Potential distribution and phenological development of the Mediterranean Corn Borer (Sesamia nonagrioides) under warming climate in Europe

Climate change has the potential to modify the current distribution and phenological development of insect pests. Using a generic phenological model coupled to a model to simulate potential mortality during the overwintering season, we analysed the potential distribution and phenological development of the Mediterranean Corn Borer (MCB) Sesamia nonagrioides, under simulated warming climate at three time horizons (Baseline, 2030s, 2050s) in Europe. The mortality model included the simulation of larvae survival in the roots under the soil surface, thus simulating temperature of the soil of a maize field. Results of survival estimate showed that mortality does not decrease noticeably spreading MCB in currently cold areas where it has never been reported, due to the potential survival already assured by the fraction of diapausing larvae in the roots. These results indicate that low temperatures affecting overwinter survival might not be the most important limiting factor determining MCB distribution. The development model linked to the estimate of survival including larvae diapausing in the soil showed a potential increase of generations in the Balkans and Turkey, and, to a more limited extent, in Germany. On the contrary, the estimated increase is negligible in the Mediterranean basin, due to the potential stressful effects of high temperatures. The models were implemented in a software component (MIMYCS.Borers) composed of discrete model units. This is one of the models of the framework MIMYCS for the simulation of mycotoxin contamination in grain maize. The component based software implementation can be easily re-used in any framework based on the Microsoft .NET platform, and it was used in the BioMA platform of the European Commission.