.1、基本特点：营养体为原生质体，有性繁殖产生休眠孢子囊，全部为专性寄生。游动孢子双鞭毛，尾鞭，顶生，长短不等。2、代表菌

根肿菌属：十字花科根肿病

粉痂属：马铃薯粉痂症状、病原根肿菌属：Plasmodiophora芸薹根肿Plasmodiophorabrassiae引起十字花科根肿病。症状病原发生规律防治方法根肿菌属白菜根肿病白菜根肿病白菜根肿病原图

白菜根肿病原图粉痂属：Spongspora马铃薯粉痂病Spongspora

subterranea二、壶菌纲Chytridiomycetes

Zoosporeswithasingleposteriorwhiplashflagellumandaconspicuousnuclearcap.1、基本特点：营养体多为多核的单细胞，有假根。有性繁殖复杂。游动孢子单尾鞭。大多数水生，有四个目，其中壶菌目最为重要。壶菌目菌体图2、代表病菌：

节壶菌属：玉米褐斑病病状

病原

集壶菌：马铃薯癌肿

节壶菌属：Physoderma玉米节壶菌：P.maydis引起玉米褐斑病。症状病原发生规律防治方法

玉米褐斑病图

节壶菌休眠孢子图集壶菌属Synchytricum

内生集壶菌引起马铃薯癌肿病三、卵菌纲Oomycetes

Laterallybiflagellate,flagellaofequalsize;onewhiplashtheotheroftinseltype.Sometimesanteriorlybiflagellate.

1、基本特点:

(1)营养体多数为发达的二倍体的无隔菌丝(2)细胞壁为纤维素(3)无性繁殖产生游动孢子囊和游动孢子，有性繁殖产生卵孢子(4)分为四个目：Saprolegniales，Leptomitales，

lagenidiales,Peronosporales.其中Saprolegniales和Peronosporales是重要的植物病原2、水霉目Saprolengniales以水生为主，少数陆生游动孢子囊丝状、圆筒状或梨状，具有孢子囊层出现象和游动孢子两游现象。

如，水霉和稻绵霉。Asexualreproductionisaccomplishedbythezoospores.Cylindricalzoosporangiadevelopatthetipsofhyphaewhichproducenumerousbiflagellatezoospores.Whenmature,theycanbeseenjostlingoneanotherwithinthezoosporangium.水霉属图孢子囊层出现象：Sporangialproliferation:ItisaninterestingphenomenoncharacteristicofSaporlegnia,whicheablestheformationofseveralsporangiaatthesamesite.Whenazoosporangiumhasliberatedtheprimaryzoospores,asecondzoosporangiumisformedwithintheoldone,whichpushesoutoftheremnantsoftheprevioussporangium,andsoon.游动孢子两游现象

Dimorphism(Diplanetism):.Theapically-biflagellateprimryzoospores,whichareliberatedthroughaporeatthetipofthezoosporangium,swimaboutforsometime,cometorestandencyst,withdrawtheflagellaandformathinwall.Afterashortperiodofrest,apapilladevelopsonthecyst;itstipdissolvesandareniformzoosporebearingtwolateralflagellacreepsoutleavingtheemptycystbehind.Thesecondzoosporecomestorestandformsacyst.Thecystgerminatesbyformingahyphawhichformsanewcolony水稻绵霉病幼苗期发病水稻绵霉症状1水稻绵霉症状2水霉属Saprolegnia主要引起鱼（动物）病等感

染

水

霉

病

的

鱼丝囊菌属Aphanomyces丝囊菌引起萝卜根腐3、霜霉目Peronosporales无两游现象，游动孢子囊大多数为球形。卵孢子为单卵球。ThegenerabelongingtoPeronosporalesshowmorphologicalchangeswhicharemoresuitedtotheamphibiousorterrestrialhabitatofthesefungi.Sporangiaindryweatherinsteadofformingzoosporesgerminatedirectlybygermthbe,thusbehavingasconidia.Theintercellularhypheaofparasiticgeneraformhaustoriawhichenterhostcellsandabsorbnutrients.Pythiaceae,Peronophthoraceae,Albuginaceae,Peronosporaceae.（1）腐霉属Pythium：重要病原，主要引起腐烂如引起腐烂的瓜果腐霉和幼苗猝倒。主要存在于土壤中。P.debaryanum—Dampingoffoftobaccoandchillies.P.aphanidermatum—Softrotofpapaya,dampingoffofpotato.P.graminicolum—Rhizomeandrootrotofturmertic.P.myriotylum—‘Footrot’ofginger.瓜果腐霉图猝倒病原猝倒病图猝倒病图猝倒病图猝倒病图腐霉引起腐烂病害控制Control:DampingoffofseedlingsandrootrotscausedbyPythiumaremorecommoninsoilsofhighwaterandhumuscontent,Thus,waterlogginginfieldsshouldbeavoided.Soilsterilizationtokillthefungusisdonethroughfungicides.Butbettermethodofcontrolistotreattheseedsbeforesowingwithprotectivefungicides.（2）疫霉属PhytophthoraPhytophthorasurvivesinthedeadhosttissuesleftinthesoil.P.infestans,asarule,survivesasdormantmyceliumininfectedpotatotubers.However,itcanbeculturedinlaboratory番茄晚疫病

辣椒疫病等

疫霉属（Phytophthora)

游动孢子囊梨形．为害根，茎基部，也有为害地上部，引起腐烂称为疫病．如牡丹疫病，五色椒疫病等，高温高湿易发病．土传或气传Phytophthorainfestans:thesediseseisworldwideinoccurrenceandisreportedalsofromallpartsofworld.Alowtemperture(18~20),accompaniedbyhighrelativehumidity(91~100%),aretherequisitesforsporangialproduction.Sporangiophoresemergethroughthestomatafromthelowersurfaceofinfectedleavesandbearterminally,lemonshapedsporangawithadistinctbeak.Thesporangiaarehighlysusceptibletodesiccation.晚疫病（图）晚疫病原图辣椒疫病番茄晚疫番茄晚疫（3）霜疫霉Peronophthora

P.litchii

causethediseaseoflitchii.霜疫霉属图荔枝霜疫霉荔枝霜疫霉荔枝霜疫霉荔枝霜疫霉（4）白锈属

Albugo孢囊梗棍棒状，上着生球形游动孢子囊。寄生双子叶植物叶片等，引起表皮形成白色庖状突起。如油菜白锈、牵牛花白锈病,菊花白锈病等。Thegenushas25species,allobligateparasitesofhigherplants,causingwhiteblisters(areasofraisedhostepidermis)onthefoliage.Club-shapedsporangiophoresofdeterminategrowth,withthicklateralwallsandathinapex,arisetoformapalisadelayer.Thesecutmultinucleatesporangiawhichremainattachedtoformachainattheapex.白锈属图白锈属图白锈属图白锈病白锈病白锈病白锈病（5）霜霉科Peronosporaceae

Theycause‘downymildew’diseasesofseveralimportantcrops.Thename‘downymildew’isgivenbecauseofthehangingsporangiophoresfromthelowersurfaceofleavesthroughstomata.Thesporangiaphoresbranchandbearsporangiaattheirtips.Thesporangiausuallybehaveasconidia.Thevariousgeneraareidentifiedonthebasisofthecharacteristicbranchingoftheirsporangiophores.Thei