Insect growth regulators in baits: methoprene acceptability to foragers and effect on larval eastern yellowjackets (Hymenoptera: Vespidae) [Vespula maculifrons, Vespula germanica]

Methoprene was tested for its potential in controlling pestiferous New Jersey yellowjackets. Cat foot bait, with 0.5% methoprene, was found to have no repellent properties, whereas 5% methoprene was strongly repellent to foraging eastern yellowjackets, Vespula maculifrons (Buysson), in the field. Diluted honey bait with 0.05% methoprene attracted fewer foragers than control bait when tested simultaneously. However, a formulation of 0.08% methoprene in diluted honey was readily accepted when no competing baits were present. A technique for hand rearing final-stage yellowjacket larvae was developed and used to test the growth inhibiting effects of methoprene. Larvae fed 3 mu g of methoprene had significantly lower pupation rates than did controls.