Aphids as crop pests

In recent decades, the development of new concepts in ecology, such as ecosystem services (Losey and Vaughan, 2006), landscape ecology, food web complexity (Gagic et al., 2011), apparent competition and mutualism, has changed our concepts of pest control. Consequently, the theoretical bases underlying the biological control of aphids have evolved towards a more integrated approach. The intensification of agriculture has led to an oversimplification of agricultural systems, and therefore also of the associated trophic systems. The extreme case is that of glasshouses, in which crops are increasingly grown hydroponically, without soil and fed with nutrient solutions. These simplified environments are particularly…