Abundance and phenological model of Harmonia
axyridis Pallas (Coleoptera: Coccinellidae) in field crops
Vandereycken Axel 1; Brostaux Yves2; Joie Emilie 1; Caparros Rudy1, Haubruge Eric 1; Verheggen François J. 1 a.vandereycken@ulg.ac.be
1Unité d’Entomologie fonc2onnelle et évolu2ve – Université de Liège – Gembloux Agro-‐Bio Tech – Gembloux, Belgique
2 Unité de Sta2s2que, Informa2que et Mathéma2que appliquées – Université de Liège – Gembloux Agro-‐Bio Tech – Gembloux, Belgique
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IntroducOon
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Material and Methods
§ Sampling from 2009 to 2011
§ Observa2on period: March to September
§ Crops: wheat, broad bean, corn and potato
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Results
The MulOcolored Asian ladybeetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), was introduced into Western Europe in the late 1990s. This exo2c and invasive species is known to thrive principally in shrubs and arboreal habitats. It is known to control aphids’ popula2ons and it is also a voracious predator of na2ve aphidophages. We focus our work on H. axyridis annual
abundance in various field crops and on its phenological model. An aphidophagous sampling
was performed from 2009 to 2011 in four agrosystems: broad bean, wheat, corn and potato.
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Conclusion
Financially supported by “Service Public de Wallonie” and by “Fonds pour la forma3on à la Recherche dans l’Industrie et l’Agriculture (FRIA)”
§ Sampling method: visual observa2ons with quadrats of
1m² on transect (48 quadrats per crop and per week)
§ Determina2on and coun2ng of aphidophagous species
(eggs, larvae, adults) and aphid species
0 20 40 60 80
Corn Wheat Potato Broad bean
Me an n um be r o f H. ax yridis obse rv ed pe r 100 m ²
Larvae/pupae 2009 Larvae/pupae 2010 Larvae/pupae 2011
b b a n.s. n.s. n.s. 0 5 10 15 20 25
Corn Wheat Potato Broad bean
Me an n um be r o f H. ax yridis obse rv ed pe r 100 m ²
Adults 2009 Adults 2010 Adults 2011
n.s. n.s. b b a c a b
Fig1: Rela2onship between temperature (°C) and cumulated popula2on of larval and adult stages of H. axyridis and aphids in broad bean and corn.
Fig3: Mean number (±SE) of H.axyridis larvae observed in corn, wheat,
potato and broad bean from 2009 to 2011. Fig4: Mean number (±SE) of H.axyridis adults observed in corn, wheat, potato and broad bean from 2009 to 2011. Fig2: Phenological Logis2c model of H. axyridis (adults and larvae) in corn and broad bean.
Harmonia axyridis densi2es in these four field crops showed that (1) H. axyridis is able to complete its development cycle in corn and in broad
bean; (2) larvae and adults densi2es raised significantly (more than 3 2mes) from 2009 to 2011 in corn. The popula2on dynamics of aphids and
H. axyridis were characterized by a symmetric logis2c func2on (S-‐shape) based on the cumula2ve popula2on size. Temperature could be an
other factor which impact on H. axyridis abundance. The logis2c curves showed a sigmoid shape with an inflec2on point earlier in broad bean than in corn for aphids, larvae and adults of H. axyridis.
This study appears to strengthen the hypothesis that H. axyridis is also an invasive species of field crops.
Broad bean Corn Broad bean Corn 0 1000 2000 3000 4000 5000 6000 7000 0 5 10 15 20 25 0 500 1000 1500 2000 Cu mu la Ove d en si Oes o f a ph id s ( /m²) Cu mu la Ove d en si Oes o f a ph id op ha ges ( /m²) cumulaOve temperature (C°) 0 1000 2000 3000 4000 5000 6000 7000 0 5 10 15 20 25 0 500 1000 1500 2000 Cu m ula tiv e d en sit ies o f a ph ids (/ m ²) So m m e d es m oy en ne s h eb do m ad air es d es de ns ité s (/m ²) d'a ph idi ph ag es cumulative temperature (C°) Larve observé M Adulte observé M Larve théorique M Adulte théorique M Larve théorique F Adultet théorique F Larve observé F Adulte observé F Puceron observé M puceron théorique M Puceron théorique F Puceron observé F 0 1000 2000 3000 4000 5000 6000 7000 0 5 10 15 20 25 0 500 1000 1500 2000 Cu m ula tiv e d en sit ies o f a ph ids (/ m ²) So m m e d es m oy en ne s h eb do m ad air es d es de ns ité s (/m ²) d'a ph idi ph ag es cumulative temperature (C°) Larve observé M Adulte observé M Larve théorique M Adulte théorique M Larve théorique F Adultet théorique F Larve observé F Adulte observé F Puceron observé M puceron théorique M Puceron théorique F Puceron observé F Aphids Larvae Adults Corn Broad bean
