title: Pseudomonas syringae enhances herbivory by suppressing the reactive oxygen burst in Arabidopsis.
abstract: Plant-herbivore interactions have evolved in the presence of plant-colonizing microbes. These microbes can have important third-party effects on herbivore ecology, as exemplified by drosophilid flies that evolved from ancestors feeding on plant-associated microbes. Leaf-mining flies in the genus Scaptomyza, which is nested within the paraphyletic genus Drosophila, show strong associations with bacteria in the genus Pseudomonas, including Pseudomonas syringae. Adult females are capable of vectoring these bacteria between plants and larvae show a preference for feeding on P. syringae-infected leaves. Here we show that Scaptomyza flava larvae can also vector P. syringae to and from feeding sites, and that they not only feed more, but also develop faster on plants previously infected with P. syringae. Our genetic and physiological data show that P. syringae enhances S. flava feeding on infected plants at least in part by suppressing anti-herbivore defenses mediated by reactive oxygen species.
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, United States; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States. Electronic address: scgroen@email.arizona.edu.
authors.forename: Simon C
authors.initials: SC
authors.lastname: Groen
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, United States. Electronic address: pth@email.arizona.edu.
authors.forename: Parris T
authors.initials: PT
authors.lastname: Humphrey
authors.affiliation: Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States. Electronic address: daniela578@gmail.com.
authors.forename: Daniela
authors.initials: D
authors.lastname: Chevasco
authors.affiliation: Department of Genetics, Harvard Medical School, Boston, MA 02115, United States; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, United States. Electronic address: ausubel@molbio.mgh.harvard.edu.
authors.forename: Frederick M
authors.initials: FM
authors.lastname: Ausubel
authors.affiliation: Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States. Electronic address: npierce@oeb.harvard.edu.
authors.forename: Naomi E
authors.initials: NE
authors.lastname: Pierce
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, United States; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, United States. Electronic address: whiteman@email.arizona.edu.
authors.forename: Noah K
authors.initials: NK
authors.lastname: Whiteman
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000276:immunology / Q000382:microbiology / Q000469:parasitology*; D018428:Drosophilidae / Q000382:microbiology / Q000502:physiology*; D060434:Herbivory; D006790:Host-Parasite Interactions; D057865:Plant Immunity; D044224:Pseudomonas syringae / Q000502:physiology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013559:Symbiosis
chemical_list: D017382:Reactive Oxygen Species
keywords: Arabidopsis thaliana; Drosophila melanogaster; Herbivore; Plant defense; Pseudomonas syringae; Reactive oxygen species; Scaptomyza