Evidence for a two-component external marking pheromone system in an aphid hyperparasitoid.
C Höller1, H J Williams, S B Vinson
1Institut für Phytopathologie, Universität Kiel, 2300, Kiel, Germany.
Journal of Chemical Ecology
|November 22, 2013
Summary
Dendrocerus carpenteri females avoid superparasitism using time-dependent chemical cues. They distinguish self-parasitized from conspecific-parasitized hosts via two markers, aiding reproductive success in aphid parasitoid control.
Area of Science:
- Entomology
- Chemical Ecology
- Behavioral Ecology
Background:
- Dendrocerus carpenteri is a solitary ectohyperparasitoid of aphid primary parasitoids.
- Superparasitism avoidance is crucial for solitary parasitoids to maximize offspring survival.
Purpose of the Study:
- To investigate the host discrimination mechanisms of Dendrocerus carpenteri.
- To understand the role of chemical markers in time-dependent host selection.
Main Methods:
- Observational studies on oviposition behavior.
- Analysis of chemical markers on mummy shells.
- Gas chromatography (GC) and freezing sensitivity tests for marker characterization.
Main Results:
- D. carpenteri females avoid superparasitism, with avoidance rates varying based on time since initial oviposition.
- Females discriminate between hosts parasitized by themselves and conspecifics.
- Two distinct chemical markers are used for discrimination: one short-lived and sensitive, the other persistent and stable.
- The ratio of these markers provides information on mark age and origin.
Conclusions:
- D. carpenteri employs a sophisticated time-dependent chemical communication system for host discrimination.
- The dual-marker system enhances the accuracy of recognizing host status and origin.
- This mechanism optimizes foraging efficiency and prevents superparasitism, crucial for this solitary hyperparasitoid.
