
Selection by parasitoid females among closely related hosts based on volatiles: Identifying relevant chemical cues
Author(s) -
Fors Lisa,
Mozuraitis Raimondas,
BlažytėČereškienė Laima,
Verschut Thomas A.,
Hambäck Peter A.
Publication year - 2018
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.3877
Subject(s) - biology , parasitoid , host (biology) , selection (genetic algorithm) , olfactometer , zoology , herbivore , ecology , larva , olfactory cues , olfaction , artificial intelligence , computer science
Parasitoid fitness is influenced by the ability to overcome host defense strategies and by the ability of parasitoid females to select high‐quality host individuals. When females are unable to differentiate among hosts, their fitness will decrease with an increasing abundance of resistant hosts. To understand the effect of mixed host populations on female fitness, it is therefore necessary to investigate the ability of female parasitoids to select among hosts. Here, we used behavioral assays, headspace volatile collection, and electrophysiology to study the ability of Asecodes parviclava to use olfactory cues to select between a susceptible host ( Galerucella calmariensis ) and a resistant host ( Galerucella pusilla ) from a distance. Our studies show that parasitoid females have the capacity to distinguish the two hosts and that the selection behavior is acquired through experiences during earlier life stages. Further, we identified two volatiles (α‐terpinolene and [ E ]‐β‐ocimene) which amounts differ between the two plant–herbivore systems and that caused behavioral and electrophysiological responses. The consequence of this selection behavior is that females have the capacity to avoid laying eggs in G. pusilla , where the egg mortality is higher due to much stronger immune responses toward A. parviclava than in larvae of G . calmariensis .