title: Plant-mediated pheromone emission by a hemipteran seed feeder increases the apparency of an unreliable but rewarding host.
abstract: The defensive chemistry and persistence of plant tissues determine their suitability and apparency - the likelihood of being discovered - to insect herbivores. As consumers of plant tissues with transient apparency, florivores and seed-feeders must frequently migrate between host plants to synchronize colonization with plant phenology. Aggregation pheromones could provide information-based solutions to finding ephemeral hosts, but little is known about plant-influenced variation in this form of chemical communication. Combining analytical chemistry, de novo synthesis and field ecology, we investigated the change in colonization of two sympatric host plants, Nicotiana attenuata and Nicotiana obtusifolia, which differ in apparency-related life history traits, by a heteropteran seed-feeder, Corimelaena extensa. We identified a novel pheromone released by C. extensa males - (5Z,8Z)-tetradeca-5,8-dienal - and performed field assays with the synthetic pheromone, showing that it stimulates the formation of feeding aggregations on the post-fire annual N. attenuata. Corimelaena extensa pheromone emission was 40-fold higher when feeding on N. attenuata compared with the perennial N. obtusifolia, as were adult fecundity and seed capsule content of the putative biosynthetic precursor, linoleic acid. Higher pheromone emission increases the apparency and colonization of the ephemeral, high-quality host N. attenuata. This plant-specific variation in insect signaling could facilitate host-finding by seed-feeders migrating between plant patches.
authors.affiliation: Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany.
authors.forename: Mariana A
authors.initials: MA
authors.lastname: Stanton
authors.affiliation: Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Preβler
authors.affiliation: Research Group Biosynthesis/NMR, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Paetz
authors.affiliation: Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Boland
authors.affiliation: Research Group Mass Spectrometry/Proteomics, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany.
authors.forename: Aleš
authors.initials: A
authors.lastname: Svatoš
authors.affiliation: Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany.
authors.forename: Ian T
authors.initials: IT
authors.lastname: Baldwin
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000818:Animals; D060434:Herbivory; D020062:Heteroptera / Q000502:physiology*; D019787:Linoleic Acid / Q000032:analysis; D008297:Male; D010675:Pheromones / Q000737:chemistry / Q000502:physiology*; D012639:Seeds / Q000502:physiology*; D013045:Species Specificity; D014026:Nicotiana / Q000502:physiology*; D055549:Volatile Organic Compounds / Q000032:analysis
chemical_list: D000447:Aldehydes; D010675:Pheromones; D055549:Volatile Organic Compounds; D019787:Linoleic Acid
keywords: Corimelaena extensa; Hemiptera; Nicotiana attenuata; aggregation pheromone; host plant location; phenotypic plasticity; plant apparency; plant defense