title: Early herbivore alert matters: plant-mediated effects of egg deposition on higher trophic levels benefit plant fitness.
abstract: Induction of plant defences, specifically in response to herbivore attack, can save costs that would otherwise be needed to maintain defences even in the absence of herbivores. However, plants may suffer considerable damage during the time required to mount these defences against an attacker. This could be resolved if plants could respond to early cues, such as egg deposition, that reliably indicate future herbivory. We tested this hypothesis in a field experiment and found that egg deposition by the butterfly Pieris brassicae on black mustard (Brassica nigra) induced a plant response that negatively affected feeding caterpillars. The effect cascaded up to the third and fourth trophic levels (larval parasitoids and hyperparasitoids) by affecting the parasitisation rate and parasitoid performance. Overall, the defences induced by egg deposition had a positive effect on plant seed production and may therefore play an important role in the evolution of plant resistance to herbivores.
authors.affiliation: Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700AA, Wageningen, The Netherlands.|Institute of Agricultural Sciences, Biocommunication & Entomology, ETH Zürich, 8092, Zürich, Switzerland.
authors.forename: Foteini G
authors.initials: FG
authors.lastname: Pashalidou
authors.affiliation: Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700AA, Wageningen, The Netherlands.
authors.forename: Enric
authors.initials: E
authors.lastname: Frago
authors.affiliation: Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700AA, Wageningen, The Netherlands.|Institute of Biology, Dahlem Centre of Plant Sciences, Freie Universität Berlin, 12163, Berlin, Germany.
authors.forename: Eddie
authors.initials: E
authors.lastname: Griese
authors.affiliation: Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700AA, Wageningen, The Netherlands.
authors.forename: Erik H
authors.initials: EH
authors.lastname: Poelman
authors.affiliation: Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700AA, Wageningen, The Netherlands.
authors.forename: Joop J A
authors.initials: JJ
authors.lastname: van Loon
authors.affiliation: Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700AA, Wageningen, The Netherlands.
authors.forename: Marcel
authors.initials: M
authors.lastname: Dicke
authors.affiliation: Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700AA, Wageningen, The Netherlands.|Institute of Biology, Dahlem Centre of Plant Sciences, Freie Universität Berlin, 12163, Berlin, Germany.
authors.forename: Nina E
authors.initials: NE
authors.lastname: Fatouros
mesh_terms: D000097:Acetonitriles / Q000494:pharmacology; D000818:Animals; D001937:Brassica / Q000235:genetics / Q000502:physiology*; D002080:Butterflies / Q000502:physiology*; D005260:Female; D056084:Genetic Fitness; D018525:Germination; D060434:Herbivory; D007814:Larva; D010058:Oviposition; D012639:Seeds / Q000502:physiology
chemical_list: D000097:Acetonitriles; C006725:benzyl cyanide
keywords: Brassica; community ecology; induced direct and indirect plant defences; multitrophic interactions; parasitoids; trait-mediated interactions