Herbivore-induced volatile emission in black poplar: regulation and role in attracting herbivore enemies.
After herbivory, plants release volatile organic compounds from damaged foliage as well as from nearby undamaged leaves that attract herbivore enemies. Little is known about what controls the volatile emission differences between damaged and undamaged tissues and how these affect the orientation of herbivore enemies. We investigated volatile emission from damaged and adjacent undamaged foliage of black poplar (Populus nigra) after herbivory by gypsy moth (Lymantria dispar) caterpillars and determined the compounds mediating the attraction of the gypsy moth parasitoid Glyptapanteles liparidis (Braconidae). Female parasitoids were more attracted to gypsy moth-damaged leaves than to adjacent non-damaged leaves. The most characteristic volatiles of damaged versus neighbouring undamaged leaves included terpenes, green leaf volatiles and nitrogen-containing compounds, such as aldoximes and nitriles. Electrophysiological recordings and olfactometer bioassays demonstrated the importance of nitrogenous volatiles. Under field conditions, parasitic Hymenoptera were more attracted to traps baited with these substances than most other compounds. The differences in volatile emission profiles between damaged and undamaged foliage appear to be regulated by jasmonate signalling and the local activation of volatile biosynthesis. We conclude that characteristic volatiles from damaged black poplar foliage are essential cues enabling parasitoids to find their hosts.
Department of Biochemistry, Max Planck Institute for Chemical Ecology, 00745, Jena, Germany.
Andrea
A
Clavijo McCormick
Sandra
S
Irmisch
Andreas
A
Reinecke
G Andreas
GA
Boeckler
Daniel
D
Veit
Michael
M
Reichelt
Bill S
BS
Hansson
Jonathan
J
Gershenzon
Tobias G
TG
Köllner
Sybille B
SB
Unsicker
D000818:Animals; D005260:Female; D017343:Genes, Plant; D005838:Genotype; D060434:Herbivory; D007814:Larva; D009036:Moths / Q000469:parasitology / Q000502:physiology*; D010675:Pheromones / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry / Q000502:physiology; D032107:Populus / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D013729:Terpenes / Q000737:chemistry; D055549:Volatile Organic Compounds / Q000737:chemistry*; D014863:Wasps / Q000502:physiology*
D010675:Pheromones; D013729:Terpenes; D055549:Volatile Organic Compounds; C010411:insect attractants
Braconidae; Glyptapanteles liparidis; Lymantria dispar; phytohormones; Populus nigra; Salicaceae; cytochrome P450; herbivore-induced volatiles; indirect defence; terpene synthase