Simulated roots and host feeding enhance infection of subterranean insects by the entomopathogenic nematode Steinernema carpocapsae.
Steinernema carpocapsae can be effective against root-feeding insects despite its reputation as a sedentary ambusher. In pot experiments, using twigs as surrogate roots and pine weevil larvae as targets, we tested the hypothesis that roots serve as physical routeways and conduits of feeding-associated stimuli, thus enhancing the success of S. carpocapsae applied at the surface against subterranean hosts. Insect mortality was lowest (25%) in the absence of plant material, increased to 48% when twigs linked nematodes and insects, and further increased to 69% when the insects were allowed feed on the twigs. This is the first experimental support for the root-routeway hypothesis.
Ennis
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DE
Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland. darraghennis@gmail.com
Dillon
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AB
Griffin
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CT
D000818:Animals; D005247:Feeding Behavior / Q000502:physiology*; D006790:Host-Parasite Interactions / Q000502:physiology; D009348:Nematoda / Q000472:pathogenicity* / Q000502:physiology; D018517:Plant Roots; D048889:Weevils / Q000469:parasitology* / Q000502:physiology*