A model to describe the reproductive rate in the aphid Sitobion avenae (Hemiptera: Aphididae): A case study

The development of a detailed population dynamics model to simulate changes in grain aphid (Sitobion avenae F.) populations on wheat in field conditions requires the identification of every component of the system. The present study proposes a deterministic model for the fecundity function. An optimality theory is applied here to model aphid reproduction in order to obtain a usable mathematical description of larvae laying rate. This rate is assumed to be mainly dependent on temperature since this effect is commonly observed in poikilothermic organisms. It is taken into account by using a thermodependent physiological time scale for measuring adult age. The resulting function is fitted with two data sets. Despite some bias, which is discussed, the model matches relatively well with the observations. The model framework may be easily extended to other species.