Open AccessArticle
Adaptation of an Invasive Pest to Novel Environments: Life History Traits of Drosophila suzukii in Coastal and Mainland Areas of Greece during Overwintering
by
, , , and *
Department of Agriculture, Crop Production and Rural Environment, University of Thessaly, Fytokou St., 38446 Volos, Greece
*
Author to whom correspondence should be addressed.
Academic Editors: Jeanne M. Fair, Martha Desmond and Maria Capovilla
Received: 20 May 2021
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Revised: 7 July 2021
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Accepted: 28 July 2021
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Published: 29 July 2021
Simple Summary
Drosophila suzukii, also known as the spotted wing Drosophila, is a notorious pest of several high-value fruits including strawberries and sweet cherries. Adult D. suzukii flies exhibit two morphs: summer morphs (SM) and winter morphs (WM). The two seasonal phenotypes help this pest to perform better in temperate climates. WM have a darker cuticle and larger wings compared to SM, while WM females experience reproductive dormancy. We estimated the lifespan, the reproductive status of females and the number of produced offspring for WM and SM exposed to mild and cold winter field conditions, prevailing in two different geographic areas (coastal and mainland). Overall, WM exhibited a longer lifespan than SM and this difference was more pronounced for adults kept in the cold mainland area. The majority of SM females produced offspring during overwintering in the mild coastal area, but only a few SM were reproductively active in the cold mainland area. Some WM females produced progeny during overwintering in the mild conditions of the coastal area, but all WM females were in reproductive arrest in the mainland area. Overwintering females in the coastal area had a shorter lifespan and produced more progeny than those kept in the mainland area. High survival rates of WM provide indications of the successful performance of this phenotype in the adverse conditions of the cold climates. Additionally, the continuous reproductive activity of SM females and the onset of progeny production by WM females during overwintering in the coastal area indicate that the insect remains reproductively active throughout the year in areas with mild climatic conditions. Our findings support the successful adaptation of D. suzukii in both areas tested and can be used for the development of area-specific population models, based on the prevailing climatic conditions.