玫烟色棒束孢侵染小菜蛾的透射电镜观察  

Observation of infection process of Isaria fumosorosea to Plutella xylostella with transmission electron microscopy

作　　者：雷妍圆[1,2] 何余容[1] 吕利华[3] 

机构地区：[1]华南农业大学资源环境学院,广州510642 [2]中国农业科学院蔬菜花卉研究所,北京100081 [3]广东省农业科学院植物保护研究所,广州510640

出　　处：《应用昆虫学报》2011年第2期319-323,共5页Chinese Journal of Applied Entomology

基　　金：公益性行业(农业)科研专项(201103025);广东省农业攻关项目(2006B20301037)

摘　　要：利用透射电镜观察了玫烟色棒束孢Isaria fumosorosea(=Paecilomyces fumosoroseus)对小菜蛾Plutella xylostella(L.)的侵染过程及菌体在虫体内的增殖方式。以浓度为1×107孢子/mL的孢子悬浮液接种小菜蛾4龄幼虫,在透射电镜下对虫体各部位的观察结果表明:接种后1h玫烟色棒束孢菌株EBCL03011的分生孢子开始萌芽,至4h可观察到附着孢的形成和穿透,接种后24h已普遍侵入体腔。玫烟色棒束孢在寄主表皮和体腔内,以菌丝段出芽生殖、菌丝分隔及菌丝段分隔3种方式大量增殖,主要以颗粒状的菌丝段在寄主体腔内扩散,菌丝段在穿透表皮和体腔内增殖过程中伴随着机械压力和酶的活动。To demonstrate the process of infection of Plutella xylostella（L.）（Lepidoptera：Plutellidae） by the indigenous strain EBCL 03011 of the fungus Isaria fumosorosea（= Paecilomyces fumosoroseus）（Hypocreales：Cordycipitaceae） 4th instar larvae of P.xylostella were experimentally infected with a fungal suspension（1 × 107 conidia / mL） and organs such as the integument,mid-gut and muscle tissues subsequently examined by transmission electron microscopy.Histopathological analyses revealed that conidia of I.fumosorosea germinated 1 h post-inoculation resulting in appresorium formation ultimately penetrating the integument of P.xylostella 4 h after inoculation.The hyphal bodies had spread into the body cavity 24 h after inoculation.The penetrating hyphae of I.fumosorosea produced a number of granular hyphal bodies by budding or septation,and became distributed throughout the cuticle and hemocoel of the infected larvae.The penetration and propagation of the hyphal bodies was achieved by a combination of mechanical pressure and enzymatic action during the infection process.

关 键 词：小菜蛾 玫烟色棒束孢 侵染过程 增殖方式 透射电镜 

分 类 号：S476.1[农业科学—农业昆虫与害虫防治]