Multitrophic interactions: How plant defense is amplified by entomopathogenic nematode-infected cadavers

Abstract

Grasping the dynamics between plants and herbivores, as well as the defenses triggered by insects, may hold the key to eco-friendly pest management. Entomopathogenic nematodes (EPNs) have recently emerged as a promising biocontrol strategy, leading researchers to closely investigate how EPN-infected cadavers influence plant defenses. A recent study¹ revealed notable alterations in herbivore performance and a boost in defense chemicals in maize plants treated with these infected remains. These cadavers trigger the release of volatile organic compounds from plants, which discourage the herbivorous insect Spodoptera frugiperda from feeding and laying eggs while simultaneously attracting parasitic wasps. This activation of herbivore resistance in plants treated with EPN-infected cadavers is evident through increased levels of defense hormones, elevated enzyme activity, and the heightened expression of defense-related genes. The research also highlighted that different EPN species cause varying effects on plant responses and herbivore behaviors, indicating a need for further investigation into the specific secondary chemicals involved. Overall, these findings enhance our understanding of complex interactions between organisms above and below the ground and point toward potential sustainable agricultural practices.

Keywords

aboveground–belowground interactions / biological pest control / cadavers / entomopathogenic nematodes / multitrophic interactions

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2025 The Author(s). New Plant Protection published by John Wiley & Sons Australia, Ltd on behalf of Institute of Plant Protection, Chinese Academy of Agricultural Sciences.