| Title: | Cuticular Hydrocarbon Trails Released by Host Larvae Lose their Kairomonal Activity for Parasitoids by Solidification |
| Author(s): | Awater-Salendo S; Voigt D; Hilker M; Furstenau B; |
| Address: | "Federal Research Centre for Cultivated Plants, Institute for Ecological Chemistry, Plant Analysis and Stored Product Protection, Julius Kuhn Institute, Konigin-Luise-Str.19, 14195, Berlin, Germany. Dahlem Centre of Plant Science, Institute of Biology, Applied Zoology/Animal Ecology, Freie Universitat Berlin, Haderslebener Str.9, 12163, Berlin, Germany. Institute of Botany, Faculty of Biology, Technische Universitat Dresden, Zellescher Weg 20b, 01217, Dresden, Germany. Federal Research Centre for Cultivated Plants, Institute for Ecological Chemistry, Plant Analysis and Stored Product Protection, Julius Kuhn Institute, Konigin-Luise-Str.19, 14195, Berlin, Germany. benjamin.fuerstenau@julius-kuehn.de" |
| DOI: | 10.1007/s10886-021-01310-w |
| ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Print) 0098-0331 (Linking) |
| Abstract: | "Successful host search by parasitic wasps is often mediated by host-associated chemical cues. The ectoparasitoid Holepyris sylvanidis is known to follow chemical trails released by host larvae of the confused flour beetle, Tribolium confusum, for short-range host location. Although the hexane-extractable trails consist of stable, long-chain cuticular hydrocarbons (CHCs) with low volatility, the kairomonal activity of a trail is lost two days after release. Here, we studied whether this loss of kairomonal activity is due to changes in the chemical trail composition induced by microbial activity. We chemically analyzed trails consisting of hexane extracts of T. confusum larvae after different time intervals past deposition under sterile and non-sterile conditions. GC-MS analyses revealed that the qualitative and quantitative pattern of the long-chain CHCs of larval trails did not significantly change over time, neither under non-sterile nor sterile conditions. Hence, our results show that the loss of kairomonal activity of host trails is not due to microbially induced changes of the CHC pattern of a trail. Interestingly, the kairomonal activity of trails consisting of host larval CHC extracts was recoverable after two days by applying hexane to them. After hexane evaporation, the parasitoids followed the reactivated host trails as they followed freshly laid ones. Cryo-scanning electron microscopy showed that the trails gradually formed filament-shaped microstructures within two days. This self-assemblage of CHCs was reversible by hexane application. Our study suggests that the long-chain CHCs of a host trail slowly undergo solidification by a self-assembling process, which reduces the accessibility of CHCs to the parasitoid's receptors as such that the trail is no longer eliciting trail-following behavior" |
| Keywords: | Animals Gas Chromatography-Mass Spectrometry *Host-Parasite Interactions Hydrocarbons/chemistry Larva/chemistry/growth & development/metabolism Odorants/analysis Olfactory Perception Pheromones/*chemistry/metabolism Tribolium/chemistry/growth & developmen; |
| Notes: | "MedlineAwater-Salendo, Sarah Voigt, Dagmar Hilker, Monika Furstenau, Benjamin eng 2021/09/17 J Chem Ecol. 2021 Dec; 47(12):998-1013. doi: 10.1007/s10886-021-01310-w. Epub 2021 Sep 16" |
