LARVAL AND PUPAL PARASITISM OF THE STRAWBERRY LEAFROLLER (LEPIDOPTERA, TORTRICIDAE)

Fourteen parasitoid species were recovered from strawberry leafroller, Ancylis comptana (Froelich), larvae and pupae collected in central Io wa strawberry fields in 1987 and 1989. Parasitism by the two most abun dant parasitoid species, Itoplectis conquisitor (Say) (Hymenoptera: Ic hneumonidae) and Pediobius facialis (Giraud) (Hymenoptera: Eulophidae) , was synchronous with high A. comptana pupal densities. This is the f irst study in North America in which I. conquisitor and P. facialis we re the predominant parasitoids attacking immature A. comptana. In 1987 , cumulative percentage parasitism of the first A. comptana generation increased to 7% on 24 June. In 1989, the cumulative percentage parasi tism of the first larval generation increased to 5.5% on 23 June. Beca use strawberries have a relatively high tolerance for A. comptana leaf rolling and feeding activity, naturally occurring parasitoids should be conserved.