Determination of parasitoids of Drosophila suzukii Matsumara (Diptera: Drosophilidae) and investigation of usage areas in orchards of the Eastern Mediterranean Region

Drosophila suzukii Matsumara 1931 (Diptera: Drosophilidae) is an invasive and quarantined fruit pest of Asian origin with a wide host preference. It was first detected in Erzurum in 2014 in our country. This study was carried out in laboratory and natural conditions between the years 2020-2022. Parasitoids of Drosophila suzukii in the highland and lowland areas of the Eastern Mediterranean Region were investigated and host-preference trials, development time at different temperatures, numerical-functional response and life schedule of Pachycrepoideus vindemmiae (Rondani, 1875) (Hymenoptera: Pteromalidae) and Leptopilina boulardi Förster (Hymenoptera: Figitidae) under laboratory conditions were studied. As a result of the study, the prevalence of D. suzukii in cherry, apricot, fig, apple, blackberry, mulberry, strawberry, citrus, plum, peach, nectarine and jujube fruits, as well as parasitoid species and their prevalence were determined. Four larval parasitoids of D.suzukii; Ganaspis bralisiensis (Ashmead, 1896), L. boulardi, Leptopilina heterotoma Förster (Hymenoptera: Figitidae) and Asobara japonica Belokobylskij (Hymenoptera: Braconidae) and 3 pupal parasitoids; P vindemmiae, Spalangia erythromera Forster (Hymenoptera: Pteromalidae) and Trichopria drosophilae (Perkins, 1910) (Hymenoptera: Diapriidae) were detected. Among these species, the most intensely detected species were P. vindemmiae and L. boulardi. For this reason, laboratory studies were carried out on these parasitoid species. It has been determined that A. japonica and G. bralisiensis species from larval parasitoids are new records for Turkey. In the laboratory studies of P. vindemmiae, it was determined that this parasitoid parasitizes the pupal stage of D. suzukii at 48 hours the most (68.7%).It was observed that it could not complete its pre-adult development at 15 °C and the adults developed best at 27 °C. It was detected that L. boulardi preferred and parasitized (45.3%) the 2nd instar larvae of D. suzukii. It was determined that it did not developed 15 and 18 °C in the pre-adult period, but it developed at 27 °C, but adults were best at 24 °C. According to the results obtained from the collected fruit samples, the time period in which the density of D. suzukii and its parasitoids is determined the most is between march-may and september-november in the plain area; In the highland part, it was determined as may-july and october-november. The fruits in which parasitoids are detected most are; peach, apple, strawberry, date, fig and cherry.