Identification of Pheromone Components of Plagionotus detritus (Coleoptera: Cerambycidae), and Attraction of Conspecifics, Competitors, and Natural Enemies to the Pheromone Blend

Abstract

(1) Background: The principal aim of our work was to identify pheromone components for Plagionotus detritus (L.) (Coleoptera: Cerambycidae), which could be exploited for developing a pheromone-based monitoring system for the complementary purposes of plant protection in areas where it might become a pest, and natural conservation in areas where it is rare or endangered. (2) Methods: Collection and analysis of headspace volatiles were carried out with field-collected beetles. Bioactive volatile compounds identified [(R)-3-hydroxyhexan-2-one and (S)-2-hydroxyoctan-3-one] from extracts of males were purchased [(±)-3-hydroxyhexan-2-one], and synthesized [(S)-2-hydroxyoctan-3-one] and field-tested. Electroantennogram assays showed that antennae of the predatory beetle Clerus mutillarius F. (Coleoptera: Cleridae) also responded to the synthetic compounds. (3) Results: A two-component aggregation-sex pheromone consisting of (R)-3-hydroxyhexan-2-one and (S)-2-hydroxyoctan-3-one was identified for P. detritus. (±)-3-hydroxyhexan-2-one and (S)-2-hydroxyoctan-3-one attracted adults of P. detritus in field bioassays. Adults of the clerid C. mutillarius also were attracted to both compounds. The cerambycid Xylotrechus antilope Schönh was significantly attracted to traps baited with (S)-2-hydroxyoctan-3-one alone or the blend containing this compound. (4) Conclusions: Our data confirmed that 3-hydroxyhexan-2-one and 2-hydroxyoctan-3-one are male-produced pheromone components for P. detritus. These results show that both intraspecific and interspecific communication may play key roles in longhorn beetle life history and ecology, with closely and more distantly related species eavesdropping on each other’s signals.

Longhorn beetles and predatory clerid beetles attracted to a blend of longhorn beetle pheromone compounds in a Central European oak forest (Coleoptera: Cerambycidae, Cleridae)

“…Our follow‐up electroantennographic studies showed that antennae of both sexes of C. mutillarius were significantly stimulated by 3‐hydroxyhexan‐2‐one and 2‐methylbutan‐1‐ol, and antennae of males also responded to syn ‐2,3‐hexanediol. These findings are consistent with the previously noted attraction of this clerid species to the binary pheromone of the sympatric cerambycid P. detritus , 3‐hydroxyhexan‐2‐one and ( S )‐2‐hydroxyoctan‐3‐one (Imrei et al, 2021). These results suggest that the clerid may be eavesdropping on the pheromones of cerambycids as a mechanism for finding potential prey, in the form of cerambycid eggs, larvae or adults.…”

“…Further experiments would be required to test these variables and determine which are most important for trap captures. However, this funnel trap, fitted with a light green funnel, was used to catch the cerambycid Plagionotus floralis (Pallas) (Imrei et al, 2014; Toshova et al, 2010) and with a transparent funnel to catch the cerambycids Molorchus umbellatarum (Schreber) (Imrei et al, 2012) and Plagionotus arcuatus arcuatus (L.) (Imrei et al, 2019), and the congener P. detritus (L.) (Imrei et al, 2021).…”

Cerambycid pheromones affect catches ofPhymatodes aeneus(Coleoptera: Cerambycidae) andThanasimus undatulus(Coleoptera: Cleridae) in ethanol-baited multiple-funnel traps in the Pacific Northwest, United States of America

“…The cerambycid pheromone sulcatol (Meier et al 2019) attracted the woodborer Leptostylus asperatus (Haldemann) (Coleoptera: Cerambycidae) and four species of predators in Georgia (Miller and Crowe 2020). In Europe, traps baited with blends of 3,2-hydroxyketones were attractive to two cerambycid species and to the predator Clerus mutillarius Fabricius (Coleoptera: Cleridae) (Imrei et al 2021).…”