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.

Multi-scale approach to biodiversity proxies of biological control service in European farmlands.

Intensive agriculture has profoundly altered biodiversity and trophic relationships in agricultural landscapes, leading to the deterioration of many ecosystem services such as pollination or biological control. Information on which spatio-temporal factors are simultaneously affecting crop pests and their natural enemies is required to improve conservation biological control practices. We conducted a study in 80 winter wheat crop fields distributed in three regions of North-western Europe (Brittany, Hauts-de-France and Wallonia), along intra-regional gradients of landscape complexity.

Effects of surfactins, Bacillus lipopeptides, on the behavior of an aphid and host selection by its parasitoid.

Background: Lipopeptides extracted from the Bacillus genus are emerging biopesticides, especially in protecting crops against phytopathogens. Among the three main families of lipopeptides, surfactins have been identified as having insecticidal properties against several insect orders. However, the sublethal effects of these promising biopesticides on insect pests and their natural enemies remain largely unknown.

Antagonist effects of the leek Allium porrum as a companion plant on aphid host plant colonization.

Combining a non-host plant (companion plant or CP) with a target cultivated plant is considered as a promising strategy to reduce pest pressure. Among the companion plants (CP) commonly used in integrated systems, those belonging to the Amaryllidaceae family (chives, garlic, onion, leek) exhibit characteristics related to certain volatile organic compounds (VOCs) with promising repellent potentialities. The aim of this work was to investigate the potential disruption of sweet pepper (host plant) colonization by the green peach aphid (Myzus persicae) when exposed to leek (Allium porrum) as a CP.

Plant infection by two different viruses induce contrasting changes of vectors fitness and behavior.

Insect-vectored plant viruses can induce changes in plant phenotypes, thus influencing plant-vector interactions in a way that may promote their dispersal according to their mode of transmission (i.e., circulative vs.

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.

Cascading effects of N input on tritrophic (plant-aphid-parasitoid) interactions.

Because N is frequently the most limiting mineral macronutrient for plants in terrestrial ecosystems, modulating N input may have ecological consequences through trophic levels. Thus, in agro-ecosystems, the success of natural enemies may depend not only from their herbivorous hosts but also from the host plant whose qualities may be modulated by N input. We manipulated foliar N concentrations by providing to plants three different nitrogen rates (control, optimal, and excessive).

Aphid Parasitoid Mothers Don't Always Know Best through the Whole Host Selection Process.

Parasitoid host selection behaviour has been extensively studied in experimentally simplified tritrophic systems formed by one single food chain (one plant, one herbivore and one parasitoid species). The "Mother knows best" hypothesis predicts that the preference for a plant-host complex should be positively correlated with plant quality for offspring performance. We studied the host selection behaviour of the generalist endoparasitoid Aphidius matricariae towards the black bean aphid Aphis fabae in the intercrop system including Vicia faba as a focal plant and its companion plant Camelina sativa.

Colonization of the biomass energy crop miscanthus by the three aphid species, Aphis fabae, Myzus persicae, and Rhopalosiphum padi.

Miscanthus is a perennial C4-grass that has received much interest as a potential of impact on the local agroecosytem. In this context, laboratory experiments were conducted to investigate the potential colonization of this new exotic plant species by three of the main aphid pest species of common crops in Picardie, northern France. In host preference experiments, the two polyphagous aphid species studied, Aphis fabae (Scop) and Myzus persicae (Sulzer), exhibited an xclusive preference for their host plant, whereas the cereal specialist Rhopalosiphum padi (L.

Trans-generational effects of mild heat stress on the life history traits of an aphid parasitoid.

Temperature changes are common in nature and insects are particularly exposed and sensitive to such variations which can be potential stresses, ultimately affecting life history traits and overall fitness. Braconids have been widely used to study the effects of temperature on host-parasitoid interactions and the present work focused on the solitary endoparasitoid Aphidius ervi Haliday (Hymenoptera: Braconidae Aphidiidae), an efficient biological control agent commercially used against aphids such as the potato aphid Macrosiphum euphorbiae Thomas (Sternorrhyncha: Aphididae). Contrary to previous studies using heat shocks at extreme temperatures, we evaluated the effects of mild heat stresses by transferring young parasitoid adults from the constant temperature of 20°C to either a warm (25°C) or hot (28°C) temperature, for either 1 h or 48 h.

Modulation of Aphid Vector Activity by Potato virus Y on In Vitro Potato Plants.

The effects of the infection of potato (Solanum tuberosum) plants by the nonpersistent Potato virus Y (PVY) were studied on the host plant colonization behavior of different colonizing (Myzus persicae) and noncolonizing (Aphis fabae, Brevicoryne brassicae, and Sitobion avenae) aphid species. The underlying questions of this study were to know how aphids respond when faced with PVY-infected plants and whether plant infection can modify the aphid behavior involved in PVY spread. Short-range orientation behavior was observed using a dual-choice set-up and aphid feeding behavior was monitored using the electrical penetration graph technique.

Dynamic use of fruit odours to locate host larvae: individual learning, physiological state and genetic variability as adaptive mechanisms.

This chapter presents a series of behavioral studies designed to document how Leptopilina spp. learn fruit odours in order to find and explore host-infested fruits. Experimental analyses of conditioned responses explored individual learning, physiological changes and genetic variability as adaptive mechanisms of the host searching behavior.

Potential effects of plant protease inhibitors, oryzacystatin I and soybean Bowman-Birk inhibitor, on the aphid parasitoid Aphidius ervi Haliday (Hymenoptera, Braconidae).

Protease inhibitors (PIs) have been shown to cause lethal and sublethal effects on aphids depending on the kind of PI and aphid species. Therefore, these proteins might affect aphid parasitoids directly by inhibiting their digestive proteolysis or indirectly via their development in a less suitable host. In our study, the risk of exposure and the potential effects of soybean Bowman-Birk inhibitor (SbBBI) and oryzacystatin I (OCI) on the aphid endoparasitoid Aphidius ervi were investigated using artificial diet to deliver PIs.

Effects of artificial diet containing GNA and GNA-expressing potatoes on the development of the aphid parasitoid Aphidius ervi Haliday (Hymenoptera: Aphidiidae).

Aphid parasitoids are important biological control agents. The possibility arises that whilst foraging on insect-resistant transgenic plants, they are themselves at risk from direct and indirect effects of the expression of a transgene used to control the pest species. A liquid artificial diet was successfully used to deliver the snowdrop lectin (Galanthus nivalis agglutinin; GNA) to the peach-potato aphid, Myzus persicae.

Direct and indirect sublethal effects of Galanthus nivalis agglutinin (GNA) on the development of a potato-aphid parasitoid, Aphelinus abdominalis (Hymenoptera: Aphelinidae).

Snowdrop lectin (Galanthus nivalis agglutinin, GNA), has been shown to confer partial resistance to two potato aphids Myzus persicae and Aulacorthum solani, when incorporated in artificial diet and/or expressed in transgenic potato. First-tier laboratory-scale experiments were conducted to assess the potential effect of GNA on the aphid parasitoid Aphelinus abdominalis. GNA (0.