title: Priming of anti-herbivore defence in Nicotiana attenuata by insect oviposition: herbivore-specific effects.
abstract: Oviposition by Spodoptera exigua on Nicotiana attenuata primes plant defence against its larvae that consequently suffer reduced performance. To reveal whether this is a general response of tobacco to insect oviposition or species-specific, we investigated whether also Manduca sexta oviposition primes N. attenuata's anti-herbivore defence. The plant response to M. sexta and S. exigua oviposition overlapped in the egg-primed feeding-induced production of the phenylpropanoid caffeoylputrescine. While M. sexta larvae were unaffected in their performance, they showed a novel response to the oviposition-mediated plant changes: a reduced antimicrobial activity in their haemolymph. In a cross-resistance experiment, S. exigua larvae suffered reduced performance on M. sexta-oviposited plants like they did on S. exigua-oviposited plants. The M. sexta oviposition-mediated plant effects on the S. exigua larval performance and on M. sexta larval immunity required expression of the NaMyb8 transcription factor that is governing biosynthesis of phenylpropanoids such as caffeoylputrescine. Thus, NaMyb8-dependent defence traits mediate the effects that oviposition by both lepidopteran species exerts on the plant's anti-herbivore defence. These results suggest that oviposition by lepidopteran species on N. attenuata leaves may generally prime the feeding-induced production of certain plant defence compounds but that different herbivore species show different susceptibility to egg-primed plant effects.
authors.affiliation: Molecular Ecology, Dahlem Centre of Plant Sciences (DCPS), Institute of Biology, Freie Universität (FU) Berlin, Haderslebener Str. 9, 12163, Berlin, Germany.
authors.forename: Michele
authors.initials: M
authors.lastname: Bandoly
authors.affiliation: Molecular Ecology, Dahlem Centre of Plant Sciences (DCPS), Institute of Biology, Freie Universität (FU) Berlin, Haderslebener Str. 9, 12163, Berlin, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Grichnik
authors.affiliation: Applied Zoology/Animal Ecology, DCPS, Institute of Biology, FU Berlin, Haderslebener Str. 9, 12163, Berlin, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Hilker
authors.affiliation: Molecular Ecology, Dahlem Centre of Plant Sciences (DCPS), Institute of Biology, Freie Universität (FU) Berlin, Haderslebener Str. 9, 12163, Berlin, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Steppuhn
mesh_terms: D000818:Animals; D020868:Gene Silencing; D060434:Herbivory / Q000502:physiology*; D007814:Larva / Q000276:immunology; D018402:Manduca / Q000502:physiology*; D010058:Oviposition / Q000502:physiology*; D010940:Plant Proteins / Q000378:metabolism; D013045:Species Specificity; D018411:Spodoptera / Q000502:physiology*; D014026:Nicotiana / Q000276:immunology* / Q000469:parasitology*
chemical_list: D010940:Plant Proteins
keywords: Manduca sexta; Spodoptera exigua; herbivory; induced plant defence; phenolics; protease inhibitors