Identification of ant repellent allomone produced by social waspPolistes fuscatus (Hymenoptera: Vespidae).

Two active components were isolated from the ant repellent secretion produced by glandular cells on the sixth (terminal) gastral sternite ofPolistes fuscatus (F.) females. One of the components was identified as methyl palmitate. Field bioassays with synthetic methyl palmitate showed it had repellent activity againstSolenopsis geminata (F.)Forelius pruinosus (Roger), andPheidole sp. The effectiveness of the repellent was greater againstF. pruinosus andPheidole sp. than againstS. geminata. Four methyl ester homologs of methyl palmitate also were field tested for repellent activity: methyl myristate had repellent activity against all three ant species, whereas methyl stearate, methyl linoleate, and methyl linolenate exhibited no repellency.