Abstract

Despite the recent knowledge on entomopathogenic nematodes (EPNs), there are still biological aspects that should be considered to fully understand these peculiar organisms, which live in diverse and changing environments. EPNs and their symbiont bacteria should be taken as holobionts, where the roles and functions that each symbiont plays are fundamental to a good performance as a biological control agent. We propose that EPNs must face three different and complex environments during their life cycle: the soil, the living host and the dead host. We present detailed aspects of their life cycle. Their biological and ecological success in relation to the symbiotic interaction with the bacteria and adapting to the challenges imposed by each environment indicates the enormous plasticity and adaptability of these organisms. Thus, considering these important features in future studies will allow us to optimize EPN efficacy as biological control agents under field conditions.