Macroecological Patterns of Fruit Infestation Rates by the Invasive Fly Drosophila suzukii in the Reservoir Host Plant Sambucus nigra &dagger;

¹ EDYSAN, UMR 7058 CNRS, Université de Picardie Jules Verne, 1 rue des Louvels, 80037 Amiens Cedex 1, France
² CPIE des Pays de l'Oise, 6/8 rue des Jardiniers, 60300 Senlis, France
³ Université Clermont Auvergne, CNRS, GEOLAB, Maison des Sciences de l'Homme, 4 rue Ledru, 63000 Clermont-Ferrand, France
⁴ UMR Institut Sophia Agrobiotech, Equipe Recherche et Développement en Lutte Biologique, 400 route des Chappes, BP167, 06903 Sophia Antipolis, France
⁵ UMR ECOBIO CNRS 6553, Université de Rennes 1, 263 Avenue du Général Leclerc, CS 74205, 35042 Rennes Cedex, France
⁶ INRAE UMR 1065 SAVE, Campus de la Grande-Ferrade, 71 avenue Edouard Boulaux, CS 20032, 33 882 Villenave d'Ornon Cedex, France
⁷ CBGP, Univ Montpellier, CIRAD, INRAE, Institut Agro, IRD, Montpellier, France
⁸ CTIFL - Centre de Balandran, 751 Chemin de Balandran, 30127 Bellegarde, France
⁹ UMR CNRS 5558 Biométrie et Biologie Evolutive, Université Claude Bernard Lyon 1, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne Cedex, France
¹⁰ UMR 950 INRAE UCN EVA "Ecophysiologie Végétale Agronomie et Nutritions NCS", Université de Caen Normandie, Esplanade de la Paix, 14032 Caen Cedex, France
¹¹ Univ. Grenoble Alpes, INRAE, LESSEM, 2 rue de la Papeterie-BP 76, 38402 Saint-Martin-d'Hères, France
¹² Université de Lorraine, INRAE, LAE, 54000 Nancy, France
¹³ Institut de Recherche sur la Biologie de l'Insecte, IRBI UMR7261, CNRS, Université de Tours, Parc Grandmont, 37200 Tours, France

Published: 16 March 2021 by MDPI in The 1st International Electronic Conference on Biological Diversity, Ecology and Evolution session Invasive Species and Diversity

https://doi.org/10.3390/BDEE2021-09469

Abstract:

The invasive pest Drosophila suzukii (Matsumura, 1931) is a fruit fly native to Asia that infests a wide variety of cultivated and wild fruits, causing important damages on agricultural production. Wild plant species are major reservoirs for D. suzukii populations but their infestation rates varies greatly among geographical areas. This heterogeneity could partly be caused by a heterogeneity of environmental conditions acting across different spatial scales. This study aimed to disentangle the relative roles of macroclimatic, landscape and local factors that could affect the success of D. suzukii infestation of elderberry fruits (Sambucus nigra), a major and widespread host plant along climatic gradients. We collected elderberry fruits and measured vegetative and reproductive life traits of the plants in 215 sites distributed in 13 regions from North to South France during summer 2020. We counted the number of D. suzukii emerging from sampled fruits and tested for an effect of macroclimatic, landscape and local abiotic and biotic variables, as well as plant traits using linear mixed models with region as random factor. Latitude and mean maximum temperature had respectively the strongest positive and negative effects on mean infestation rates across regions (R = 0.761, p = 0.003 and R = −0.758, p = 0.004). Mixed models also showed that fruit infestation rate increased with the number of mature fruits within corymb and with forest cover in a 100 m radius around sampling sites and decreased with mean maximum temperature. The latitudinal and climatic clines in infestation rates suggests that D. suzukii population size might vary greatly among geographic regions. Our results also suggest that population sizes are larger in the presence of semi-natural habitats such as forest patches in the surrounding landscape. Our work contributes to enhancing our understanding of D. suzukii ecology, which is important to predict how infestation rates might change in the context of global climatic changes.