Behavioral and Electrophysiological Responses of Tetropium fuscum (Coleoptera: Cerambycidae) to Pheromone and Spruce Volatiles

Abstract

The brown spruce longhorn beetle, Tetropium fuscum (F.), is an invasive wood-boring species in eastern Canada. Gas chromatographic/electroantennographic (GC/EAD) analyses of Norway and red spruce volatiles detected a number of consistent EAD-active responses to compounds that are known to be stress-induced in spruce. The effects of these EAD-active compounds on various aspects of adult behavior were tested. In two-choice olfactometer assays, a monoterpene spruce blend, (R)-(-)-linalool, (3Z,6E)-α-farnesene, (E)-β-farnesene and spruce essential oil were attractive to both sexes. However, when they were combined with the male-produced pheromone (fuscumol), they elicited a sex-specific response: females were significantly attracted to combinations of fuscumol plus either (3Z,6E)-α-farnesene, (E)-β-farnesene and spruce essential oil but males were not. Fuscumol alone was unattractive to either sex in the olfactometer. Males exposed to fuscumol, (3Z,6E)-α-farnesene, or a combination of both, but not (E)-β-farnesene, were more likely to engage in the pheromone calling posture relative to controls. Both the monoterpene spruce blend and spruce essential oil elicited significantly greater trap capture of both sexes of T. fuscum in the presence of fuscumol and ethanol than (3Z,6E)-α-farnesene or (R)-(-)-linalool, which did not elicit trap capture alone or in combination with fuscumol. The data support the hypothesis that stress-induced sesquiterpene components, such as (3Z,6E)-α-farnesene, are important for mediating close-range attraction and behavior in T. fuscum while the monoterpene components are important for long-range processes (trap capture).

2.4. Cerambycidae Latreille, 1802

“…A variety of chemical cues is used for host location, such as host kairomones, pheromones of other herbivores (e.g., bark beetles) or smoke volatiles. They usually contain shortchain alpha hydroxyketones or diols, fuscumol ( = geranyl ace tol) in Tetropium and some Lamiinae and possibly Cerambyc inae (Mitchell et al 2011), but occasion ally different compounds and/or more complex blends (e.g., Lacey et al 2008;Ray et al 2009 b); they may also work in synergy with host vola tiles (Ginzel & Hanks 2005;Silk et al 2007Silk et al , 2010. Volatile male produced sex (attracting females) or aggregation (attracting both sexes) pheromones are known in several Cerambyc inae, Lamiinae and Tetropium Kirby of Spondylid inae (Silk et al 2007 for the latter).…”

Preference of an exotic wood borer for stressed trees is more attributable to pre‐alighting than post‐alighting behaviour

“…However, previous studies have shown that high levels of moisture stress, such as those experienced by girdled trees in the present study, can alter the quantity and composition of volatiles emitted by trees (Kimmerer & Kozlowski, 1982;Millar et al, 1986;Ebel et al, 1995), which may influence host selection by Tetropium spp. Tetropium fuscum has also been reported to be attracted to monoterpenes and sesquiterpenes associated with stressed spruce trees (Sweeney et al, 2004;Silk et al, 2010). Tetropium fuscum has also been reported to be attracted to monoterpenes and sesquiterpenes associated with stressed spruce trees (Sweeney et al, 2004;Silk et al, 2010).…”

“…Becker, 1962;Broberg & Borden, 2005;Silk et al, 2010) and field trapping experiments (e.g. Becker, 1962;Broberg & Borden, 2005;Silk et al, 2010) and field trapping experiments (e.g.…”

“…Numerous studies have evaluated wood borer host selection mechanisms using laboratory bioassays (e.g. Becker, 1962;Broberg & Borden, 2005;Silk et al, 2010) and field trapping experiments (e.g. Ikeda et al, 1980;Montgomery & Wargo, 1983;Chénier & Philogène, 1989;Brattli et al, 1998;Sweeney et al, 2004).…”

Allelochemicals in Plant–Insect Interactions

“…However, 2,3-butanediol related to fermentation and microbial degradation are highly attractive to P. interrupta, which favors the odors of fermentation products. 72 Other plant volatiles also act synergistically with aggregation pheromones. 59 Allyl isothiocyanate, a specific odor component, is a breakdown product of glucosinolates in oilseed rape, B. napus.…”