Trail pheromone of ponerine ant Gnamptogenys striatula: 4-methylgeranyl esters from Dufour's gland

• Published in: Journal of chemical ecology 2002-12, Vol.28 (12), p.2557-2567
• Main Authors: BLATRIX, Rumsais, SCHULZ, Claudia, JAISSON, Pierre, FRANCKE, Wittko, HEFETZ, Abraham
• Format: Article
• Language: English
• Subjects: Acyclic Monoterpenes; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Ants - chemistry; Autoecology; Behavior, Animal; Bioassays; Biological and medical sciences; Biological Assay; Chemical analysis; Esters; Fatty Acids - chemistry; Fatty Acids - pharmacology; Feeding Behavior; Food resources; Fundamental and applied biological sciences. Psychology; Isomerism; Locomotion; Pheromones; Pheromones - chemistry; Pheromones - pharmacology; Protozoa. Invertebrata; Resource exploitation; Terpenes - chemistry; Terpenes - pharmacology
• ISSN: 0098-0331; 1573-1561
• DOI: 10.1023/A:1021444321238

Dufour's gland is the origin of the trail pheromone of Gnamptogenys striatula. Chemical analysis of the glandular extracts revealed a series of new natural products, especially esters of (2E)-3,4,7-trimethyl-2,6-octadien-1-ol (4-methylgeraniol), and (2E)-3,4,7-trimethyl-2,6-nonadien-1-ol (a bishomogeraniol isomer) with medium-chain fatty acids. Bioassays with synthetic racemates of the esters revealed that the 4-methylgeranyl esters are highly active as trail pheromones, while the bishomogeranyl esters are either marginally active or not active at all. Assays with the individual 4-methylgeranyl esters showed each of them to be inferior to the glandular secretion in eliciting trail following. However, the mixture of racemic 4-methylgeranyl octanoate and the corresponding decanoate and dodecanoate, the main Dufour's volatile constituents, is as active as the natural secretion at similar concentration. We conclude that the trail pheromone constitutes a mixture of at least the 4-methylgeranyl esters identified in the gland. Since G. striatula generally preys on small arthropods rather than monopolizing large resources, we assume that trails are rarely used during foraging, but more often during nest migration. Production of new societies in this species is generally performed by budding, a period of considerable predation risk. Utilizing trails for efficient displacement in this context is, therefore, highly adaptive. This behavioral repertoire may also provide the ants with additional means of food resource exploitation.