Winter fruit contribution to the performance of the invasive fruit fly Drosophila suzukii under different thermal regimes.

Polyphagous insect species develop using multiple host plants. Often considered beneficial, polyphagy can also be costly as host nutritional quality may vary. Drosophila suzukii (Matsumura) is an invasive species that can develop on numerous fruit species over the annual cycle.

Response of life-history traits to artificial and natural selection for virulence and nonvirulence in a Drosophila parastitoid, Asobara tabida.

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.

The Wide Potential Trophic Niche of the Asiatic Fruit Fly Drosophila suzukii: The Key of Its Invasion Success in Temperate Europe?

The Asiatic fruit fly Drosophila suzukii has recently invaded Europe and North and South America, causing severe damage to fruit production systems. Although agronomic host plants of that fly are now well documented, little is known about the suitability of wild and ornamental hosts in its exotic area. In order to study the potential trophic niche of D.

Structural and functional characterization of pseudopodocyte, a shaggy immune cell produced by two Drosophila species of the obscura group.

We recently reported that most of the Drosophila species of the obscura group were unable to mount cellular capsules and no lamellocyte was ever found in the hemolymph of any of the tested species. Only three species were able to encapsulate, despite lacking lamellocytes. Their encapsulation ability was always associated with the presence of an unpreviously described kind of capsule-forming immunocytes designated as "atypical hemocytes".

Strategies of avoidance of host immune defenses in Asobara species.

Eggs and larvae of endophagous parasitoids face the host's immunity reaction once they penetrate the insect host's hemocele. In order to overcome the host's immune barrier, endoparasitoids have developed various strategies. Conformer parasitoids hide and/or get protected from the attack by the host's immunity cells without interfering with the host's immune system.

Immune resistance of Drosophila hosts against Asobara parasitoids: cellular aspects.

The immunity of Drosophila relies on a variety of defenses cooperating to fight parasites and pathogens. The encapsulation reaction is the main hemocytic response neutralizing large parasites like endophagous parasitoids. The diversity of the mechanisms of immunoevasion evolved by Asobara parasitoids, together with the wide spectrum of Drosophila host species they can parasitize, make them ideal models to study and unravel the physiological and cellular aspects of host immunity.

The fly Drosophila subobscura: a natural case of innate immunity deficiency.

The Drosophila subobscura larvae were found to be unable to form a capsule around a parasitic egg or an inert foreign body. The specificity and physiological causes of this incapacity were also explored: analysis of the circulating hemocytes showed that no lamellocyte was ever found in D. subobscura host larvae.

Conversely to its sibling Drosophila melanogaster, D. simulans overcomes the immunosuppressive effects of the parasitoid Asobara citri.

The endoparasitoid Asobara citri avoids Drosophila melanogaster immune defenses, thanks to immune suppressive effects. We investigated whether this parasitoid could also circumvent the immune reaction of D. simulans, a sibling species of D.

Evolution of hemocyte concentration in the melanogaster subgroup species.

We explore two possible hypotheses about the ecological factors driving the evolution of hemocyte load in insects. The first is parasite infection risk, its variability and the genetic diversity of parasites. The other supposes that all the other factors of environmental stress drive the evolution through a pleiotropic selection on metabolic rate.