title: Stimulation of the Salicylic Acid Pathway Aboveground Recruits Entomopathogenic Nematodes Belowground.
abstract: Plant defense pathways play a critical role in mediating tritrophic interactions between plants, herbivores, and natural enemies. While the impact of plant defense pathway stimulation on natural enemies has been extensively explored aboveground, belowground ramifications of plant defense pathway stimulation are equally important in regulating subterranean pests and still require more attention. Here we investigate the effect of aboveground stimulation of the salicylic acid pathway through foliar application of the elicitor methyl salicylate on belowground recruitment of the entomopathogenic nematode, Steinernema diaprepesi. Also, we implicate a specific root-derived volatile that attracts S. diaprepesi belowground following aboveground plant stimulation by an elicitor. In four-choice olfactometer assays, citrus plants treated with foliar applications of methyl salicylate recruited S. diaprepesi in the absence of weevil feeding as compared with negative controls. Additionally, analysis of root volatile profiles of citrus plants receiving foliar application of methyl salicylate revealed production of d-limonene, which was absent in negative controls. The entomopathogenic nematode S. diaprepesi was recruited to d-limonene in two-choice olfactometer trials. These results reinforce the critical role of plant defense pathways in mediating tritrophic interactions, suggest a broad role for plant defense pathway signaling belowground, and hint at sophisticated plant responses to pest complexes.
authors.affiliation: Department of Entomology, Universidade Federal de Lavras, Lavras, MG, Brazil.
authors.forename: Camila Cramer
authors.initials: CC
authors.lastname: Filgueiras
authors.affiliation: Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America.
authors.forename: Denis S
authors.initials: DS
authors.lastname: Willett
authors.affiliation: Department of Entomology, Universidade Federal de Lavras, Lavras, MG, Brazil.
authors.forename: Alcides Moino
authors.initials: AM
authors.lastname: Junior
authors.affiliation: Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas - UNICAMP, Campinas, SP, Brazil.
authors.forename: Martin
authors.initials: M
authors.lastname: Pareja
authors.affiliation: Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America.|Plant Protection Department, Faculty of Agriculture, Zagazig University, Sharkia, Egypt.
authors.forename: Fahiem El
authors.initials: FE
authors.lastname: Borai
authors.affiliation: Entomology and Nematology Department, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Donald W
authors.initials: DW
authors.lastname: Dickson
authors.affiliation: Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America.
authors.forename: Lukasz L
authors.initials: LL
authors.lastname: Stelinski
authors.affiliation: Entomology and Nematology Department, Citrus Research and Education Center, University of Florida, Lake Alfred, Florida, United States of America.
authors.forename: Larry W
authors.initials: LW
authors.lastname: Duncan
mesh_terms: D000818:Animals; D001681:Biological Assay; D020387:Food Chain; D060434:Herbivory / Q000187:drug effects; D018517:Plant Roots / Q000378:metabolism; D017168:Rhabditida / Q000187:drug effects*; D012459:Salicylates / Q000378:metabolism / Q000494:pharmacology*; D055549:Volatile Organic Compounds / Q000378:metabolism
chemical_list: D012459:Salicylates; D055549:Volatile Organic Compounds; C033069:methyl salicylate