Abstract

Predatory long-legged flies of the genus Medetera are important, but currently understudied, natural enemies of Scolytinae bark beetles such as Ips typographus. Medetera flies lay eggs on beetle-infested trees, where the developing larvae find their prey, but the chemical cues used by Medetera to locate infested trees are currently unknown. To identify odors attracting Medetera signaticornis, a species in Europe, headspace samples were collected at several time-points through different stages of I. typographus attacks on logs of Norway spruce (Picea abies). The headspace samples were analyzed using combined gas chromatography and mass spectrometry (GC-MS), and gas chromatography coupled with electroantennographic detection (GC-EAD) to determine compounds that stimulate M. signaticornis antennae. Antennae of M. signaticornis males and females were found to detect (-)-cis-verbenol, (+)-trans-verbenol and myrtenol, which are known to be produced by bark beetles. Antennal responses were also observed for verbenene, isoterpinolene, alpha-pinene oxide, camphor, pinocamphone, terpinene-4-ol, myrtenal, borneol, alpha-terpineol, geranyl acetone, and verbenone, which are primarily produced by microorganisms, and alpha-pinene, alpha-fenchene, beta-pinene, camphene, 3-carene, limonene, gamma-terpinene, and terpinolene, known spruce tree compounds. In field experiments testing two synthetic blends containing 18 antennal active and two additional compounds 2-methyl-3-buten-2-ol and ipsdienol we observed significant attraction of M. signaticornis within 24 h. These attractive blends can form the basis for development of Medetera monitoring lures for use in future forest and pest management.

Keywords

Biocontrol; Electrophysiology; Host location; Kairomone; Predator-prey interaction; Sustainable forestry

Published in

Journal of Chemical Ecology
2023, Volume: 49, number: 7-8, pages: 451–464
Publisher: SPRINGER

SLU Authors

• Sousa, Maria

  • Department of Plant Protection Biology, Swedish University of Agricultural Sciences
    

• Birgersson, Göran

  • Department of Plant Protection Biology, Swedish University of Agricultural Sciences
    

• Karlsson Green, Kristina

  • Department of Plant Protection Biology, Swedish University of Agricultural Sciences
    

• Becher, Paul

  • Department of Plant Protection Biology, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network
SLU Forest Damage Center


Sustainable Development Goals

Protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss


UKÄ Subject classification

Forest Science
Biochemistry and Molecular Biology
Ecology


Publication identifier

DOI: https://doi.org/10.1007/s10886-023-01405-6

Permanent link to this page (URI)

https://res.slu.se/id/publ/121377