《植物病虫害绿色防控技术》课件——二、玉米丝黑穗病绿色防控（双语版）.pptx

;玉米丝黑穗病俗称乌米、哑玉米，是玉米产区的重要病害，在华北、东北、华中、西南、华南和西北地区普遍发生，尤以北方春玉米区、西南丘陵山地玉米区和西北玉米区发病较重。一般年份发病率2％～8％，严重地块可达60％～70％，造成严重减产。

Maizeheadsmut,commonlyknownasblackriceanddumbcorn,isanimportantdiseaseincornproducingareas.ItoccurswidelyinNorthChina,NortheastChina,CentralChina,SouthwestChina,SouthChinaandNorthwestChina,especiallyinspringcornareasinthenorth,hillyandmountainouscornareasinthesouthwestandnorthwestcornareas.Theincidencerateingeneralyearsis2%–8%,andoreven60%–70%insevereplots,resultinginseriousyieldreduction.;（一）症状识别Symptomidentification

玉米丝黑穗病是苗期侵染的系统性侵染病害，主要侵害玉米雌穗和雄穗。穗期出现典型症状，主要有两种类型：一是黑穗型，除苞叶外整个果穗变成一个大黑粉苞，基部膨大而顶端小、不吐花丝、苞叶通常不易破裂、黑粉不外漏、不易飞散、常黏结成块，内部夹杂丝状的寄主维管束组织，初期外面包被白膜，后期膜破裂后，才露出黑粉；二是变态畸形穗，受害较轻的雌穗，可保持灌浆期的粒形，但籽粒压破后仍为黑粉，基部籽粒成3～5cm长的芽状物或畸形成丛生的小叶状物，内含有少量黑粉。

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

诊断要点：除苞叶外整个果穗变成一个大黑粉苞，黑粉常黏结成块，内部夹杂丝状的寄主维管束组织。

Diagnosticpoints:Exceptforbracts,thewholefruitclusterbecomesalargeblack