Showing results 21 to 26 of 26
  Occurrence de la coccinelle asiatique, Harmonia axyridis Pallas, dans les agro-écosystèmes wallonsVandereycken, Axel  ; Durieux, Delphine ; Joie, Emilie et alConference (2010, July 06) Detailed reference viewed: 10 (4 ULg)L'invasion des coccinelles asiatiques a-t-elle une influence sur les agro-écosystèmes?Vandereycken, Axel ; Verheggen, François ; Durieux, Delphine et alin Probio-Revue (2010), 33(Numéro 1), 6-10 Detailed reference viewed: 45 (12 ULg)The chemical ecology of ladybird beetlesDurieux, Delphine ; Verheggen, François ; Vandereycken, Axel et alConference (2010, May 05) Ladybird beetles (Coleoptera: Coccinellidae) use a wide variety of semiochemicals to communicate with each other, e.g. finding a mate, protecting themselves from predation or cannibalism, finding a ... [more ▼] Ladybird beetles (Coleoptera: Coccinellidae) use a wide variety of semiochemicals to communicate with each other, e.g. finding a mate, protecting themselves from predation or cannibalism, finding a shelter to overwinter or ensuring a better survival for their offspring. But chemical communication upon ladybeetles has also found recently to occur with their prey, their prey-host plants and even within their interactions with their natural enemies. Thorough studies on ladybird behaviours towards these compounds could lead to their practical implementation in integrated strategies using ladybirds to control pests, like aphids or mealybugs. [less ▲] Detailed reference viewed: 38 (8 ULg)Occurrence of the multicolored ladybird, Harmonia axyridis PALLAS in Walloon agro-ecosystemsVandereycken, Axel ; Durieux, Delphine ; Joie, Emilie et alConference (2010, May 05) The Asian ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), was imported in 1997 in Belgium to control aphid populations in greenhouses. It took only few years to the insect to get adapted ... [more ▼] The Asian ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), was imported in 1997 in Belgium to control aphid populations in greenhouses. It took only few years to the insect to get adapted to temperate climate conditions and to spread out all over Europe. Now, H. axyridis is one of the coccinellid with the biggest size in Belgium, causing damages to the ecosystems through e.g. intraguild predation (IGP). We are still lacking information about the consequences of the introduction of this superpredator in our agro-ecosystems. This work focuses on the potential impacts of H. axyridis on the entomofauna associated with several crops (potatos, corn, wheat, broad bean). We evaluated in 2009 the occurrence as well as the interactions between aphids and their natural enemies (hoverflies, coccinellids and lacewings) in several agro-ecosystem sites in northern Wallonia. After one year of field observations, were found thirteen coccinellid species, most of the catched individuals being H. axyridis with 64% of the coccinellids, Propylea 14-punctata, 15%, or Coccinella 7-punctata, 14%. This invasive ladybird dominates the group of coccinellids generally in all crops in north Wallonia. The results with the sticky traps show that the maximum occurrence of H. axyridis in crops is observed in chicory, sugar beet and potatoes. The relationship aphid-ladybird in wheat for example, brings out that increase of density of Asian ladybird in mid-July follow the increase of aphids (Sitobion avenae, Sitobion fragariae, Metopolophium dirhodum, Aphis fabae) in the end of June. We also observe that, in most agro-ecosystems, hoverflies and lacewings are the dominant aphid natural enemies. In all crops investigate, the multicolored ladybird occurs with 5% of the aphidophagous after the Chrysopidae, 12% and the Syrphidae, 76%. In 2009, the agro-ecosystems with the most aphidophagous species are carrot and broad bean and these habitats are dominated by hoverflies. [less ▲] Detailed reference viewed: 33 (4 ULg)Synthèse bibliographique : l’écologie chimique des coccinellesDurieux, Delphine ; Verheggen, François ; Vandereycken, Axel et alin Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2010), 14(2), 351-367 This paper reviews the chemical ecology of ladybird beetles (Coleoptera: Coccinellidae) to present the role of semiochemicals involved in plant-ladybird, prey-ladybird and predator-ladybird interactions ... [more ▼] This paper reviews the chemical ecology of ladybird beetles (Coleoptera: Coccinellidae) to present the role of semiochemicals involved in plant-ladybird, prey-ladybird and predator-ladybird interactions. Ladybird beetles use these compounds to locate their prey, mate, protect themselves from predation or cannibalism, find a shelter to overwinter or ensure a better survival for their offspring. Thorough studies on ladybird behaviours towards these compounds could lead to their practical implementation in integrated strategies using ladybirds to control pests, like aphids or mealybugs. [less ▲] Detailed reference viewed: 278 (62 ULg)Distribution Of Potential Bluetongue Vectors On Belgium FarmsZimmer, Jean-Yves ; Haubruge, Eric ; Francis, Frédéric et alin Veterinary Record : Journal of the British Veterinary Association (2008), 162(21), 700 Detailed reference viewed: 104 (78 ULg)
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