Harmonising control: understanding the complex impact of pesticides on parasitoid wasps for enhanced pest management

The pervasive application of chemical pesticides is globally recognised for its effectiveness and cost-efficiency in controlling pest populations. However, this approach has inadvertently impacted a diverse array of organisms, including humans and beneficial insects, notably those that naturally regulate pest populations. This review synthesises current research on both the direct and indirect effects of pesticides on parasitoid wasps. These wasps are vital for the biological control of herbivorous insect populations through a top-down approach. Here, we examine the complex ways in which pesticides may compromise the parasitoids' life history traits, interfere with their host-seeking behaviour, and modulate the immune responses of the hosts that in turn affect parasitoid success. Gaining a more nuanced understanding of these dynamics is crucial for the development of integrated pest management strategies that aim to reconcile the use of chemical pesticides with biological control approaches, ultimately fostering more sustainable agricultural practices.