Response of insect relative growth rate to temperature and host-plant phenology: estimation and validation from field data.
Between 1975 to 2011, aphid Relative Growth Rates (RGR) were modelled as a function of mean outdoor temperature and host plant phenology. The model was applied to the grain aphid Sitobion avenae using data on aphid counts in winter wheat at two different climate regions in France (oceanic climate, Rennes (western France); continental climate, Paris). Mean observed aphid RGR was higher in Paris compared to the Rennes region. RGR increased with mean temperature, which is explained by aphid reproduction, growth and development being dependent on ambient temperature. From the stem extension to the heading stage in wheat, there was either a plateau in RGR values (Rennes) or an increase with a maximum at heading (Paris) due to high intrinsic rates of increase in aphids and also to aphid immigration. From the wheat flowering to the ripening stage, RGR decreased in both regions due to the low intrinsic rate of increase in aphids and high emigration rate linked to reduced nutrient quality in maturing wheat. The model validation process showed that the fitted models have more predictive power in the Paris region than in the Rennes region.
UMR 1349 IGEPP, Institut National de Recherche Agronomique, Le Rheu, France ; UMR CNRS 6553 ECOBIO, Université Rennes1, Rennes, France ; Service Génétique, Physiologie et Protection des Plantes, Arvalis-Institut-du-Végétal, Boigneville, France.
Mamadou
M
Ciss
UMR 1349 IGEPP, Institut National de Recherche Agronomique, Le Rheu, France.
Nicolas
N
Parisey
UMR CNRS 6553 ECOBIO, Université Rennes1, Rennes, France ; Service Génétique, Physiologie et Protection des Plantes, Arvalis-Institut-du-Végétal, Boigneville, France.
Gwenaëlle
G
Fournier
Service Génétique, Physiologie et Protection des Plantes, Arvalis-Institut-du-Végétal, Boigneville, France.
Pierre
P
Taupin
UMR 1349 IGEPP, Institut National de Recherche Agronomique, Le Rheu, France.
Charles-Antoine
CA
Dedryver
UMR CNRS 6553 ECOBIO, Université Rennes1, Rennes, France.
Jean-Sébastien
JS
Pierre
D000818:Animals; D001042:Aphids / Q000254:growth & development*; D004777:Environment; D035264:Flowers / Q000502:physiology; D005602:France; D008954:Models, Biological; D012098:Reproduction / Q000502:physiology; D013045:Species Specificity; D013696:Temperature; D014908:Triticum / Q000502:physiology*