title: Response of life-history traits to artificial and natural selection for virulence and nonvirulence in a Drosophila parastitoid, Asobara tabida.
abstract: Co-evolution of host-parasitoid interactions is determined by the costs of host resistance, which received empirical evidence, and the costs of parasitoid virulence, which have been mostly hypothesized. Asobara tabida is a parasitoid, which mainly parasitizes Drosophila melanogaster and D. subobscura, the first species being able to resist to the parasitoid development while the second species is not. To parasitize resistant hosts, including D. melanogaster, A. tabida develops sticky eggs, which prevent encapsulation, but this virulence mechanism may be costly. Interindividual and interpopulation variation in the proportion of sticky eggs respectively allowed us to (i) artificially select and compare life-history traits of a virulent and a nonvirulent laboratory strain, and (ii) compare a virulent and a nonvirulent field strain, to investigate the hypothetical costs of virulence. We observed strong differences between the 2 laboratory strains. The nonvirulent strain invested fewer resources in reproduction and walked less than the virulent one but lived longer. Concerning the field strains, we observed that the nonvirulent strain had larger wings while the virulent one walked more and faster. All together, our results suggest that virulence may not always be costly, but rather that different life histories associated with different levels of virulence may coexist at both intra- and interpopulation levels.
authors.affiliation: FRE 3498 EDYSAN, CNRS-Université de Picardie Jules Verne, 33 rue St Leu, Amiens, Cedex, France.|UMR 6553 ECOBIO, CNRS-Université Rennes 1, Campus de Beaulieu, avenue du Général Leclerc, Rennes, Cedex, France.|UMR 7263 IMBE, AMU - CNRS - IRD - UAPV, Université d'Avignon et des Pays de Vaucluse, 301 rue Baruch de Spinoza, 84916, Avignon Cedex 09, France.
authors.forename: Joffrey
authors.initials: J
authors.lastname: Moiroux
authors.affiliation: UMR 6553 ECOBIO, CNRS-Université Rennes 1, Campus de Beaulieu, avenue du Général Leclerc, Rennes, Cedex, France.
authors.forename: Joan
authors.initials: J
authors.lastname: van Baaren
authors.affiliation: FRE 3498 EDYSAN, CNRS-Université de Picardie Jules Verne, 33 rue St Leu, Amiens, Cedex, France.
authors.forename: Mathilde
authors.initials: M
authors.lastname: Poyet
authors.affiliation: FRE 3498 EDYSAN, CNRS-Université de Picardie Jules Verne, 33 rue St Leu, Amiens, Cedex, France.
authors.forename: Aude
authors.initials: A
authors.lastname: Couty
authors.affiliation: FRE 3498 EDYSAN, CNRS-Université de Picardie Jules Verne, 33 rue St Leu, Amiens, Cedex, France.
authors.forename: Patrice
authors.initials: P
authors.lastname: Eslin
authors.affiliation: FRE 3498 EDYSAN, CNRS-Université de Picardie Jules Verne, 33 rue St Leu, Amiens, Cedex, France.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Prévost
authors.affiliation: FRE 3498 EDYSAN, CNRS-Université de Picardie Jules Verne, 33 rue St Leu, Amiens, Cedex, France.
authors.forename: Jérémy
authors.initials: J
authors.lastname: Séguin
authors.affiliation: FRE 3498 EDYSAN, CNRS-Université de Picardie Jules Verne, 33 rue St Leu, Amiens, Cedex, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Le Roux
mesh_terms: D000818:Animals; D002980:Climate; D004331:Drosophila melanogaster / Q000469:parasitology; D005260:Female; D006790:Host-Parasite Interactions / Q000235:genetics*; D000071421:Life History Traits; D008124:Locomotion; D008297:Male; D012098:Reproduction; D012641:Selection, Genetic; D000068618:Selective Breeding; D014774:Virulence; D014863:Wasps / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*
keywords: encapsulation; geographic variation; host resistance; trade-offs