Title: | Southern Pine Beetle (Coleoptera: Curculionidae: Scolytinae) Pheromone Component trans-Verbenol: Enantiomeric Specificity and Potential as a Lure Adjuvant |
Author(s): | Shepherd WP; Sullivan BT; |
Address: | "USDA Forest Service, Southern Research Station, Pineville, LA" |
ISSN/ISBN: | 1938-2936 (Electronic) 0046-225X (Linking) |
Abstract: | "The southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) utilizes a multi-component aggregation pheromone to mediate mass-attacks and thereby colonize otherwise unsusceptible trees. Females produce the attractant frontalin and a synergist, trans-verbenol. We investigated trans-verbenol to determine whether enantiomeric composition, airborne concentration, and possibly other factors might affect its biological activity. Newly-emerged females from Mississippi populations produced 54-87% of the (-)-enantiomer; females initiating galleries in logs produced lower amounts and a wider range of enantiomeric ratios [12-92% (-)]. Coupled gas chromatography-electroantennographic detection (GC-EAD) studies did not suggest large differences in the concentration threshold of olfaction for the two enantiomers. We examined the effect of adding trans-verbenol to traps located outside infested areas and baited with components of the aggregation attractant. Male attraction was similarly increased by lures with 3, 81, or 98% of the (-)-enantiomer of trans-verbenol, whereas females preferred 81 over 3%. When release rate of 81% (-)-trans-verbenol in traps was varied across three orders of magnitude (0.3, 3, and 30 mg/d), the data suggested a positive dose-response trend. A high release (i.e., 2-5 g/d) device of host-odor alpha-pinene had a much stronger enhancing effect on trap catches than a trans-verbenol device (~30 mg/d), and trans-verbenol did not further enhance attraction when alpha-pinene was present. Our results suggest that the weak attraction-enhancing activity of trans-verbenol reported previously cannot be improved by adjusting the enantiomeric composition or release rate of lures, and furthermore there are no anticipated benefits of adding trans-verbenol to the D. frontalis monitoring lure" |
Keywords: | Animals Bicyclic Monoterpenes Female Insect Control Male Monoterpenes/chemistry/*metabolism Smell Stereoisomerism Weevils/*metabolism; |
Notes: | "MedlineShepherd, William P Sullivan, Brian T eng England 2018/11/27 Environ Entomol. 2019 Feb 13; 48(1):193-201. doi: 10.1093/ee/nvy169" |