(Z)-oxacyclotridec-10-en-2-one, an alfalfa weevil feeding deterrent from Medicago rugosa

Abstract ( Z )-Oxacyclotridec-10-en-2-one, a constituent ofa steam volatile fraction from Medicago rugosa leaves and stems, inhibits adult alfalfa weevil feeding on an inert substrate, and may be responsible for the strong resistance to weevil feeding exhibited by this annual Medicago species.