TY - JOUR
T1 - Common Cerambycid Pheromone Components as Attractants for Longhorn Beetles (Cerambycidae) Breeding in Ephemeral Oak Substrates in Northern Europe
AU - Molander, Mikael A.
AU - Winde, Inis B.
AU - Burman, Joseph
AU - Nyabuga, Franklin N.
AU - Lindblom, Tobias U.T.
AU - Hanks, Lawrence M.
AU - Millar, Jocelyn G.
AU - Larsson, Mattias C.
N1 - Funding Information:
The authors wish to thank Bj?rn Eriksson for help with statistics, and Marcus Vestlund and Jan Haikara for assistance during the field work. The Stina Werner Foundation at G? and the forest company Sveaskog (Jan Dahl and Per Petersson) kindly gave us permission to work on their properties, and we thank the Blekinge County Administrative Board for permission to work within G? nature reserve. G?ran Birgersson offered helpful support with the GC-MS and GC-EAD instrumentation at the SLU Alnarp Campus. Jonas Helgesson at Helgesson Tr?dtj?nst AB, Stefan Ekroth, Gunnar Isacsson, and forest companies Stora Enso and S?dra Skogs?garna, made significant contributions to the supply of oak wood substrates. Konrad Dettner helped us gain access to a non-electronic reference. The project was financed by research grants (to MCL) from the Swedish Forest Society Foundation (grant numbers: 1011-84/150-7 HJHIL, and 2016-029 LOMOL), Ekfr?mjandet: Erik Stenstr?m Foundation (grant: 2015-5), WWF Sweden (grant: Insight: SWE 0163; Local: 500 131) the Swedish Environmental Protection Agency (grant: NV-03135-14), The Research Council Formas (grant: 2016-01372), the Royal Swedish Academy of Sciences (to MAM, grant: BS2015-0065), and the United States Department of Agriculture, Animal and Plant Health Inspection Service (to JGM and LMH,?grant # 14-, 15-, 16-, 17, and 18-8130-1422-CA).
Publisher Copyright:
© 2019, The Author(s).
PY - 2019/7/15
Y1 - 2019/7/15
N2 - Longhorn beetles are ecologically important insects in forest ecosystems as decomposers of woody substrates, microhabitat engineers, and as components of forest food webs. These species can be greatly affected both positively and negatively by modern forestry management practices, and should be monitored accordingly. Through headspace sampling, coupled gas chromatography-electroantennography, gas chromatography-mass spectrometry, and field bioassays, we identified two compounds, 2-methyl-1-butanol and 3-hydroxy-2-hexanone, that constitute aggregation-sex pheromone attractants of three cerambycid species which breed primarily in different types of fresh, recently dead oak wood in Northern Europe: Pyrrhidium sanguineum (L.), Phymatodes alni ssp. alni (L.), and Phymatodes testaceus (L.) (Cerambycinae: Callidiini). Analyses of headspace volatiles collected from live insects indicated that the male-produced aggregation-sex pheromone of P. sanguineum is a 1–15:100 blend of (R)-2-methyl-1-butanol and (R)-3-hydroxy-2-hexanone, whereas the corresponding ratios for P. alni were 70–110:100. In field bioassays, adult P. sanguineum and P. alni were significantly attracted to multiple blends with varying ratios of the two compounds. When tested individually, the compounds were minimally attractive. In contrast, adult P. testaceus exhibited nonspecific attraction to both of the individual compounds and to different blends, despite the hydroxyketone not being part of its pheromone, which consists of (R)-2-methyl-1-butanol alone. Overall, our results suggest that a blend of 50:100 of racemic 2-methyl-1-butanol and 3-hydroxy-2-hexanone is appropriate for parallel, cost-efficient pheromone-based monitoring of all three species. In particular, these species could serve as useful indicators of how modern forestry practices affect a whole guild of saproxylic insects that require ephemeral deadwood substrates for successful breeding.
AB - Longhorn beetles are ecologically important insects in forest ecosystems as decomposers of woody substrates, microhabitat engineers, and as components of forest food webs. These species can be greatly affected both positively and negatively by modern forestry management practices, and should be monitored accordingly. Through headspace sampling, coupled gas chromatography-electroantennography, gas chromatography-mass spectrometry, and field bioassays, we identified two compounds, 2-methyl-1-butanol and 3-hydroxy-2-hexanone, that constitute aggregation-sex pheromone attractants of three cerambycid species which breed primarily in different types of fresh, recently dead oak wood in Northern Europe: Pyrrhidium sanguineum (L.), Phymatodes alni ssp. alni (L.), and Phymatodes testaceus (L.) (Cerambycinae: Callidiini). Analyses of headspace volatiles collected from live insects indicated that the male-produced aggregation-sex pheromone of P. sanguineum is a 1–15:100 blend of (R)-2-methyl-1-butanol and (R)-3-hydroxy-2-hexanone, whereas the corresponding ratios for P. alni were 70–110:100. In field bioassays, adult P. sanguineum and P. alni were significantly attracted to multiple blends with varying ratios of the two compounds. When tested individually, the compounds were minimally attractive. In contrast, adult P. testaceus exhibited nonspecific attraction to both of the individual compounds and to different blends, despite the hydroxyketone not being part of its pheromone, which consists of (R)-2-methyl-1-butanol alone. Overall, our results suggest that a blend of 50:100 of racemic 2-methyl-1-butanol and 3-hydroxy-2-hexanone is appropriate for parallel, cost-efficient pheromone-based monitoring of all three species. In particular, these species could serve as useful indicators of how modern forestry practices affect a whole guild of saproxylic insects that require ephemeral deadwood substrates for successful breeding.
KW - (R)-2-Methyl-1-butanol
KW - (R)-3-Hydroxy-2-hexanone
KW - Biodiversity
KW - Monitoring
KW - Red List
KW - Semiochemical
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U2 - 10.1007/s10886-019-01082-4
DO - 10.1007/s10886-019-01082-4
M3 - Article
C2 - 31254146
AN - SCOPUS:85068333783
VL - 45
SP - 537
EP - 548
JO - Journal of Chemical Ecology
JF - Journal of Chemical Ecology
SN - 0098-0331
IS - 7
ER -