Multitrophic effects of belowground parasitoid learning

Authors: Willett, Denis; Alborn, Hans; STELINSKI, LUKASZ - University Of Florida

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/18/2017
Publication Date: 5/18/2017
Citation: Willett, D.S., Alborn, H.T., Stelinski, L.L. 2017. Multitrophic effects of belowground parasitoid learning. Scientific Reports. 7(1):1-10. doi:10.1038/s41598-017-02193-2.

Interpretive Summary: Learning gives organisms the ability to quickly adapt to changing conditions in their environment. Learned tool use in primates, for example, allows individuals to take advantage of otherwise unavailable resources. Learning in one species can have effects on other species and on the community. Here scientists at the Center for Medical, Agricultural, and Veterinary Entomology USDA-ARS in Gainesville, FL in collaboration with scientists at the University of Florida show that learning in belowground entomopathogenic nematodes has cascading multitrophic effects on their hosts, other nematodes, and nematophagous fungal predators. In addition to quantifying these effects, we show that social behavioral plasticity in these belowground parasitoids can amplify signaling by plant defense pathways and results in an almost doubling of insect herbivore infection by entomopathogenic nematodes. Cumulatively, these effects point to the critical role of plant signaling in regulating community structure while suggesting an equally important role for behavioral plasticity in shaping community dynamics. Importantly, these results point to broad opportunities for enhancing biological control of subterranean pest species by manipulating entomopathogenic nematode learning. By exposing entomopathogenic nematodes to plant volatiles, we can enhance targeting and control of pests in dynamic belowground communities.

Technical Abstract: The ability to learn allows organisms to take advantage of dynamic and ephemeral opportunities in their environment. Here we show that learning in belowground entomopathogenic nematodes has cascading multitrophic effects on their hosts, other nematodes, and nematophagous fungal predators. In addition to quantifying these effects, we show that social behavioral plasticity in these belowground parasitoids can amplify signaling by plant defense pathways and results in an almost doubling of insect herbivore infection by entomopathogenic nematodes. Cumulatively, these effects point to the critical role of plant signaling in regulating community structure while suggesting an equally important role for behavioral plasticity in shaping community dynamics.