POIRIE , Marylène

In several Hymenoptera, sexual fate is determined by the allelic composition at the complementary sex-determiner locus, a sex-determination mechanism that can strongly affect population dynamics. To date, the molecular identification of complementary sex determiner has only been achieved in the honeybee, where the complementary sex-determiner...

Drosophila melanogaster is a model organism for many fields in biology including immunology.Drosophila innate immunity is well described in case of bacterial and fungal infections but otherparasites, such as parasitoids, can be harmful and even lethal to Drosophila.We are working on the immune interaction between Drosophila larvae and the...

Leptopilina boulardi wasps are parasitoids that develop inside Drosophila melanogaster larvae by consuming their tissues, leading to the host death. They rely on venom injection at oviposition to circumvent the host immune response and ensure parasitism success. Venom of the ISm strain of L. boulardi mainly targets the main hemocyte type...

Most species in the order Hymenoptera are parasitoids that lay eggs and develop in or on the body of arthropod hosts. Several factors contribute to successful parasitism including venoms that wasps inject into hosts when ovipositing. Here, we review the composition, function and diversity of parasitoid venoms with emphasis on studies of wasps...

Some insects can develop immune resistance to koinobiont parasitoids. Reciprocally, adaptation to host immunology is critical for parasitoid success. Phylogenetic inertia and correlations between virulence against different hosts can act as constraints preventing these adaptations. Insights on these constraints may be obtained from the analysis...

International audience

This chapter reviews data available on parasitoid wasps' VLPs, mainly on the basis of their structure and composition. This leads to the discussion how to discriminate between virus-resembling VLPs and viruses, and to suggest that some of the VLPs might be cellular secreted vesicles, such as microvesicles and exosomes described in many...

International audience

Several parasitoids of the genus Psyttalia have been repeatedly introduced as biological control agents against the principal pest of olive, the fly Bactrocera oleae. However, few of the parasitoids released have become established and proved effective against B. oleae. It may however still be possible to find effective biological control...

Biopesticides based on Bacillus thuringiensis kurstaki (Btk) and israelensis (Bti) spores and toxins are widely used to control insect pests, increasing environmental risks to non-target biodiversity. Here, we tested for potential effects of larval ingestion of Bt commercial formulations on Drosophila species. Doses equivalent to those...

Commercial Bacillus thuringiensis formulations have non-intentional adverse effects on Drosophila species. German Drosophila Meeting

Legumes can meet their nitrogen requirements through root nodule symbiosis, which could also trigger plant systemic resistance against pests. The pea aphid , a legume pest, can harbour different facultative symbionts (FS) influencing various traits of their hosts. It is therefore worth determining if and how the symbionts of the plant and the...

Environmental and health issues resulting from the intensive use of broad-spectrum chemical insecticides, have favored the spread of biological insecticides in the last decades. The most common, Bacillus thuringiensis (Bt), is a spore-forming bacterium which produces a varied range of insecticidal toxins. However, the field accumulation of...

Endoparasitoid wasps are essential regulators of insect pests in ecosystems as well as important biological control auxiliaries. Traits important for parasitism success, such as the injection of venom proteins at oviposition, have thus been mainly studied. However, identification of the key genes involved among the large number of genes...

National audience

National audience

The spotted wing Drosophila, Drosophila suzukii (Ds), became a major economic pest for fruit production since its establishment in Europe and America. Among potential control methods, only classical biological control appears to be a mean of sustainably regulating Ds in both cultivated and natural habitats. In the frame of risk assessment,...

The recent and rapid invasion of Europe and North-America by Drosophila suzukii has generated numerous laboratory and field studies since this fly species is an agricultural pest that causes economical losses by laying eggs and developing in ripening fruits, but also because of its relatedness with the model species Drosophila melanogaster...

We report here the first observation of Zaprionus indianus Gupta in mainland France. Five specimens of both sexes were trapped in a liquid vinegar bait in Cap d'Antibes (French Riviera) and their taxonomic identification was then performed by morphologi-cal and molecular analysis. Z. indianus is recognized as a fig pest in the invaded American...

Bioinsecticides made of the bacterium Bacillus thuringiensis (Bt) are the bioinsecticide best sale worldwide. Due to the governmental policies and the public opinion, the use of such products has increased exponentially over the last decade. Among Bt bioinsecticides, those based on the strain Bt var. kurstaki (Btk) are widely used in farming to...

Aspartylglucosaminidase (AGA) is a low-abundance intracellular enzyme that plays a keyrole in the last stage of glycoproteins degradation, and whose deficiency leads to humanaspartylglucosaminuria, a lysosomal storage disease. Surprisingly, high amounts of AGAlikeproteins are secreted in the venom of two phylogenetically distant hymenopteran...

Recent studies suggest that the pea aphid (Acyrthosiphon pisum) has low immune defenses. However, its immune components are largely undescribed, and notably, extensive characterization of circulating cells has been missing. Here, we report characterization of five cell categories in hemolymph of adults of the LL01 pea aphid clone, devoid of...

Differentiation of traits among populations can evolve by drift when gene flow is low relative to drift or selection when there are different local optima in each population (heterogeneous selection), whereas homogeneous selection tends to prevent evolution of such a differentiation. Analyses of geographical variations in venom composition have...

National audience

National audience