Abstract
Olfaction plays a dominant role in insect communication. Alarm pheromones, which alert other insects of the same species of impending danger, are a major class of releaser pheromones. The major components of alarm pheromones in red imported fire ants, honeybees and aphids have been identified as 2-ethyl-3,6-dimethylpyrazine (2E-3,6-DP), isopentyl acetate (IPA), and E-β-farnesene (EβF), respectively. In this study, electroantennography (EAG) responses to EDP (a mixture of 2-ethyl-3,6-dimethylpyrazine and 2-ethyl-3,5-dimethylpyrazine), IPA and EβF were investigated in a wide range of insect species. Beside imported fire ants, the EDP (2-ethyl-3,6(5)-dimethylpyrazine) elicited significant EAG response from all other tested insects, including six ant species and one hybrid ant, honeybee, bagrada bug, lady beetle, housefly, small hive beetle, yellow fever mosquito, termite, bedbug, water hyacinth weevil, southern green stink bug and two aphid species. In contrast, IPA elicited significant EAG response only in the honeybee, red imported fire ant, an Aphaenogaster ant, and the water hyacinth weevil. The EβF only elicited EAG responses in two aphids, small hive beetle and housefly. The results clearly indicate that EDP can be detected by widespread insect species that did not coevolve with S. invicta and further suggested alkylpyrazine may activate multiple generally tuned olfactory receptors (ORs) across a wide number of insect species.
Highlights
The red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), is one of the worst invasive alien species in the world [1]
Since pure fire ant alarm pheromone was not available, we originally thought that Gas Chromatography-Electroantennographic Detection (GC-electroantennographic detection (EAD)) might be useful to measure the response of other insects to fire ant alarm pheromone in the isomer mixture
Since the GC-EAD response was too small to meet the need in this study, we elected to use the isomer mixture EDP with direct EAG measurement
Summary
The red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), is one of the worst invasive alien species in the world [1]. S. invicta was introduced from South America into the United States in Mobile, Alabama in the 1930s. Since it has spread extensively and become well established in 15 states in the U.S [2]. Fire ants are a significant public health hazard and an important pest in agriculture with an annual loss estimated to surpass $7 billion due to damage repair and control costs [3]. Like all other social insects, S. invicta, depend on sophisticated pheromonal communication for maintaining colony cohesiveness, sociality, and defense.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
