植物病原线虫及原生动物.ppt

分类依据是形态学的差异全世界有50多万种，在动物中是仅次于昆虫的一庞大类群Chitwood夫妇（1950）提出将线虫单独建立一个门线虫门（nematoda），再根据侧尾腺口（Phasmid）的有无，分为2个纲：侧尾腺口纲（Secernentea）和无侧尾腺口纲（Adenophorea）。植物病原线虫主要分布在垫刃目和矛线目两个目内，垫刃目属于侧尾腺口纲，矛线目属于无侧尾腺口纲。植物病原线虫的分类雌、雄虫均为线形，虫体较长，垫刃型食管，口针较小。01大都寄生禾本科植物的地上部，破坏茎、叶或子房形成虫瘿，如小麦粒线虫（A．tritici）。021.粒线虫属（Anguina）Symptomsonwheatspikes:Galledandhealthywheatspikes.ThreewheatspikesinfestedwithA.triticionleftcomparedwithhealthyspikeonright.Infectedwheatseed:Healthywheatseeds(top)andseedgallsinfectedwithA.tritici(below).茎线虫属（Ditylenchus）雌、雄虫都为线形，垫刃形食管。主要危害地下的球茎、块茎、鳞茎、块根等，如引起我国甘薯茎线虫病的破坏性茎线虫（D．destructor）。SymptomsonpodsandseedofgroundnutofDitylenchusafricanusSectionofnematode:Ditylenchusafricanusinendocarpofmaturegroundnuthullpriortoharvesting.(N=Nematodeincrosssection:NH=Nematodeheadinlongitudinalsection:MF=Malformedcellwalls)SEM:Ditylenchusafricanus(arrowed)ontheembryoofgroundnutseed,close-up.Symptoms-Ufradisease:Ufradiseaseondeepwaterrice,Bangladesh;notepartialemergenceanddistortedpaniclesduetonematodeinfection.Nematodesinbulbtissue:NematodesinfestingNarcissusbulb.SymptomsonNarcissusbulb:DamagetoNarcissusbulb.Infestedbulbsusuallyhavebrownringswhensliced.Symptomsonbean:DamagetopodsofViciafaba.Newlyformedpodstakeonadark-brownappearance.DitylenchusdestructoronpotatoDitylenchusdipsaciongarlic01滑刃线虫属（Aphelenchoides）02雌、雄虫都是线形，滑刃型食管，口针较长。主要危害植物的叶、芽，如引起水稻干尖线虫病的贝西滑刃线虫（A．bessey）。Symptomsonleaves:Left:Characteristicwhitetipsymptomonriceleaf.Right:Necroticpatchesandcrinkledriceleaves.CHLOROSIS:

AphelenchoidesfragariaeAphelenchoidesfragariaeonAfricanviolet,healthyincenterCURLINGANDTWISTINGOFLEAVESANDSTEMS:

Aphelenchoidesfragariaeonstrawberry4.异皮线虫属（Heterodera）又称胞囊线虫属。雌、雄虫异形，即雄虫细长，雌虫柠檬形。具突出的阴门锥。后期雌虫角质层变厚，呈深褐色，体内充满卵，这种含有大量的雌虫尸体称为胞囊（cyst）。该属线虫是危害植物根部的一类重要线虫，如大豆胞囊线虫（H．glycines）等。Symptomsindu