Vandereycken, Axel ; Université de Liège - ULiège > Sciences agronomiques > Entomologie fonctionnelle et évolutive
Durieux, Delphine ; Université de Liège - ULiège > Sciences agronomiques > Entomologie fonctionnelle et évolutive
Joie, Emilie ; Université de Liège - ULiège > Sciences agronomiques > Entomologie fonctionnelle et évolutive
Haubruge, Eric ; Université de Liège - ULiège > Services administratifs généraux > Vice-Recteur de Gembloux Agro Bio Tech
Verheggen, François ; Université de Liège - ULiège > Sciences agronomiques > Entomologie fonctionnelle et évolutive
Langue du document :
Anglais
Titre :
Impact of the Asian ladybeetles’ invasions on agro-ecosystems (Belgium)
Date de publication/diffusion :
23 septembre 2010
Nom de la manifestation :
International Symposium: Ecology of Aphidophaga 11
Lieu de la manifestation :
Perugia, Italie
Date de la manifestation :
19 -24 September 2010
Manifestation à portée :
International
Références de l'abstract :
The mulitcolored ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), originating from South-East of Asia, was imported in Europe 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 the continent. Now, H. axyridis is causing damages to the ecosystems through e.g. competition and 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 (potato, corn, wheat, broad bean). In 2009, we evaluated the occurrence of this ladybeetle, as well as the interactions with other aphid natural enemies (hoverflies, coccinellids and lacewings) in several agro-ecosystem sites in northern Wallonia (Belgium). For the inventory, we have used 2 sampling methods, (1) one sticky trap on the middle of each field and (2) several quadras of 1m² disposed along transects.
After one year of field observations, we observed 20 aphidophagous species including 13 coccinellid species and 9 hoverfly species. The invasive ladybird dominates the group of coccinellids generally in all crops in north Wallonia. Most of the catched coccinellid individuals were H. axyridis (63% of the coccinellids), Propylea 14-punctata (17%), or Coccinella 7-punctata (10%).
At the larval stage, H. axyridis was the most abundant aphidophagous species in corn field, while E. balteatus larvae (Diptera: Syrphidae) were the most abundant in wheat and broad bean fields and Chrysoperla sp. larvae (Nevroptera: Chrysomelidae) dominate the aphidophagous guild in potatoes.
At the adult stage, lacewings and hoverflies were the most abundant in wheat, potatoes and corn. Ladybirds (H. axyridis and C. 7-punctata) dominated in broad bean.
H. axyridis mainly reproduce in corn, with a maximal abundance of larvae observed at the beginning of July.
