Maria Buerstmayr1, Christian Wagner2, Tetyana Nosenko3,4, Jimmy Omony3,5, Barbara Steiner2, Thomas Nussbaumer6,7, Klaus F X Mayer3, Hermann Buerstmayr2. 1. University of Natural Resources and Life Sciences, Austria, Department of Agrobiotechnology - IFA Tulln, Institute of Biotechnology in Plant Production, Konrad Lorenz Str 20, Tulln, Austria. maria.buerstmayr@boku.ac.at. 2. University of Natural Resources and Life Sciences, Austria, Department of Agrobiotechnology - IFA Tulln, Institute of Biotechnology in Plant Production, Konrad Lorenz Str 20, Tulln, Austria. 3. Helmholtz Zentrum München, Germany, PGSB Plant Genome and Systems Biology, German Research Center for Environmental Health, Neuherberg, Germany. 4. Helmholtz Zentrum München, Germany, Research Unit Environmental Simulation (EUS) at the Institute of Biochemical Plant Pathology (BIOP), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany. 5. Helmholtz Zentrum München, Germany, Institut für Asthma- und Allergieprävention (IAP), Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Munich, Germany. 6. Helmholtz Zentrum München, Germany, Institute of Network Biology (INET), Ingolstädter Landstraße 1, 85764, Neuherberg, Germany. 7. Helmholtz Zentrum München, Germany, Institute of Environmental Medicine UNIKA-T, Technical University and Helmholtz Zentrum München, Augsburg, Germany.
Abstract
BACKGROUND: Fusarium head blight (FHB) is a devastating disease of wheat worldwide. Resistance to FHB is quantitatively controlled by the combined effects of many small to medium effect QTL. Flowering traits, especially the extent of extruded anthers, are strongly associated with FHB resistance. RESULTS: To characterize the genetic basis of FHB resistance, we generated and analyzed phenotypic and gene expression data on the response to Fusarium graminearum (Fg) infection in 96 European winter wheat genotypes, including several lines containing introgressions from the highly resistant Asian cultivar Sumai3. The 96 lines represented a broad range in FHB resistance and were assigned to sub-groups based on their phenotypic FHB severity score. Comparative analyses were conducted to connect sub-group-specific expression profiles in response to Fg infection with FHB resistance level. Collectively, over 12,300 wheat genes were Fusarium responsive. The core set of genes induced in response to Fg was common across different resistance groups, indicating that the activation of basal defense response mechanisms was largely independent of the resistance level of the wheat line. Fg-induced genes tended to have higher expression levels in more susceptible genotypes. Compared to the more susceptible non-Sumai3 lines, the Sumai3-derivatives demonstrated higher constitutive expression of genes associated with cell wall and plant-type secondary cell wall biogenesis and higher constitutive and Fg-induced expression of genes involved in terpene metabolism. Gene expression analysis of the FHB QTL Qfhs.ifa-5A identified a constitutively expressed gene encoding a stress response NST1-like protein (TraesCS5A01G211300LC) as a candidate gene for FHB resistance. NST1 genes are key regulators of secondary cell wall biosynthesis in anther endothecium cells. Whether the stress response NST1-like gene affects anther extrusion, thereby affecting FHB resistance, needs further investigation. CONCLUSION: Induced and preexisting cell wall components and terpene metabolites contribute to resistance and limit fungal colonization early on. In contrast, excessive gene expression directs plant defense response towards programmed cell death which favors necrotrophic growth of the Fg pathogen and could thus lead to increased fungal colonization.
BACKGROUND:Fusarium head blight (FHB) is a devastating disease of wheat worldwide. Resistance to FHB is quantitatively controlled by the combined effects of many small to medium effect QTL. Flowering traits, especially the extent of extruded anthers, are strongly associated with FHB resistance. RESULTS: To characterize the genetic basis of FHB resistance, we generated and analyzed phenotypic and gene expression data on the response to Fusarium graminearum (Fg) infection in 96 European winter wheat genotypes, including several lines containing introgressions from the highly resistant Asian cultivar Sumai3. The 96 lines represented a broad range in FHB resistance and were assigned to sub-groups based on their phenotypic FHB severity score. Comparative analyses were conducted to connect sub-group-specific expression profiles in response to Fginfection with FHB resistance level. Collectively, over 12,300 wheat genes were Fusarium responsive. The core set of genes induced in response to Fg was common across different resistance groups, indicating that the activation of basal defense response mechanisms was largely independent of the resistance level of the wheat line. Fg-induced genes tended to have higher expression levels in more susceptible genotypes. Compared to the more susceptible non-Sumai3 lines, the Sumai3-derivatives demonstrated higher constitutive expression of genes associated with cell wall and plant-type secondary cell wall biogenesis and higher constitutive and Fg-induced expression of genes involved in terpene metabolism. Gene expression analysis of the FHB QTL Qfhs.ifa-5A identified a constitutively expressed gene encoding a stress response NST1-like protein (TraesCS5A01G211300LC) as a candidate gene for FHB resistance. NST1 genes are key regulators of secondary cell wall biosynthesis in anther endothecium cells. Whether the stress response NST1-like gene affects anther extrusion, thereby affecting FHB resistance, needs further investigation. CONCLUSION: Induced and preexisting cell wall components and terpene metabolites contribute to resistance and limit fungal colonization early on. In contrast, excessive gene expression directs plant defense response towards programmed cell death which favors necrotrophic growth of the Fg pathogen and could thus lead to increased fungal colonization.
Authors: Mina Samad-Zamini; Wolfgang Schweiger; Thomas Nussbaumer; Klaus F X Mayer; Hermann Buerstmayr Journal: Plant Biotechnol J Date: 2017-04-21 Impact factor: 9.803