第五节昆虫病原原生动物ppt课件.ppt

第五节 原生动物杀虫剂,主要内容,一、昆虫病原原生动物的特性二、昆虫病原原生动物的种类三、昆虫微孢子虫及其应用,一、昆虫病原原生动物的特性,原生动物是一类体型最小、构造最简单的动物。一般为单细胞，需用显微镜才能看到。它的细胞结构与高等动物细胞基本相同，具有细胞膜、细胞质和一个或数个细胞核，它们是单细胞生物，没有器官分化，然而它们在运动摄食、繁殖和排泄等方面却有与多细胞动物几乎同样的生理机能。原生动物的营养方式有三种：植物性营养、动物性营养和腐生性营养。,一、昆虫病原原生动物的特性,1.单细胞真核生物2.细胞内专性寄生物，不能在人工培养基上生长，通常采用活寄主繁殖。3.侵染：原生动物的感染常发生在寄主幼虫期，经口摄入孢子、孢囊或原生动物的其他发育阶段，也有些种类可附着在寄主卵表面或在卵内传播。,生活史,4.病症：在自然情况下可引起慢性病，患病寄主极少表现出明显的病症，仅表现出行动迟缓、食欲缺乏，生长发育不正常。在感病过程中，寄主未发育成熟即死亡。有些种类则能引起细菌败血症，导致寄主快速死亡。,二、昆虫病原原生动物的种类及生物学特性,有毛根足门真孢子虫门奇嵌孢虫门纤毛虫门微孢子虫门,Sarcomastigophora有毛根足门,细胞含一细胞核有性生殖为配子生殖运动胞器是鞭毛或伪足或两者皆有,Apicomplexa 真孢子虫门,生活史一定阶段存在顶复合器结构，并在某些阶段存在微孔无纤毛全部寄生,Ascetospora 奇嵌孢虫门,孢子多细胞或单细胞，内含1个或多个孢质，无极囊或极丝主要为水生无脊椎动物的寄生虫,纤毛虫门 Ciliophora,生活史一定阶段至少有纤毛或复合纤毛器，即使无纤毛时也存在表膜下纤毛系统，两型核无性生殖为横向二分裂，也有出芽和复分裂，有性生殖为接合生殖、自体受精和细胞受精通常有伸缩泡异养，大多数自由生活,Microspora 微孢子虫门,孢子单细胞，壁无孔，含有单核或双核的孢质及简单或复杂的射出器，射出器有极管或极帽，无线粒体全部寄生,1.外膜2.中层膜3.内膜4.内质膜5.具二核6.后极泡7.极锚8.极体9.极丝10.极孔,Diagrammatic illustration of a cut away view through a microsporidian spore.Modified from Vavra,J.1976.Structure of the Microsporidia.In L.A.Bulla and T.C.Cheng(Eds.),Comparative Pathobiology,Plenum Press,New York,1:1-85 and from I.V.Issi(1986),Microsporidia as a phylum of parasitic protozoa,Acad.Sci.USSR“Protozoology”(Leningrad)10:6-136.Abbreviations as above but including PB=posterior body,N=nucleus,VPL=Vesicular part of the polaroplast.(T.G.Andreadis),SEM of a germinated spore of Nosema algerae.(J.J.Becnel),SEM of meiospores of the microsporidium Parathelohania legeri from larvae of the mosquito Anopheles maculipennis(五斑按蚊).(J.J.Becnel),Light microscope interference contrast micrograph of a Vairimorpha species from the gypsy moth,Lymantria dispar.Uninucleate octospores.Note the presence of an interfacial envelope and that some packets contain fewer than 8 spores.(J.V.Maddox),Light microscope interference contrast micrograph of environ-mental spores of a Nosema species from the gypsy moth,Lymantria dispar.Fresh preparation,unstained.(J.V.Maddox),LM interference contrast micrograph of environmental spores of a Caudospora sp.(尾孢虫属)from a black fly larva(Prosimulium sp.原蚋).Fresh preparation,unstained.(J.V.Maddox),LM phase contrast micrograph of environmental spores of Edhazardia aedis from the mosquito Aedes aegypti.(T.G.Andreadis),LM phase contrast micrograph of a germinated uninucleate spore of Edhazardia aedis that is responsible for horizontal transmission.(J.J.Becnel),LM interference contrast micrograph of the uninucleate,pyriform spore of Edhazardia aedis in an India ink preparation demonstrating the mucoca-lyx surrounding the spore.(J.J.Becnel),LM phase contrast micrograph of Thelohania(泰罗汉孢虫属)solenopsae from Solenopsis invicta.Both octospores and free spores are present.(J.J.Becnel),Light microscope phase contrast micrograph of spores of Ovavesicula popillae from the Japanese beetle,Popillia japonica.(T.G.Andreadis),LM phase contrast micrograph of Nosema lymantriae primary spores in the midgut epithelium.Fresh preparation,no stain.Primary spores are responsible for transmitting the infection from one cell to another.Fresh preparation,unstained.(L.F.Solter),LM bright field micrograph of Nosema trichoplusiae from the cabbage looper,Trichoplusia ni.Spores were fixed in methanol and stained in aqueous Giemsa.(J.V.Maddox),LM bright field micrograph of Nosema trichoplusiae from the cabbage looper,Trichoplusia ni.Spores were fixed in methanol and stained in aqueous Giemsa.(J.V.Maddox),LM bright field micrograph of Endoreticulatus(内网虫属)schubergi from the lawn webworm,Crambus trisectus(草螟).Spores were fixed in methanol and stained in aqueous Giemsa.(J.V.maddox),LM bright micrograph of Nosema muscidifuracis in an infected cell of the hymenopteran parasitoid of the fly,Muscidifurax raptor.The cytoplasm contains sporoblasts,immature spores,and mature spores.Fixed in methanol and stained in aqueous Giemsa.(J.J.Becnel),Merogonic Cycle TEM of a diplokaryotic meront of Amblyospora connecticus from the mosquito Aedes cantator.(T.G.Andreadis),TEM of Vairimorpha necatrix from the armyworm,Pseudaletia unipuncta.Meront in midgut epithelial cell,24 hours post infection.This meront could be uninucleate or binucleate,depending on the plane of the section.(J.V.Maddox),LM bright field micrograph of Nosema bambycis in the silkworm Bombyx mori(家蚕).Binary fission of a meront in B.mori tissue culture.Giemsa stain.(R.Ishihara),Sporogonic Cycle TEM of the moniliform sporogonial plasmodium of Endoreticulatus fidelis from Leptinotarsa decemlineata(马铃薯叶甲).(J.J.Becnel),TEM of Amblyospora connecticus from the mosquito Aedes cantator.Early binucleare sporont within a sporophorous vesicle.(T.G.Andreadis),TEM of Amblyospora connecticus from the mosquito Aedes cantator.Sporogonal plasmodium within a spouophorous vesicle.(T.G.Andreadis),LM bright field micrograph of sporogonial stages of Nosema bombycis in the silkworm Bombyx mori.Sporonts are stained weakly and have white spots.Giemsa stain.(R.Ishihara),LM bright field micrograph of Amblyospora californica from Culex tarsalis.Developmental stages during the sporulation sequence involving meiosis.LAO stain.(J.J.Becnel),LM bright field microhraph of Amblyospora californica from Culex tarsalis.Developmental stages during the sporulation sequence involving meiosis.Giemsa stain.(J.J.Becnel),Infected Hosts,Fourth instar,fat body infection of Aedes aegypti by Edhazardia aedis.Infection is expressed as porcelain-white cysts in the thoracic fat body.(J.J.Becnel),Navel orangeworm,Amyelois transitella(脐橙蛾),larvae infected with Vairimorpha heterosporium.Large,healthy control larvae at left,and stunted,infected larvae at right.Four weeks post infection.(W.Kellen),Navel orangeworm,Amyelois transitella,pupae infected with Vairimorpha heterosporium.Large,healthy control pupae at left,and stunted and deformed infected pupae at right.(W.Kellen),Cell Division and Life Cycle,Modes of cell division that occur in microsporidian.Redrawn from LARSSON,1986.(Progress in Protistology,Vol.1,325-390)(J.V.Maddox),Diagrammatic representation of a microsporidian life cycle in which all stages gave isolated haplokaryotic nuclei.Redrawn from Larsson,1986.(Progress in Protistology,Vol.1,325-390)(J.V.Maddox),Diagrammatic repre-sentation of a micro-sporidian life cycle in which all stages have diplokaryotic(paired)nuclei.Redrawn from Larsson,1986.(Progress in Protistology,Vol.1,325-390)(J.V.Maddox),三、昆虫微孢子虫及其应用,微孢子虫种类和寄主范围致病机理微孢子虫的存活与环境条件的关系微孢子虫的传播微孢子虫的人工繁殖微孢子虫的应用,微孢子虫种类和寄主范围,微孢子虫门微孢子纲微孢子虫目种类：800种以上寄主范围较广：400种以上的昆虫，一般一种微孢子虫可侵染同一科的数种昆虫，有的科侵染数科甚至数目的昆虫感染时期：从卵到成虫的任何时期,致病机理,侵染过程：微孢子虫的成熟孢子被昆虫取食后在寄主消化道内发芽。在孢子活化过程中，孢子内盘曲的极丝通过极帽而迅速翻出，极丝穿过寄主肠道的围食膜，刺进肠壁细胞，紧接着胞质沿着极丝管腔被压出，注入寄主细胞内。不同种类的微孢子虫侵染寄主的不同器官：消化道、脂肪体、马氏管、神经节,致病机理,致病机理：由于微孢子虫在寄主细胞中大量增殖，堆积和机械挤压作用，使细胞内的内质网、线粒体、细胞核等细胞器受到严重破坏，细胞的代谢功能严重受损，最后导致细胞破碎死亡，这一过程逐渐扩大至寄主的整个组织或整个器官，使其功能丧失，从而导致寄主死亡。微孢子虫侵入幼虫神经节外层，引起神经节的病理组织变化，导致幼虫急性瘫痪。,微孢子虫的存活与环境条件的关系,温度：昆虫取食的温度范围光照湿度 高温、低温、紫外光照射和干旱都会对微孢子虫孢子的存活产生抑制作用,微孢子虫的传播,水平传播：经由某种媒介物作为污染源在种群内不同个体间进行传播 影响因素：宿主密度、幼虫的发育期、低龄幼虫的死亡率垂直传播：孢子通过雌成虫的卵传给下一代，使下一代幼虫受到侵染,微孢子虫的人工繁殖,活体培养 亚洲玉米螟微孢子虫昆虫细胞系离体培养 蝗虫微孢子虫,微孢子虫的应用,按蚊微孢子虫防治蚊虫 对按蚊、伊蚊和库蚊等27种蚊子有致病性，可使其大量死亡，幸存的成虫产卵量减少，寿命缩短，传播疟疾等疾病的能力降低。枞色卷蛾微孢子虫防治杉树卷蛾 可引起慢性、衰弱的病症，患病的雌蛾可以经卵传染给下一代,TEM of Amblyospora connecticusaa(钝孢子虫属)from the mosquito Aedes cantator.This binucleate spore,from the ovary of an adult female,is responsible for transmitting the infection from the female to the egg.Note two nuclei,polaroplast,isofilar polar filament and posterior vacuole.(T.G.Andreadis),TEM of Amblyospora connecticus from the mosquito Aedes cantator.This meiospore from the fat body of a larval mosquito is responsible for transmission to the intermediate copepod host.Note single nucleus,polaroplast,anchoring disc,an isofilar polar filament,and posterior vacuole.(T.G.Andreadis),微孢子虫的应用,蝗虫微孢子虫防治蝗虫 若虫发育延缓，患病严重的食量减少，常显畸形，翅足扭曲，前肠伸出，产卵量减少玉米螟微孢子虫防治玉米螟,TEM of Nosema pyrausta(玉米螟微孢子虫)from the European corn borer,Ostrinia nubilalis.A diplo-karyotic immature environmental spore from the salivary gland of a European corn borer larva.This spore is responsible for horizontal transmission from an infected corn borer larva to a susceptible larva.(J.V.Maddox),TEM of Culicospora magna from the mosquito Culex restuans.A uninucleate spore illustrating the compartmentalized and vacuolated polaroplast with an isofilar polar filament.(J.J.Becnel),第六节 微生物杀菌剂及除草剂,主要内容,一、微生物杀菌剂二、微生物除草剂,一、微生物杀菌剂,1.细 菌1)革兰氏阴性细菌假单孢菌(荧光假单孢菌)、放射性土壤杆菌、欧文菌(欧氏杆菌)2)革兰氏阳性菌芽孢杆菌(蜡质芽孢杆菌、枯草芽孢杆菌),一、微生物杀菌剂,2.真菌1)木霉菌(哈茨木霉、绿色木霉、钩状木霉、长枝木霉、康氏木霉、绿黏帚霉)2)蜡蚧轮枝孢,一、微生物杀菌剂,3.放线菌链霉菌4.病毒的弱毒株系(或RNA防治病毒病),二、微生物除草剂,1.定义 在人为控制下施用的杀灭杂草的人工培养的大剂量微生物制剂，使目标杂草感病致死，是一类防除特定杂草的生物制品。,二、微生物除草剂,2.微生物控制杂草的策略传统的或预防的淹没式的或大规模的应用3.微生物除草剂品种专性寄生真菌、土生病原真菌、非植物致病性真菌、细菌和线虫,活体微生物除草剂盘长孢状刺盘孢棕榈疫霉菌极毛杆菌黄杆菌黑腐病菌、克芽孢杆菌、保鲁一号(专性寄生菟丝子的真菌),作业,名词解释 水平传播问答题 你认为微孢子虫能作为一类重要的微生物杀虫剂吗？为什么？,