title: Volatile communication between plants that affects herbivory: a meta-analysis.
abstract: Volatile communication between plants causing enhanced defence has been controversial. Early studies were not replicated, and influential reviews questioned the validity of the phenomenon. We collected 48 well-replicated studies and found overall support for the hypothesis that resistance increased for individuals with damaged neighbours. Laboratory or greenhouse studies and those conducted on agricultural crops showed stronger induced resistance than field studies on undomesticated species, presumably because other variation had been reduced. A cumulative analysis revealed that early, non-replicated studies were more variable and showed less evidence for communication. Effects of habitat and plant growth form were undetectable. In most cases, the mechanisms of resistance and alternative hypotheses were not considered. There was no indication that some response variables were more likely to produce large effects. These results indicate that plants of diverse taxonomic affinities and ecological conditions become more resistant to herbivores when exposed to volatiles from damaged neighbours.
authors.affiliation: Department of Entomology, University of California, Davis, CA, 95616, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Karban
authors.forename: Louie H
authors.initials: LH
authors.lastname: Yang
authors.forename: Kyle F
authors.initials: KF
authors.lastname: Edwards
mesh_terms: D060434:Herbivory; D010675:Pheromones; D018521:Plant Physiological Phenomena; D010944:Plants; D055549:Volatile Organic Compounds
chemical_list: D010675:Pheromones; D055549:Volatile Organic Compounds
keywords: Eavesdropping; induced resistance; plant behaviour; plant signalling; volatiles