Present address: Department of Entomology, University of Maryland, College Park, MD 20742, USA.
Lack of susceptibility of soil-inhabiting Platyprepia virginalis caterpillars, a native arctiid, to entomopathogenic nematodes in nature
Article first published online: 14 JUN 2011
© 2011 The Authors. Entomologia Experimentalis et Applicata © 2011 The Netherlands Entomological Society
Entomologia Experimentalis et Applicata
Volume 140, Issue 1, pages 28–34, July 2011
How to Cite
Karban, R., Hodson, A., Gruner, D. S., Lewis, E. E., Karban, J., Joseph, M., Mata, T. and Strong, D. R. (2011), Lack of susceptibility of soil-inhabiting Platyprepia virginalis caterpillars, a native arctiid, to entomopathogenic nematodes in nature. Entomologia Experimentalis et Applicata, 140: 28–34. doi: 10.1111/j.1570-7458.2011.01133.x
Present address: Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309, USA.
- Issue published online: 14 JUN 2011
- Article first published online: 14 JUN 2011
- Accepted: 28 April 2011
- population regulation;
- Heterorhabditis marelatus;
- Steinernema feltiae;
- wooly bear;
- pest control
Entomopathogenic nematodes (EPNs) can kill and regulate populations of soil-inhabiting insects, but studies evaluating these interactions in native ecosystems are rare. The objective of this study was to examine the effects of EPNs on a non-agricultural caterpillar, Platyprepia virginalis (Boisduval) (Lepidoptera: Arctiidae), under natural conditions. Platyprepia virginalis caterpillars live in litter on the soil surface feeding beneath bush lupine during summer, autumn, and winter. Initial laboratory assays revealed that the caterpillars were vulnerable to at least two species of EPNs with which they co-occur in the coastal prairie in northern California (USA). In contrast to laboratory assays, caterpillars survived exposure to prairie soil containing EPNs under natural conditions in field assays. To better understand the divergence between laboratory and field results for this native caterpillar, we used sentinel insects [Galleria mellonella L. (Lepidoptera: Pyralidae)] to identify particular locations where EPNs were present in the field. Platyprepia virginalis caterpillars were caged at these sites but again showed no evidence of susceptibility to EPNs. Platyprepia virginalis caterpillars reduce their exposure to EPNs by spending their time in and above the litter rather than contacting the soil when given the choice in nature. We conclude that P. virginalis is unlikely to serve as a reservoir for EPNs and that nematodes are unlikely to be important mortality factors for P. virginalis in this natural system.