Natural parasitism in fruit fly (Diptera: Tephritidae) and interaction with wild hosts surrounding apple orchards adjacent to Atlantic Forest fragments in Paraná State, Brazil.

The South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), is an important pest in the subtropical region of Brazil. This insect has tritrophic relation between wild fruits and parasitoids and is associated with apple (Malus domestica Borkh.) orchards adjacent to the Atlantic Forest in Paraná. We thus investigated the degree of infestation of the fruit fly and natural parasitism in wild and cultivated fruits surrounding apple orchards. For this purpose, we collected fruits of Acca sellowiana (Berg.) Burret, Campomanesia xanthocarpa (Mart), Eugenia uniflora L., Eugenia pyriformis Cambessèdes, Psidium cattleianum Sabine, Psidium guajava (L.), Annona neosericea Rainer and Eriobotrya japonica (Thumb) in apple orchards adjacent to the Atlantic Forest located in Campo do Tenente, Lapa and Porto Amazonas counties. In total, we collected 18,289 fruits during four growing years. The occurrence of A. fraterculus depends on the susceptible period of apple fruits. A. sellowiana and P. cattleianum were considered primary fruit fly multipliers and P. guajava was secondary, all occurring after the apple harvest (IS period). The group of parasitoids with A. fraterculus was Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae), Opius bellus (Gahan, 1930), Doryctobracon areolatus (Szépligeti, 1911) and Doryctobracon brasiliensis (Szépligeti, 1911) (Hymenoptera: Braconidae) all of which are first records in the Atlantic Forest in Paraná. First record of O. bellus occurring in the State of Paraná, as well as, first record of the tritrophic association between host plant A. neosericea, parasitoids D. areolatus and O. bellus and fruit fly A. fraterculus. The host P. cattleianum stood out among the Myrtaceae species in regard to the high diversity of parasitoid species (81% of parasitoids). The total number of Figitidae species (76.5%) was higher than that of Braconidae species. The influence of climatic events in southern Brazil on wild fruit production should be further studied to understand the association of A. fraterculus with the tritrophic relationship.