Exploiting entomopathogenic nematodes' sense of smell and manipulation of belowground trophic interactions enhance the control of the western corn rootworm

Insect herbivory induces synthesis and release of specific volatile compounds in plants. These volatiles have been shown to be highly attractive to natural enemies of the herbivores, such as predators, parasitic wasps or entomopathogenic nematodes. In maize, the volatiles emitted upon feeding by leaf- or root feeding arthropod herbivores have been particularly well studied in the laboratory. Among several, some key compounds mediating these so-called tritrophic interactions have been identified. Moreover, several genes and biochemical pathways responsible for the production of the emitted volatiles have been elucidated and described. These advances in understanding the volatile emission and its ecological signaling open novel ways to modify plant volatile blends in order to enhance their attractiveness to natural enemies. Beside this plant manipulation, different other approaches are explored in order to better control belowground herbivory exploiting belowground volatile signaling. For instance, entomopahtogenic nematodes have been selected for a better responsiveness to belowground cues or technics to lure the foraging insect herbivore are currently developed. Most of these manipulations could be simultaneously used for the benefit of agriculture.