鞭毛菌亞門真菌Mastigomycotina

第二節(jié)

鞭毛菌亞門真菌

Mastigomycotina

特點(diǎn)：Fungihavingflagellatedzoosporesandgametesareincludedunderthesub-divisionmastigomycotina.Thesehavecoenocytichyphae.Someofthemliveinwater.常見病害：根腫、猝倒、霜霉病、疫病，在潮濕多雨低洼積水，通風(fēng)透光差的條件下易發(fā)生

多數(shù)水生，少數(shù)陸生．營養(yǎng)體主為無隔菌絲和原生質(zhì)體，無性生殖產(chǎn)生游動(dòng)孢子，多數(shù)有性繁殖產(chǎn)生卵孢子1、生活習(xí)性及營養(yǎng)菌絲：Theyhavecoenocytichyphaorplasmodium.2、有性繁殖及無性繁殖：無性生殖產(chǎn)生游動(dòng)孢子，有性生殖產(chǎn)生休眠孢子囊和卵孢子。3、分類：根腫菌綱Plasmodiophoromycetes

壺菌綱Chytridiomycetes

絲壺菌綱Hyphochytridiomycetes

卵菌綱Oomycetes游動(dòng)孢子類型圖一、根腫菌綱

Anteriorlybiflagellatezoospores;bothofwhiplashtypebutunequalinlength.1、基本特點(diǎn)：營養(yǎng)體為原生質(zhì)體，有性繁殖產(chǎn)生休眠孢子囊，全部為專性寄生。游動(dòng)孢子雙鞭毛，尾鞭，頂生，長短不等。2、代表菌

根腫菌屬：十字花科根腫病

粉痂屬：馬鈴薯粉痂癥狀、病原根腫菌屬：Plasmodiophora蕓薹根腫Plasmodiophorabrassiae引起十字花科根腫病。癥狀病原發(fā)生規(guī)律防治方法根腫菌屬白菜根腫病白菜根腫病白菜根腫病原圖

白菜根腫病原圖粉痂屬：Spongspora馬鈴薯粉痂病Spongspora

subterranea二、壺菌綱Chytridiomycetes

Zoosporeswithasingleposteriorwhiplashflagellumandaconspicuousnuclearcap.1、基本特點(diǎn)：營養(yǎng)體多為多核的單細(xì)胞，有假根。有性繁殖復(fù)雜。游動(dòng)孢子單尾鞭。大多數(shù)水生，有四個(gè)目，其中壺菌目最為重要。壺菌目菌體圖2、代表病菌：

節(jié)壺菌屬：玉米褐斑病病狀

病原

集壺菌：馬鈴薯癌腫

節(jié)壺菌屬：Physoderma玉米節(jié)壺菌：P.maydis引起玉米褐斑病。癥狀病原發(fā)生規(guī)律防治方法

玉米褐斑病圖

節(jié)壺菌休眠孢子圖集壺菌屬Synchytricum

內(nèi)生集壺菌引起馬鈴薯癌腫病三、卵菌綱Oomycetes

Laterallybiflagellate,flagellaofequalsize;onewhiplashtheotheroftinseltype.Sometimesanteriorlybiflagellate.

1、基本特點(diǎn):

(1)營養(yǎng)體多數(shù)為發(fā)達(dá)的二倍體的無隔菌絲(2)細(xì)胞壁為纖維素(3)無性繁殖產(chǎn)生游動(dòng)孢子囊和游動(dòng)孢子，有性繁殖產(chǎn)生卵孢子(4)分為四個(gè)目：Saprolegniales，Leptomitales，

lagenidiales,Peronosporales.其中Saprolegniales和Peronosporales是重要的植物病原2、水霉目Saprolengniales以水生為主，少數(shù)陸生游動(dòng)孢子囊絲狀、圓筒狀或梨狀，具有孢子囊層出現(xiàn)象和游動(dòng)孢子兩游現(xiàn)象。

如，水霉和稻綿霉。Asexualreproductionisaccomplishedbythezoospores.Cylindricalzoosporangiadevelopatthetipsofhyphaewhichproducenumerousbiflagellatezoospores.Whenmature,theycanbeseenjostlingoneanotherwithinthezoosporangium.水霉屬圖孢子囊層出現(xiàn)象：Sporangialproliferation:ItisaninterestingphenomenoncharacteristicofSaporlegnia,whicheablestheformationofseveralsporangiaatthesamesite.Whenazoosporangiumhasliberatedtheprimaryzoospores,asecondzoosporangiumisformedwithintheoldone,whichpushesoutoftheremnantsoftheprevioussporangium,andsoon.游動(dòng)孢子兩游現(xiàn)象

Dimorphism(Diplanetism):.Theapically-biflagellateprimryzoospores,whichareliberatedthroughaporeatthetipofthezoosporangium,swimaboutforsometime,cometorestandencyst,withdrawtheflagellaandformathinwall.Afterashortperiodofrest,apapilladevelopsonthecyst;itstipdissolvesandareniformzoosporebearingtwolateralflagellacreepsoutleavingtheemptycystbehind.Thesecondzoosporecomestorestandformsacyst.Thecystgerminatesbyformingahyphawhichformsanewcolony水稻綿霉病幼苗期發(fā)病水稻綿霉癥狀1水稻綿霉癥狀2水霉屬Saprolegnia主要引起魚（動(dòng)物）病等感

染

水

霉

病

的

魚絲囊菌屬Aphanomyces絲囊菌引起蘿卜根腐3、霜霉目Peronosporales無兩游現(xiàn)象，游動(dòng)孢子囊大多數(shù)為球形。卵孢子為單卵球。ThegenerabelongingtoPeronosporalesshowmorphologicalchangeswhicharemoresuitedtotheamphibiousorterrestrialhabitatofthesefungi.Sporangiaindryweatherinsteadofformingzoosporesgerminatedirectlybygermthbe,thusbehavingasconidia.Theintercellularhypheaofparasiticgeneraformhaustoriawhichenterhostcellsandabsorbnutrients.Pythiaceae,Peronophthoraceae,Albuginaceae,Peronosporaceae.（1）腐霉屬Pythium：重要病原，主要引起腐爛如引起腐爛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.瓜果腐霉圖猝倒病原猝倒病圖猝倒病圖猝倒病圖猝倒病圖腐霉引起腐爛病害控制Control:DampingoffofseedlingsandrootrotscausedbyPythiumaremorecommoninsoilsofhighwaterandhumuscontent,Thus,waterlogginginfieldsshouldbeavoided.Soilsterilizationtokillthefungusisdonethroughfungicides.Butbettermethodofcontrolistotreattheseedsbeforesowingwithprotectivefungicides.（2）疫霉屬PhytophthoraPhytophthorasurvivesinthedeadhosttissuesleftinthesoil.P.infestans,asarule,survivesasdormantmyceliumininfectedpotatotubers.However,itcanbeculturedinlaboratory番茄晚疫病

辣椒疫病等

疫霉屬（Phytophthora)

游動(dòng)孢子囊梨形．為害根，莖基部，也有為害地上部，引起腐爛稱為疫病．如牡丹疫病，五色椒疫病等，高溫高濕易發(fā)?。羵骰驓鈧鱌hytophthorainfestans:thesediseseisworldwideinoccurrenceandisreportedalsofromallpartsofworld.Alowtemperture(18~20),accompaniedbyhighrelativehumidity(91~100%),aretherequisitesforsporangialproduction.Sporangiophoresemergethroughthestomatafromthelowersurfaceofinfectedleavesandbearterminally,lemonshapedsporangawithadistinctbeak.Thesporangiaarehighlysusceptibletodesiccation.晚疫病（圖）晚疫病原圖辣椒疫病番茄晚疫番茄晚疫（3）霜疫霉Peronophthora

P.litchii

causethediseaseoflitchii.霜疫霉屬圖荔枝霜疫霉荔枝霜疫霉荔枝霜疫霉荔枝霜疫霉（4）白銹屬

Albugo孢囊梗棍棒狀，上著生球形游動(dòng)孢子囊。寄生雙子葉植物葉片等，引起表皮形成白色庖狀突起。如油菜白銹、牽牛花白銹病,菊花白銹病等。Thegenushas25species,allobligateparasitesofhigherplants,causingwhiteblisters(areasofraisedhostepidermis)onthefoliage.Club-shapedsporangiophoresofdeterminategrowth,withthicklateralwallsandathinapex,arisetoformapalisadelayer.Thesecutmultinucleatesporangiawhichremainattachedtoformachainattheapex.白銹屬圖白銹屬圖白銹屬圖白銹病白銹病白銹病白銹?。?）霜霉科Peronosporaceae

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