title: Rhizosphere bacterial communities associated with disease suppressiveness stages of take-all decline in wheat monoculture.
abstract: The decline of take-all disease (Gaeumannomyces graminis var. tritici), which may take place during wheat monocropping, involves plant-protecting, root-colonizing microorganisms. So far, however, most work has focused on antagonistic fluorescent pseudomonads. Our objective was to assess the changes in rhizobacterial community composition during take-all decline of field-grown wheat. The study was based on the development and utilization of a taxonomic 16S rRNA-based microarray of 575 probes, coupled with cloning-sequencing and quantitative PCR. Plots from one experimental field grown with wheat for 1 yr (low level of disease), 5 yr (high level of disease) or 10 yr (low level of disease, suppressiveness reached) were used. Microarray data discriminated between the three stages. The outbreak stage (5 yr) was mainly characterized by the prevalence of Proteobacteria, notably Pseudomonas (Gammaproteobacteria), Nitrosospira (Betaproteobacteria), Rhizobacteriaceae, Sphingomonadaceae, Phyllobacteriaceae (Alphaproteobacteria), as well as Bacteroidetes and Verrucomicrobia. By contrast, suppressiveness (10 yr) correlated with the prevalence of a broader range of taxa, which belonged mainly to Acidobacteria, Planctomycetes, Nitrospira, Chloroflexi, Alphaproteobacteria (notably Azospirillum) and Firmicutes (notably Thermoanaerobacter). In conclusion, take-all decline correlated with multiple changes in rhizobacterial community composition, far beyond the sole case of pseudomonads.
authors.affiliation: Université de Lyon, F-69003, Lyon, France.|Université Lyon 1, F-69003 Villeurbanne, France.|CNRS, UMR5557, Ecologie Microbienne, F-69622 Villeurbanne, France.
authors.forename: H
authors.initials: H
authors.lastname: Sanguin
authors.affiliation: INRA, Agrocampus Ouest, Université Rennes 1, UMR 1099 BiO3P 'Biologie des Organismes et des Populations appliquée à la Protection des Plantes', F-35653 Le Rheu, France.
authors.forename: A
authors.initials: A
authors.lastname: Sarniguet
authors.affiliation: INRA, Agrocampus Ouest, Université Rennes 1, UMR 1099 BiO3P 'Biologie des Organismes et des Populations appliquée à la Protection des Plantes', F-35653 Le Rheu, France.
authors.forename: K
authors.initials: K
authors.lastname: Gazengel
authors.affiliation: Université de Lyon, F-69003, Lyon, France.|Université Lyon 1, F-69003 Villeurbanne, France.|CNRS, UMR5557, Ecologie Microbienne, F-69622 Villeurbanne, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Moënne-Loccoz
authors.affiliation: Université de Lyon, F-69003, Lyon, France.|Université Lyon 1, F-69003 Villeurbanne, France.|CNRS, UMR5557, Ecologie Microbienne, F-69622 Villeurbanne, France.
authors.forename: G L
authors.initials: GL
authors.lastname: Grundmann
mesh_terms: D001203:Ascomycota / Q000472:pathogenicity*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D018407:Bacterial Physiological Phenomena; D017753:Ecosystem; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology* / Q000517:prevention & control*; D018517:Plant Roots / Q000382:microbiology; D011548:Pseudomonadaceae / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology; D013045:Species Specificity; D013559:Symbiosis; D014908:Triticum / Q000254:growth & development* / Q000382:microbiology*
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S