三小麥赤霉病綠色防控

III.GreenPreventionandControlofWheatScab

小麥赤霉病俗稱麥穗枯、爛麥頭、紅麥頭，是我國(guó)南方麥區(qū)冬麥類作物上重要病害之一，特別是長(zhǎng)江流域冬麥區(qū)，嚴(yán)重影響小麥的產(chǎn)量和品質(zhì)。病菌侵染后，除導(dǎo)致產(chǎn)量損失外，同時(shí)還因病粒內(nèi)含有多種毒素，可引起人、畜中毒，發(fā)生嘔吐、腹痛、頭昏等現(xiàn)象。

Wheatscab,commonlyknownaswheatearblight,rottenwheatheadandredwheathead,isoneoftheimportantdiseasesofwinterwheatcropsinthesouthernwheatregionsofChina,especiallyinthewinterwheatregionsoftheYangtzeRiverbasin,whichseriouslyaffectstheyieldandqualityofwheat.Inadditiontoyieldloss,bacterialinfectionmayalsocausepoisoningtohumansandanimalsbecauseofavarietyoftoxinscontainedintheinfectedkernels,resultinginsymptomssuchasvomiting,abdominalpainanddizziness.三

小麥赤霉病綠色防控GreenPreventionandControlofWheatScab（一）癥狀識(shí)別

SymptomIdentification

小麥自苗期至穗期均可受害，產(chǎn)生苗枯、莖基腐、稈腐和穗腐等癥狀，其中以穗腐危害最重。Wheatmaybedamagedfromtheseedlingstagetotheheadingstage,showingsymptomssuchasseedlingblight,basalstemrot,stemrot,andearrot,amongwhichearrotisthemostharmful.

穗腐一般在小麥灌漿乳熟時(shí)發(fā)生，先在小穗的基部發(fā)生淡褐色病斑，天氣潮濕時(shí)病斑擴(kuò)大呈水漬狀，以后整個(gè)小穗變?yōu)辄S褐色或枯黃色。Earrotgenerallyoccursatthefillingandmilkyripestages.Atfirst,lightbrownspotsappearatthebaseofaspikelet.Whentheweatheriswet,thespotsexpandandlooklikewaterstains.Later,thewholespikeletbecomesyellowbrownorwitheredyellow.三

小麥赤霉病綠色防控

GreenPreventionandControlofWheatScab（一）癥狀識(shí)別

SymptomIdentification

濕度大時(shí)，病部產(chǎn)生粉紅色膠質(zhì)霉層（分生孢子座及分生孢子）。麥穗成熟后期，受害部出現(xiàn)小黑點(diǎn)（子囊殼）。三

小麥赤霉病綠色防控

GreenPreventionandControlofWheatScab

Whenthehumidityishigh,apinkcolloidalmildewlayer(ofsporodochiaandconidia)wouldbegeneratedatthediseasedpart.Atthelaterstageofearripening,smallblackspots(perilhecia)wouldappearattheaffectedpart.WheatScab—PinkMildewLayerFormedatEar（一）癥狀識(shí)別

SymptomIdentification

受害的麥粒皺縮、空秕，表面有白色至粉紅色霉層。

Theaffectedkernelsareshrunkenandhollow,withawhite-to-pinkmildewlayeronthesurface.三

小麥赤霉病綠色防控GreenPreventionandControlofWheatScabHealthyGrainsDiseasedCrains（二）病原

Etiology無性態(tài)為禾谷鐮刀菌，屬半知菌亞門鐮孢菌屬真菌The

anamorphonesareFusariumgraminearum,fallingintoFusariumfungi,Deuteromycotina有性態(tài)為玉蜀黍赤霉，屬子囊菌亞門赤霉屬真菌TheteleomorphonesareGibberellazeae,fallingintoGibberellafungi,Ascomycotina小麥赤霉病菌(Wheatscabpathogen)1.子囊殼(Perithecium)

2.子囊殼縱剖面(LongitudinalSectionofPerithecium)3.子囊及子囊孢子

(AscusandAscospores)4.分生孢子座及分生孢子(ConidiosporiumandConidia)

5.分生孢子放大(AmplifiedCondidium)三

小麥赤霉病綠色防控GreenPreventionandControlofWheatScab（三）發(fā)病規(guī)律

OccurrenceRegularity

病原菌腐生能力強(qiáng)，可在多種植物殘?bào)w上越夏、越冬。帶病種子和病殘?bào)w上的子囊殼、分生孢子是下一個(gè)小麥生長(zhǎng)季節(jié)的主要初侵染來源。

Thepathogenicbacteriahaveahighsaprophyticability,andcanoversummerandoverwinteronavarietyofplantresidues.Perilheciaandconidiaoninfectedseedsandresiduesarethemainsourcesofprimaryinfectioninthenextwheatgrowingseason.三

小麥赤霉病綠色防控GreenPreventionandControlofWheatScab

小麥抽穗后至揚(yáng)花末期是最易感病期，病菌主要通過凋萎的花藥侵入小穗。子囊孢子借氣流和風(fēng)雨進(jìn)行傳播。

Wheatisthemostsusceptiblefromheadingtotheendofflowering.Mainly,thepathogeninvadesspikeletsthroughwitheredanthers.Theascosporesspreadbymeansofwindandrain.（三）發(fā)病規(guī)律該病發(fā)生的最適溫度為24～28℃，最適相對(duì)濕度為80%～100%。小麥抽穗以后降雨次數(shù)多，降雨量大，相對(duì)濕度高，極易造成赤霉病的發(fā)生和流行。地勢(shì)低洼、排水不良、粘重土壤，偏施氮肥、密度大，田間郁閉發(fā)病重。

Forthisdisease,theoptimumtemperatureis24-28℃,andtheoptimumrelativehumidityis80%-100%.Afterwheatheading,theoccurrenceandprevalenceofscabwouldbeeasilycausedbymorerainfall,heavyrainfalland/orhighrelativehumidity.Low-lyingterrain,poordrainage,stickysoil,biasedapplicationofnitrogenfertilizer,highdensityand/orcanopyclosurewouldmakeitworse.三

小麥赤霉病綠色防控GreenPreventionandControlofWheatScab（四）防治措施

Preventionandcontrolmeasures1、農(nóng)業(yè)防治

Agriculturalcontrol

因地制宜選用抗病品種，并精選種子，減少種子帶菌率。控制氮肥的施用量，按需合理施肥，氮肥作追肥時(shí)不能太晚。小麥揚(yáng)花期不能大水漫灌，多雨地區(qū)要注意排水降濕。為了減少初侵染菌源，要在小麥揚(yáng)花前盡可能處理完麥秸、玉米秸等植株殘?bào)w；作物收獲后應(yīng)及時(shí)翻耕滅茬，盡快促使植株病殘?bào)w腐爛(漚肥)，減少田間菌源的數(shù)量；小麥成熟后要及時(shí)收割脫粒曬干，減少霉垛造成的損失。Selectdisease-resistantcultivarsbasedonlocalconditions,andselecteliteseedstoreducethebacterialbearingrate.Controltheamountofnitrogenfertilizertobeapplied,applyfertilizerreasonablyasneeded,andnitrogenshouldnotbeappliedtoolateastopdressing.Nofloodirrigationisallowedduringwheatflowering,anddrainageanddampnessreductionshouldbeenhancedinrainyareas.Inordertoreducethesourceofprimaryinfection,plantresiduessuchaswheatstrawandcornstrawshouldbetreatedasmuchaspossiblebeforewheatflowering;aftercropharvest,thefieldshouldbeplowedandstubbleremovedimmediatelytofacilitatethedecompositionofplantresidues(makingcompost)assoonaspossible,andreducethenumberofmicrobialsourcesinthefield;andthewheatshouldbeharvested,threshedanddriedinatimelymannerwhenitisripe,reducingthelossescausedbymoldystacks.三

小麥赤霉病綠色防控

GreenPreventionandControlofWheatScab

2、藥劑防治

Chemicalcontrol

種子處理是防治芽腐和苗枯的有效措施，可選用50％多菌靈可濕性粉劑，每100kg種子用藥

100～200g濕拌。Seedtreatmentisaneffectivemeasuretopreventandcontrolbudrotandseedlingwithering.50%carbendazimwettablepowdermaybeused,100-200gforevery100k