| Title: | "Styrene, (+)-trans-(1R,4S,5S)-4-Thujanol and Oxygenated Monoterpenes Related to Host Stress Elicit Strong Electrophysiological Responses in the Bark Beetle Ips typographus" |
| Author(s): | Schiebe C; Unelius CR; Ganji S; Binyameen M; Birgersson G; Schlyter F; |
| Address: | "Chemical Ecology, Department Plant Protection Biology, Swedish University of Agricultural Sciences, PO Box 102, 230 53, Alnarp, Sweden. Department Chemistry and Biomedical Sciences, Linnaeus University, Stuvaregatan 2, 392 31, Kalmar, Sweden. Department Chemistry and Biomedical Sciences, Linnaeus University, Stuvaregatan 2, 392 31, Kalmar, Sweden. rikard.unelius@lnu.se. Department of Entomology, Faculty of Agricultural Sciences & Technology, Bahauddin Zakariya University, Multan, 60800, Pakistan. Faculty of Forestry & Wood Sci, Excellent Team for Mitigation, Czech University Life Sci Prague, Kamycka 129, Prague 6, 16521, Suchdol, Czech Republic" |
| DOI: | 10.1007/s10886-019-01070-8 |
| ISSN/ISBN: | 1573-1561 (Electronic) 0098-0331 (Print) 0098-0331 (Linking) |
| Abstract: | "Bark beetles kill apparently vigorous conifers during epidemics by means of pheromone-mediated aggregation. During non-endemic conditions the beetles are limited to use trees with poor defense, like wind-thrown. To find olfactory cues that help beetles to distinguish between trees with strong or weak defense, we collected volatiles from the bark surface of healthy felled or standing Picea abies trees. Furthermore, living trees were treated with methyl jasmonate in order to induce defense responses. Volatiles were analyzed by combined gas chromatography and electroantennographic detection (GC-EAD) on Ips typographus antennae. Compounds eliciting antennal responses were characterized by single sensillum recording for identification of specific olfactory sensory neurons (OSN). Release of monoterpene hydrocarbons decreased, while oxygenated compounds increased, from spring to early summer in felled trees. In both beetle sexes particular strong EAD activity was elicited by trace amounts of terpene alcohols and ketones. 4-Thujanol gave a very strong response and the absolute configuration of the tested natural product was assigned to be (+)-trans-(1R,4S,5S)-thujanol by stereoselective synthesis and enantioselective gas chromatography. One type of OSN responded to all ketones and five other OSN were characterized by the type of compounds that elicited responses. Three new OSN classes were found. Of the eight EAD-active compounds found in methyl jasmonate-treated bark, the known anti-attractant 1,8-cineole was the one most strongly induced. Our data support the hypothesis that highly active oxygenated host volatiles could serve as positive or negative cues for host selection in I. typographus and in other bark beetles" |
| Keywords: | Acetates/pharmacology Animals Bicyclic Monoterpenes Coleoptera/*physiology Cyclopentanes/pharmacology Electrophysiological Phenomena/drug effects Gas Chromatography-Mass Spectrometry Monoterpenes/chemical synthesis/*chemistry/pharmacology Oxylipins/pharma; |
| Notes: | "MedlineSchiebe, Christian Unelius, C Rikard Ganji, Suresh Binyameen, Muhammad Birgersson, Goran Schlyter, Fredrik eng 2019/05/06 J Chem Ecol. 2019 Jun; 45(5-6):474-489. doi: 10.1007/s10886-019-01070-8. Epub 2019 May 4" |
