title: Mediation of pathogen resistance by exudation of antimicrobials from roots.
abstract: Most plant species are resistant to most potential pathogens. It is not known why most plant-microbe interactions do not lead to disease, although recent work indicates that this basic disease resistance is multi-factorial. Here we show that the exudation of root-derived antimicrobial metabolites by Arabidopsis thaliana confers tissue-specific resistance to a wide range of bacterial pathogens. However, a Pseudomonas syringae strain that is both at least partly resistant to these compounds and capable of blocking their synthesis/exudation is able to infect the roots and cause disease. We also show that the ability of this P. syringae strain to block antimicrobial exudation is dependent on the type III secretory system.
authors.affiliation: Department of Horticulture and Landscape Architecture, and Center for Rhizosphere Biology, Colorado State University, Fort Collins, Colorado 80523-1173, USA.
authors.forename: Harsh P
authors.initials: HP
authors.lastname: Bais
authors.forename: Balakrishnan
authors.initials: B
authors.lastname: Prithiviraj
authors.forename: Ajay K
authors.initials: AK
authors.lastname: Jha
authors.forename: Frederick M
authors.initials: FM
authors.lastname: Ausubel
authors.forename: Jorge M
authors.initials: JM
authors.lastname: Vivanco
mesh_terms: D000890:Anti-Infective Agents / Q000378:metabolism*; D017360:Arabidopsis / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology*; D020148:Butyric Acid / Q000378:metabolism; D002606:Charcoal; D007700:Kinetics; D009928:Organ Specificity; D010935:Plant Diseases / Q000382:microbiology*; D018517:Plant Roots / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology*; D044224:Pseudomonas syringae / Q000145:classification / Q000472:pathogenicity / Q000502:physiology; D014774:Virulence
chemical_list: D000890:Anti-Infective Agents; D020148:Butyric Acid; D002606:Charcoal