An ecological model to analyze and control the dynamics of the leafminer pest Tuta absoluta on tomato, Solanum lycopersicum

Abstract

The South American insect Tuta absoluta is a significant leaf-mining pest for tomato plants (Solanum lycopersicum). In the last fifteen years, it has invaded and rapidly expanded across most European and African countries. This poses increasing threats to key tomato-growing regions worldwide. Despite the global significance of crop damages caused by T. absoluta, existing models have primarily focused on the developmental growth at the individual level, with limited consideration for population and community-level interactions, especially the plant-pest relationship. Here we introduce and discuss an ecological, process-based, mathematical model that accounts for the interdependent dynamics between a population of the herbivorous insect and the tomato plants it feeds on. The model explicitly integrates the impacts of water and nutrients availability, as well as temperature, on the growth of both insect and plant populations. After calibrating the model using empirical data, we find that its simulations can replicate different observed patterns. Leveraging the mechanistic nature of our approach, we analyze the combined effects of various temperature, fertilization/irrigation (fertigation) and biocontrol scenarios on (i) crop growth and (ii) the overall health of the production system. This enables us to identify knowledge gaps and to discuss the effectiveness and trade-offs associated with different management policies.