《植物病蟲害綠色防控技術(shù)》課件-二、玉米絲黑穗病綠色防控（雙語(yǔ)版）

二

玉米絲黑穗病綠色防控

II.GreenPreventionandControlofMaizeHeadSmut

玉米絲黑穗病俗稱烏米、啞玉米，是玉米產(chǎn)區(qū)的重要病害，在華北、東北、華中、西南、華南和西北地區(qū)普遍發(fā)生，尤以北方春玉米區(qū)、西南丘陵山地玉米區(qū)和西北玉米區(qū)發(fā)病較重。一般年份發(fā)病率2％～8％，嚴(yán)重地塊可達(dá)60％～70％，造成嚴(yán)重減產(chǎn)。

Maizeheadsmut,commonlyknownasblackriceanddumbcorn,isanimportantdiseaseincornproducingareas.ItoccurswidelyinNorthChina,NortheastChina,CentralChina,SouthwestChina,SouthChinaandNorthwestChina,especiallyinspringcornareasinthenorth,hillyandmountainouscornareasinthesouthwestandnorthwestcornareas.Theincidencerateingeneralyearsis2%–8%,andoreven60%–70%insevereplots,resultinginseriousyieldreduction.二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut（一）癥狀識(shí)別

Symptomidentification

玉米絲黑穗病是苗期侵染的系統(tǒng)性侵染病害，主要侵害玉米雌穗和雄穗。穗期出現(xiàn)典型癥狀，主要有兩種類型：一是黑穗型，除苞葉外整個(gè)果穗變成一個(gè)大黑粉苞，基部膨大而頂端小、不吐花絲、苞葉通常不易破裂、黑粉不外漏、不易飛散、常黏結(jié)成塊，內(nèi)部夾雜絲狀的寄主維管束組織，初期外面包被白膜，后期膜破裂后，才露出黑粉；二是變態(tài)畸形穗，受害較輕的雌穗，可保持灌漿期的粒形，但籽粒壓破后仍為黑粉，基部籽粒成3～5cm長(zhǎng)的芽狀物或畸形成叢生的小葉狀物，內(nèi)含有少量黑粉。

Maizeheadsmutisasystematicinfectiondiseaseintheseedlingstage,mainlyaffectingthefemaleandmaleearsofmaize.Typicalsymptomsappearattheearstage,mainlytwotypes:Thefirstistheblackeartype.Exceptforthebracts,thewholefruitearbecomesalargeblackpollenbud.Thebaseisenlargedandthetipissmall,withoutfilamentspitting.Thebractsareusuallynoteasytobreak,theblackpowderisnotexposed,noteasytofly,andoftensticksintoblocks.Therearefilamentoushostvascularbundletissuesinside.Theouterpartiscoatedwithwhitefilmattheinitialstage,andtheblackpowderisexposedonlyafterthefilmrupturesatthelaterstage.Thesecondtypeismetamorphicanddeformedears.Femaleearsthatarelessdamagedcanmaintainthegrainshapeduringthefillingstage,butthegrainsarestillblackpowderafterbeingcrushed,andthebasegrainsform3–5cmlongbudsorclusteredleafletswithasmallamountofblackpowder.

診斷要點(diǎn)：除苞葉外整個(gè)果穗變成一個(gè)大黑粉苞，黑粉常黏結(jié)成塊，內(nèi)部夾雜絲狀的寄主維管束組織。

Diagnosticpoints:Exceptforbracts,thewholefruitclusterbecomesalargeblackpowderbud,whichisoftenbondedintoblocks,withfilamentoushostvascularbundletissueinside.二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut雄穗癥狀Symptomsoftassels雌穗癥狀Symptomsofears二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut變態(tài)畸形穗Abnormalanddeformedears二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut

病苗矮化，節(jié)間縮短，株型彎曲，莖基稍粗，分蘗增多，葉片密集，色濃綠

Thediseasedseedlingsaredwarfed,theinternodesareshortened,theplantiscurved,thestembaseisslightlythick,thetillersareincreased,theleavesaredense,whichisdarkgreen.二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut（二）病原

Pathogens

病原為絲軸黑粉菌，屬擔(dān)子菌亞門，軸黑粉菌屬。果穗散出的黑粉為冬孢子，冬孢子球形或近球形，表面有細(xì)刺。冬孢子間混雜有球形或近球形的不育細(xì)胞，表面光滑近無(wú)色。在成熟前冬孢子常集合成孢子球，外面由菌絲組成的薄膜包圍著，成熟的冬孢子分散后遇適宜條件萌發(fā)產(chǎn)生有隔的擔(dān)子(先菌絲)，側(cè)生擔(dān)孢子。擔(dān)孢子單孢，無(wú)色，橢圓形。

ThepathogenisSphacelotheca,whichbelongstotheBasidiomycotinaandSphacelotheca.Theblackpowderscatteredfromthefruitclustersisteliospores,whicharesphericalornearlyspherical,withfinespinesonthesurface.Theteliosporesaremixedwithsphericalornearlysphericalsterilecells,withasmoothandnearlycolorlesssurface.Beforematurity,teliosporesoftengathertoformsporebulbs,whicharesurroundedbyafilmcomposedofhyphae.Afterdispersing,matureteliosporesgerminateundersuitableconditionstoproduceseptatebasidiospores(promycelium)andlateralbasidiospora.Thebasidiosporaismonosporous,colorless,andoval.病原菌冬孢子和冬孢子萌發(fā)Pathogenicbacteriateliosporesandgerminationofteliospores二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut（三）發(fā)生規(guī)律

OccurrenceRegularity玉米絲黑穗病菌以冬孢子散落在土壤中、混入糞肥中或沾附在種子表面越冬。冬孢子在土壤中能存活2～3年以上。帶菌種子是遠(yuǎn)距離傳播的重要途徑，但由于種子自然帶菌量小，傳病作用明顯低于糞肥和土壤帶菌。

Themaizeheadsmutscattersinthesoilasteliospores,mixesinmanure,oradherestothesurfaceofseedsforoverwintering.Teliosporescansurviveinsoilformorethan2–3years.Bacteria-carryingseedsareanimportantwayoflong-distancetransmission.However,duetothesmallnaturalnumberofbacteria-carryingseeds,thediseasetransmissioneffectissignificantlylowerthanthatofmanureandsoil.

二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut二玉米絲黑穗病綠色防控

II.GreenPreventionandControlofMaizeHeadSmut

玉米絲黑穗病菌冬孢子萌發(fā)后在土壤中直接侵入玉米幼苗的分生組織，病菌侵染最適時(shí)期是從種子破口露出白尖到幼芽長(zhǎng)到1～1.5cm時(shí)，幼芽出土前是病菌侵染的關(guān)鍵階段。由此，幼芽出土前的溫濕度、播種深度、出苗快慢、土壤中的病菌含量等因素，與玉米絲黑穗病的發(fā)生程度關(guān)系密切。此病發(fā)生適溫為20～25℃，土壤適宜含水量為18%～20%，土壤冷涼、干燥，有利于病菌侵染。

Theteliosporesofheadsmutfungusofmaizedirectlyinvadethemeristemofmaizeseedlingsaftergermination.Theoptimalperiodofpathogeninfectionisfromthetimewhenthewhitetipoftheseedruptureisexposedtothetimewhenthebudgrowsto1~1.5cm.Thekeystageofpathogeninfectionisbeforethebudemergesfromthesoil.Therefore,thetemperatureandhumidity,sowingdepth,seedlingemergencespeed,pathogencontentinthesoilandotherfactorsbeforethebudemergencearecloselyrelatedtotheoccurrencedegreeofmaizeheadsmut.Thesuitabletemperaturefortheoccurrenceofthediseaseis20~25°C,thesuitablewatercontentofthesoilis18%~20%,andthesoiliscoolanddry,whichisconducivetopathogeninfection.

玉米不同品種的抗病性有明顯差異，抗病品種很少發(fā)?。贿B作地發(fā)病重，輪作地發(fā)病輕；使用未腐熟的廄肥，種子帶菌未經(jīng)消毒，病株殘?bào)w未被妥善處理等都會(huì)使土壤菌量增加，導(dǎo)致該病的嚴(yán)重發(fā)生；播種過(guò)深、種子生活力過(guò)弱時(shí)發(fā)病重；在土壤含水量20％條件下發(fā)病率最高。

Thediseaseresistanceofdifferentcultivarsofmaizeissignificantlydifferent,anddisease-resistantcultivarsrarelysufferfromthedisease.Thediseaseisseriousoncontinuouscroppingsitesandmildonrotationsites.Theuseofundecomposedbarnyardmanure,undisinfectedseeds,andimproperdisposalofdiseasedplantresidueswillincreasetheamountofsoilbacteria,resultinginseriousoccurrenceofthedisease.Thediseaseisseriouswhentheseedsaresowntoodeeplyandtheseedvitalityistooweak.Theincidenceisthehighestatthesoilmoisturecontentof20%.二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut（四）防治技術(shù)

ControlTechnique

以種子處理為主，采用及時(shí)消滅菌源、種植抗病品種等農(nóng)業(yè)措施相結(jié)合的綜合防治措施。Seedtreatmentisthemainmethod,andcomprehensivecontrolmeasuressuchastimelyeliminationofsterilizationsourcesandplantingofdisease-resistantvarietiesareadopted.

1、種子處理

Seedtreatment

在選擇抗病良種的前提下，播前要曬種，選籽粒飽滿、發(fā)芽勢(shì)強(qiáng)、發(fā)芽率高的種子，再用藥劑拌種處理?？蛇x用多菌靈，或萎銹靈處理。在拌種時(shí)拌藥一定要均勻，攪拌數(shù)次，讓種子將藥液吸干凈，晾干后待播，確保防治效果。Onthepremiseofselectingdisease-resistantgoodseeds,suntheseedsbeforesowing,selectseedswithfullgrains,stronggerminationvigor,andhighgerminationrate,andthenmixtheseedswithchemicals.Carbendazimorcarboxincanbeused.Whenmixingtheseeds,thechemicalsmustbemixedevenlyandstirredmsnytimestoallowtheseedstosuckupthechemicalsolutionanddryitbeforesowingtoensurethecontroleffect.二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut

2、農(nóng)業(yè)防治

Agriculturalpreventionandcontrol

杜絕和減少初侵染源，不從病區(qū)調(diào)運(yùn)種子；育苗移栽的要選不帶菌的地塊或經(jīng)土壤處理后再育苗，最好在玉米苗、3～4片葉以后再移栽定植大田，可有效避免絲黑穗病菌的侵染；及時(shí)拔除田間病株能有效地減少土壤中越冬菌源；進(jìn)行高溫堆肥，廄肥充分發(fā)酵，殺死病原菌后再施用；切忌將病株散放或喂養(yǎng)牲畜、墊圈等；一般實(shí)行1～3年的合理輪作，可有效地控制絲黑穗病的發(fā)生和危害。

Eliminateandreduceprimaryinfectionsourcesanddonottransportseedsfromendemicareas.Forseedlingtransplanting,selectplotswithoutbacteriaorraiseseedlingsaftersoiltreatment.Itisbesttotransplantcornseedlingsand3–4leavesbeforefieldplanting,whichcaneffectivelyavoidtheinfectionofheadsmutfungus.Timelyremovalofdiseasedplantsinthefieldcaneffectivelyreduceoverwinteringpathogensourcesinthesoil.Performhigh-temperaturecomposting,fullyfermentthestablemanure,andapplyitafterkillingpathogenicbacteria.Donotspreadorfeeddiseasedplantstolivestock,gaskets,etc.Generally,reasonablecroprotationfor1–3yearscaneffectivelycontroltheoccurrenceanddamageofmaizeheadsmut.二玉米絲黑穗病綠色防控II.GreenPreventionandControlofMaizeHeadSmut二玉米絲黑穗病綠色防