A model describing the population dynamics of Sitobion avenae and Coccinella septempunctata

A model that described the summer population dynamics of the cereal aphid Sitobion avenae (Carter et al., 1982) was modified and extended to include the population dynamics of the aphidophagous predator Coccinella septempunctata. New equations were formulated to describe the dependence of aphid development and reproduction on temperature. The predation interaction between the aphid and coccinellid was formulated with a modified form of the temperature-mediated functional response equation proposed by Mack et al. (1981) and Mack and Smilowitz (1982). The output obtained from the model provided a reasonably good fit to field data. Recommendations for further research are made based on these results and on a sensitivity analysis reported elsewhere (Skirvin et al., 1996).