| Title: | Habitat selection of a parasitoid mediated by volatiles informing on host and intraguild predator densities |
| Author(s): | Cotes B; Rannback LM; Bjorkman M; Norli HR; Meyling NV; Ramert B; Anderson P; |
| Address: | "Department of Plant Protection Biology, Integrated Plant Protection, Swedish University of Agricultural Sciences, P.O. Box 102, Vaxtskyddsvagen 3, Alnarp, SE-230 53, Sweden, Belen.cotes@slu.se" |
| DOI: | 10.1007/s00442-015-3326-2 |
| ISSN/ISBN: | 1432-1939 (Electronic) 0029-8549 (Print) 0029-8549 (Linking) |
| Abstract: | "To locate and evaluate host patches before oviposition, parasitoids of herbivorous insects utilize plant volatiles and host-derived cues, but also evaluate predator-derived infochemicals to reduce predation risks. When foraging in host habitats infested with entomopathogenic fungi that can infect both a parasitoid and its host, parasitoids may reduce the risk of intraguild predation (IGP) by avoiding such patches. In this study, we examined whether the presence of the entomopathogenic fungi Metarhizium brunneum and Beauveria bassiana in soil habitats of a root herbivore, Delia radicum, affects the behavior of Trybliographa rapae, a parasitoid of D. radicum. Olfactometer bioassays revealed that T. rapae avoided fungal infested host habitats and that this was dependent on fungal species and density. In particular, the parasitoid avoided habitats with high densities of the more virulent fungus, M. brunneum. In addition, host density was found to be important for the attraction of T. rapae. Volatiles collected from host habitats revealed different compound profiles depending on fungal presence and density, which could explain the behavior of T. rapae. We conclude that T. rapae females may use volatile compounds to locate high densities of prey, but also compounds related to fungal presence to reduce the risk of IGP towards themselves and their offspring" |
| Keywords: | Animals Beauveria/growth & development *Brassica/microbiology/parasitology Diptera/*physiology *Ecosystem Female Herbivory/*physiology Host-Pathogen Interactions Hymenoptera/*physiology Larva/physiology Metarhizium/growth & development Oviposition Plant R; |
| Notes: | "MedlineCotes, Belen Rannback, Linda-Marie Bjorkman, Maria Norli, Hans Ragnar Meyling, Nicolai V Ramert, Birgitta Anderson, Peter eng Research Support, Non-U.S. Gov't Germany 2015/05/07 Oecologia. 2015 Sep; 179(1):151-62. doi: 10.1007/s00442-015-3326-2. Epub 2015 May 7" |
