Insects betray themselves in nature to predators by rapid isomerization of green leaf volatiles.
Plants emit green leaf volatiles (GLVs) in response to herbivore damage, thereby attracting predators of the herbivores as part of an indirect defense. The GLV component of this indirect defense was thought to be a general wound signal lacking herbivore-specific information. We found that Manduca sexta-infested Nicotiana attenuata attract the generalist hemipteran predator Geocoris spp. as the result of an herbivore-induced decrease in the (Z)/(E) ratio of released GLVs, and that these changes in the volatile bouquet triple the foraging efficiency of predators in nature. These (E)-isomers are produced from plant-derived (Z)-isomers but are converted by a heat-labile constituent of herbivore oral secretions. Hence, attacking herbivores initiate the release of an indirect defense a full day before the attacked plants manufacture their own defensive compounds.
Allmann
Silke
S
Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, DE-07745 Jena, Germany.
Baldwin
Ian T
IT
D000447:Aldehydes / Q000378:metabolism*; D000818:Animals; D020062:Heteroptera / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D007536:Isomerism; D018402:Manduca / Q000378:metabolism / Q000502:physiology*; D009055:Mouth / Q000378:metabolism; D009812:Odorants; D010935:Plant Diseases; D018515:Plant Leaves / Q000378:metabolism*; D011235:Predatory Behavior; D013696:Temperature; D014026:Nicotiana / Q000378:metabolism*; D014835:Volatilization
D000447:Aldehydes; C010463:n-hexanal