小菜蛾幼虫中肠细菌的分离鉴定夏晓峰1,2，郑丹丹1，林海兰1，尤.DOC

小菜蛾幼虫中肠细菌的分离鉴定 夏晓峰1, 2， 郑丹丹1， 1， 尤民生1 福建农林大学应用生态研究所，福州 350002福州市疾病预防控制中心，福州，350004 摘要 昆虫中肠微生物在其食物消化、生长发育以及抵御病原菌等方面都具有重要作用。为了深入研究小菜蛾Plutella xylostella (L.)幼虫中肠微生物的群落结构组成和功能，本文利用传统的微生物培养方法从饲养的小菜蛾3龄幼虫中肠分离得到8株细菌，经16S rDNA分子鉴定，分属于Serratia（3株），Enterobacter（3株），Stenotrophomonas（1株）和Myroides（1株）4个属，与分离自污水、土壤、植物、白蚁和甜菜夜蛾肠道以及人类肠道中的细菌具有很高的同源性，其中，7株菌均归类于γ-变形菌门gamma-proteobacteria，表明小菜蛾幼虫中肠可培养细菌的优势菌群为gamma-proteobacteria。本研究为进一步探讨小菜蛾中肠细菌的群落结构及其功能提供了菌株材料和工作基础。 关键词 小菜蛾；中肠；细菌；16S rDNA；γ-变形菌门 Isolation and identification of bacteria from the larval midgut of diamondback moth, Plutella xylostella (L.) XIA Xiao-Feng 1,2, ZHENG Dan-Dan 1, LIN Hai-Lan 1, YOU Min-Sheng 1*, (1.Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; 2. Fuzhou Center for Disease Control and Prevention, Fuzhou, 350004, China) Abstract: Microbiota inhabiting in insect midguts play important roles in food digestion, development of insects, and even preventing from infestation by pathogens. In order to study the composition, structure and function of bacteria in the midgut of diamondback moth (DBM), Plutella xylostella (L.), eight strains of bacteria were isolated from the 3rd-instar larval midgut using the traditional culture method . These bacteria were classified into four genus of Serratia(3 strains), Enterobacter(3 strains), Stenotrophomonas(1 strain) and Myroides(1 strain) identified by 16S rDNA sequence, and seven strains were identified to be the phylum of gamma-proteobacteria, indicating that the DBM larval midgut may be dominated by this taxon of bacteria. Our work provides a foundation for further studies on the structure and function of microbiota in the DBM larval midgut. Keywords: Plutella xylostella； midgut； bacteria； 16S rDNA； gamma-proteobacteria 小菜蛾(Plutella xylostella (L.))是危害十字花科蔬菜的世界性害虫，可取食甘蓝、大白菜、萝卜等经济作物，造成严重的经济损失。农药的大量使用致使小菜蛾对所有的杀虫剂，包括生物农药Bt均产生了抗性，每年由小菜蛾引起的产量损失和防治费用高达10亿美元以上( Talekar and Shelton, 1993)。 目前，对小菜蛾的研究主要集中在其生物学和生态学( Wakisaka et al.，199