title: Drosophila suzukii (Diptera: Drosophilidae) and its Potential Impact to Wine Grapes During Harvest in Two Cool Climate Wine Grape Production Regions.
abstract: Drosophila suzukii (Matsumura) is a global pest attacking various berry crops. D. suzukii lays eggs in damaged and in intact wine grape berries of the most soft-skinned varieties. Here, we describe the relative host utilization of different wine grape cultivars grown in Northern Italy and Oregon. Assessments of host berry utilization were performed in both field and laboratory settings. Results were correlated to physiological changes occurring during grape berry development starting at véraison and concluding during harvest. We found that oviposition increased with an increase in sugar content and a decrease of acidity levels. Oviposition increased with a decrease of penetration force. Penetration force, as a measure of skin hardness, is a critical component of host selection among the D. suzukii-exposed cultivars. We demonstrated that incised berries are more favorable for D. suzukii oviposition and as a nutrient substrate. Increased presence on wine grapes, as indicated by egg laying and increased longevity, was observed for flies that were exposed to incised berries as opposed to fully intact berries. D. suzukii flies can be found feeding on damaged wine grapes during the harvest period, especially when the skins of berries are negatively impacted due to cracking, disease, hail injury, and bird damage. Such an increase of feeding and oviposition may increase the likelihood of spoilage bacteria vectoring due to D. suzukii.
authors.affiliation: Technology Transfer Centre and Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach 1, 38010 San Michele all'Adige (TN), Italy. claudio.ioriatti@fmach.it.
authors.forename: C
authors.initials: C
authors.lastname: Ioriatti
authors.affiliation: Department of Horticulture, Oregon State University, 4017 Ag and Life Sciences Bldg. Corvallis, OR 97331-7304.
authors.forename: V
authors.initials: V
authors.lastname: Walton
authors.affiliation: Department of Horticulture, Oregon State University, 4017 Ag and Life Sciences Bldg. Corvallis, OR 97331-7304.
authors.forename: D
authors.initials: D
authors.lastname: Dalton
authors.affiliation: Technology Transfer Centre and Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach 1, 38010 San Michele all'Adige (TN), Italy.
authors.forename: G
authors.initials: G
authors.lastname: Anfora
authors.affiliation: Technology Transfer Centre and Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach 1, 38010 San Michele all'Adige (TN), Italy.
authors.forename: A
authors.initials: A
authors.lastname: Grassi
authors.affiliation: Technology Transfer Centre and Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach 1, 38010 San Michele all'Adige (TN), Italy.
authors.forename: S
authors.initials: S
authors.lastname: Maistri
authors.affiliation: Technology Transfer Centre and Research and Innovation Centre, Fondazione Edmund Mach, Via Edmund Mach 1, 38010 San Michele all'Adige (TN), Italy.
authors.forename: V
authors.initials: V
authors.lastname: Mazzoni
mesh_terms: D000383:Agriculture; D000818:Animals; D004330:Drosophila / Q000254:growth & development / Q000502:physiology*; D005247:Feeding Behavior; D020387:Food Chain; D007558:Italy; D007814:Larva / Q000254:growth & development / Q000502:physiology; D009922:Oregon; D010058:Oviposition; D010063:Ovum / Q000254:growth & development / Q000502:physiology; D013696:Temperature; D027843:Vitis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism
keywords: cultivar; invasive species; sour rot; spotted wing drosophila; susceptibility