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See detailAphid responses to volatile cues from turnip plants (Brassica rapa) infested with phloem-feeding and chewing herbivores
Verheggen, François ULg; Haubruge, Eric ULg; De Moraes, Consuelo et al

in Arthropod-Plant Interactions (2013), 7(5), 567-577

Herbivore-induced plant volatiles provide foraging cues for herbivores and for herbivores’ natural enemies. Aphids induce plant volatile emissions and also utilize plant-derived olfactory volatile cues ... [more ▼]

Herbivore-induced plant volatiles provide foraging cues for herbivores and for herbivores’ natural enemies. Aphids induce plant volatile emissions and also utilize plant-derived olfactory volatile cues, but the chemical ecology of aphids and other phloem-feeding insects is less extensively documented than that of chewing insects. Here, we characterize the volatile cues emitted by turnip plants (Brassica rapa) under attack by an aphid (Myzus persicae) or by the chewing lepidopteran larva Heliothis virescens. We also tested the behavioral responses of M. persicae individuals to the odors of undamaged and herbivore-damaged plants presented singly or in combination, as well as to the odor of crushed conspecifics (simulating predation). Gas chromatographic analysis of the volatile blend of infested turnips revealed distinct profiles for both aphid- and caterpillar- induced plants, with induced compounds including green-leaf alcohols, esters, and isothiocyanates. In behavioral trials, aphids exhibited increased activity in the presence of plant odors and positive attraction to undamaged turnip plants. However, aphids exhibited a strong preference for the odors of healthy versus plants subjected to herbivore damage, and neither aphid- or caterpillar-damaged plants were attractive compared to clean-air controls. Reduced aphid attraction to herbivore-infested plants may bemediated by changes in the volatile blend constituent composition, including large amounts of isothiocyanates and green-leaf volatiles or, in the case of aphid-infested plants, of the aphid alarm pheromone, (E)-b-farnesene. [less ▲]

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See detailSelf-assemblage and quorum in the earthworm Eisenia fetida (Oligochaete, Lumbricidae)
Zirbes, Lara ULg; Brostaux, Yves ULg; Mescher, Mark et al

in PLoS ONE (2012), 7(3), 32564

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See detailEarthworms smell microorganisms in soil
Zirbes, Lara ULg; Verheggen, François ULg; Mescher, Mark et al

Poster (2011)

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See detailAlarm pheromones: Chemical signaling in response to danger
Verheggen, François ULg; Haubruge, Eric ULg; Mescher, Mark

in Litwack, Gerald (Ed.) Pheromones (2010)

Many animals respond to the threat of predation by producing alarm signals that warn other individuals of the presence of danger or otherwise reduce the success of predators. While alarm signals may be ... [more ▼]

Many animals respond to the threat of predation by producing alarm signals that warn other individuals of the presence of danger or otherwise reduce the success of predators. While alarm signals may be visual or auditory as well as chemical, alarm pheromones are common, especially among insects and aquatic organisms. Plants too emit chemical signals in response to attack by insect herbivores that recruit the herbivores’ natural enemies and can induce preparations for defense in neighboring plants (or other parts of the same plant). In this chapter we discuss our current understanding of chemical alarm signaling in a variety of animal groups (including social and pre-social insects, marine invertebrates, fish, and mammals) and in plants. We also briefly discuss the exploitation of alarm pheromones as foraging cues for natural enemies. We conclude with a brief discussion of the potential exploitation of alarm signaling to achieve the applied goal of managing pest species. [less ▲]

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See detailProduction of alarm pheromone by developing aphids varies in response to their social environment
Verheggen, François ULg; Haubruge, Eric ULg; Demoraes, Consuelo et al

Poster (2008)

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to ... [more ▼]

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to cease feeding, drop from their host plant, and disperse. Because aphid alarm pheromone confers apparent fitness benefits on recipients while its production and release likely entail costs for the emitting aphid, it could be adaptive for aphids to regulate their Eβf production in response to variation in the social environment. To explore this possibility we compared the production of Eβf by Acyrthosiphon pisum (Harris) individuals reared from first-instar larvae to the adult stage in isolation to that of individuals reared among conspecifics or among individuals of a different aphid species, Myzus persicae (Sulzer). Levels of EβF produced in each treatment were assayed by GC-FID quantification of EβF in volatiles collected from crushed aphids. Production of EβF by A. pisum reared in isolation (14.4ng/aphid) was significantly lower than that of aphids reared in a colony of conspecifics (49.1ng/aphid), reared in a M. persicae colony (31.5ng/aphid) or reared among conspecifics of another aaphid clone (52.7ng/aphid). Though A. pisum individuals in our experiments produced less EβF when reared among M. persicae than among conspecifics, this difference was not statistically significant. In a separate experiment we reared A. pisum individuals in isolation and exposed them to the odor of conspecifics. Under these conditions, EβF production was similar to that of aphids reared among conspecifics, suggesting that aphids use volatile cues to assess their social environment and regulate their production of alarm pheromone accordingly. [less ▲]

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See detailProduction of alarm pheromone by developing aphids varies in response to their social environment
Verheggen, François ULg; Mescher, Mark; Haubruge, Eric ULg et al

Conference (2008)

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to ... [more ▼]

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to cease feeding, drop from their host plant, and disperse. Because aphid alarm pheromone confers apparent fitness benefits on recipients while its production and release likely entail costs for the emitting aphid, it could be adaptive for aphids to regulate their Eβf production in response to variation in the social environment. To explore this possibility we compared the production of Eβf by Acyrthosiphon pisum (Harris) individuals reared from first-instar larvae to the adult stage in isolation to that of individuals reared among conspecifics or among individuals of a different aphid species, Myzus persicae (Sulzer). Levels of EβF produced in each treatment were assayed by GC-FID quantification of EβF in volatiles collected from crushed aphids. Production of EβF by A. pisum reared in isolation (14.4ng/aphid) was significantly lower than that of aphids reared in a colony of conspecifics (49.1ng/aphid), reared in a M. persicae colony (31.5ng/aphid) or reared among conspecifics of another aaphid clone (52.7ng/aphid). Though A. pisum individuals in our experiments produced less EβF when reared among M. persicae than among conspecifics, this difference was not statistically significant. In a separate experiment we reared A. pisum individuals in isolation and exposed them to the odor of conspecifics. Under these conditions, EβF production was similar to that of aphids reared among conspecifics, suggesting that aphids use volatile cues to assess their social environment and regulate their production of alarm pheromone accordingly. [less ▲]

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See detailAphids adapt their alarm pheromone production according to their social environment
Verheggen, François ULg; Haubruge, Eric ULg; Demoraes, Consuelo et al

Poster (2008)

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to ... [more ▼]

Aphid alarm pheromone—the volatile sesquiterpene (E)-β-farnesene (Eβf) in most species—is released in response to predation and other stresses and typically causes nearby aphids who receive the signal to cease feeding, drop from their host plant, and disperse. Because aphid alarm pheromone confers apparent fitness benefits on recipients while its production and release likely entail costs for the emitting aphid, it could be adaptive for aphids to regulate their Eβf production in response to variation in the social environment. To explore this possibility we compared the production of Eβf by Acyrthosiphon pisum (Harris) individuals reared from first-instar larvae to the adult stage in isolation to that of individuals reared among conspecifics or among individuals of a different aphid species, Myzus persicae (Sulzer). Levels of EβF produced in each treatment were assayed by GC-FID quantification of EβF in volatiles collected from crushed aphids. Production of EβF by A. pisum reared in isolation (14.4ng/aphid) was significantly lower than that of aphids reared in a colony of conspecifics (49.1ng/aphid), reared in a M. persicae colony (31.5ng/aphid) or reared among conspecifics of another aaphid clone (52.7ng/aphid). Though A. pisum individuals in our experiments produced less EβF when reared among M. persicae than among conspecifics, this difference was not statistically significant. In a separate experiment we reared A. pisum individuals in isolation and exposed them to the odor of conspecifics. Under these conditions, EβF production was similar to that of aphids reared among conspecifics, suggesting that aphids use volatile cues to assess their social environment and regulate their production of alarm pheromone accordingly. [less ▲]

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See detailEmission of alarm pheromone in aphids: A contagious phenomenon?
Verheggen, François ULg; Mescher, Mark; Francis, Frédéric ULg et al

Poster (2008)

Detailed reference viewed: 10 (1 ULg)