蕙兰病株根部内生细菌种群变化  

Population dynamics of endophytic bacteria isolated from the roots of infected Cymbidium faberi

作　　者：杨娜[1,2] 杨波[1] 

机构地区：[1]中国科学院武汉植物园中国科学院植物种质创新与特色农业重点实验室,武汉430074 [2]中国科学院研究生院,北京100049

出　　处：《生态学报》2011年第5期1203-1212,共10页Acta Ecologica Sinica

基　　金：中国科学院创新专项(KSCX2-YW-Z-0702-5)

摘　　要：为了研究褐斑病与蕙兰根部内生细菌群落结构和多样性的关联,从野生蕙兰健株和褐斑病株根部分离出内生细菌112株,采用核糖体DNA扩增片段限制性酶切分析(ARDRA),研究了健株和病株内生细菌多样性与群落结构。将内生细菌纯培养物扩增近全长的16S rDNA,并用ARDRA(Amplified Ribosomal DNA Restriction Analysis)对所分离的菌株进行分型,根据酶切图谱的差异,将健株中的内生细菌分成8个ARDRA型,病株分成13个ARDRA型。并选取代表性菌株进行16S rDNA序列测定。结果表明,健株分离出内生细菌6个属,优势菌群为Bacillus;病株分离出11个属,优势菌群为Mitsuaria和Flavobacterium。通过回接兰花植物和初步拮抗实验发现,从病株分离出的H5号菌株(Flavobacterium resistens)使兰花产生病症,而健株中的B02(Bacillus cereus)和B22号菌株(Burkholderia stabilis)对菌株H5有拮抗作用。A study was conducted to investigate the community structure and the diversity of culturable endophytic bacteria in the root tissues of healthy and diseased plants of Cumbidium faberi Rolfe collected from Hubei Province of China.The endophytic bacteria were identified by characterization of cultural features,and some molecular features using methods of amplified ribosomal DNA restriction analysis（ARDRA） and sequence homology comparisons.Results showed that a total of 112 bacterial isolates were obtained,53 strains from healthy plants and 59 strains from diseased plants of C.faberi.The amount of bacteria reached 1.33×105 cfu/g in healthy plants,whereas was 1.21×104 cfu/g in the plants infected with brown spot disease.The number of endophytic bacteria decreased in the diseased plants.Comparison of the AluI-restriction patterns of the 16S rDNA sequence showed that 112 bacterial isolates from diseased plants could be grouped into 13 operational taxonomic units（OTUs）.The OTU10 and OTU11 were the major groups accounting for 13 and15 isolates,respectively.The bacterial isolates from healthy plants could be grouped into 8 OTUs and OTU1 was the major group accounting for 24 isolates.The representative strains for these OUTs were selected for characterization of the 16S rDNA sequences.Phylogenetic analysis on the basis of the 16S rDNA sequences from this study and from related bacterial species in the GenBank database showed that the representative bacterial isolates from the healthy plants of C.faberi belonged to six genera,Bacillus,Rhizobium,Burkholderia,Paenibacillus,Pseudomonas and Microbacterium.The genus Bacillus was the dominant bacteria,followed by Paenibacillus and Burkholderia.The bacterial isolates from diseased plants of C.faberi belonged to eleven genera,Mitsuaria,Flavobacterium,Bacillus,Enterobacter,Brevundimonas,Pedobacter,Burkholderia,Sphingomonas,Mucilaginibacter,Pseudomonas and Microbacterium.The dominant genera were Mitsuaria and Flavobacterium,followed by Burkholderia.The phylogenetic diversit

关 键 词：蕙兰 内生细菌 群落结构 ARDRA 16S RDNA 

分 类 号：S436.8[农业科学—农业昆虫与害虫防治] Q93[农业科学—植物保护]