title: Broad-spectrum acquired resistance in barley induced by the Pseudomonas pathosystem shares transcriptional components with Arabidopsis systemic acquired resistance.
abstract: Inducible resistance responses play a central role in the defense of plants against pathogen attack. Acquired resistance (AR) is induced alongside defense toward primary attack, providing broad-spectrum protection against subsequent pathogen challenge. The localization and molecular basis of AR in cereals is poorly understood, in contrast with the well-characterized systemic acquired resistance (SAR) response in Arabidopsis. Here, we use Pseudomonas syringae as a biological inducer of AR in barley, providing a clear frame of reference to the Arabidopsis-P. syringae pathosystem. Inoculation of barley leaf tissue with the nonadapted P. syringae pv. tomato avrRpm1 (PstavrRpm1) induced an active local defense response. Furthermore, inoculation of barley with PstavrRpm1 resulted in the induction of broad-spectrum AR at a distance from the local lesion, "adjacent" AR, effective against compatible isolates of P. syringae and Magnaporthe oryzae. Global transcriptional profiling of this adjacent AR revealed similarities with the transcriptional profile of SAR in Arabidopsis, as well as transcripts previously associated with chemically induced AR in cereals, suggesting that AR in barley and SAR in Arabidopsis may be mediated by analogous pathways.
authors.affiliation: Department of Disease and Stress Biology, John Innes Centre, Norwich Research Park, Norwich, Norfolk, NR4 7UH, UK. ellen.colebrook@rothamsted.ac.uk
authors.forename: E H
authors.initials: EH
authors.lastname: Colebrook
authors.forename: G
authors.initials: G
authors.lastname: Creissen
authors.forename: G R D
authors.initials: GR
authors.lastname: McGrann
authors.forename: R
authors.initials: R
authors.lastname: Dreos
authors.forename: C
authors.initials: C
authors.lastname: Lamb
authors.forename: L A
authors.initials: LA
authors.lastname: Boyd
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D016000:Cluster Analysis; D060467:Disease Resistance / Q000235:genetics / Q000502:physiology*; D015536:Down-Regulation / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D001467:Hordeum / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D054884:Host-Pathogen Interactions; D020082:Magnaporthe / Q000254:growth & development*; D020411:Oligonucleotide Array Sequence Analysis; D018515:Plant Leaves / Q000276:immunology / Q000382:microbiology; D044224:Pseudomonas syringae / Q000254:growth & development* / Q000276:immunology; D036226:Seedlings / Q000382:microbiology; D059467:Transcriptome / Q000235:genetics*; D015854:Up-Regulation / Q000235:genetics