Food selection and fitness optimisation in insects
Author
Summary, in English
Plants producing proteinase inhibitors experience reduced attacks by herbivores thus the effect on predators feeding on the herbivores was studied. The herbivorous caterpillar Helicoverpa armigera was fed an artificial diet containing a proteinase inhibitor and the ground beetle Harpalus affinis was fed with H. armigera. H. affinis reduced its feeding when the caterpillars had been fed the proteinase inhibitor containing diet. This indicates that changes in food quality at the plant trophic level cascaded to the predator trophic level.
In spite of the many laboratory studies we still lack knowledge of selection of food in the field for this insects. A PCR-based method to detect DNA of ingested food species has been developed. Diversity of fungi found in the gut of collembolans was low compared to that of whole animals. This might be due to the dissection method where the head with mouthparts and the uppermost part of the gut was discharged, which presumably contains most undigested fungal material. This method will make it possible to study food selective behaviour of cryptic soil organisms in the future.
Department/s
Publishing year
2002
Language
English
Document type
Dissertation
Publisher
Helene Bracht Jørgensen, Lund University, Dep. of Animal Ecology, Ekologihuset, Sölvegatan 37, S-223 62 Lund, Sweden,
Topic
- Ecology
Keywords
- food preference
- nested PCR
- fungal DNA
- växtparasitologi
- plant parasitology
- Entomology
- Entomologi
- fungi
- seeds
- ground beetles
- collembolans
Status
Published
Research group
- Soil Ecology
Supervisor
- [unknown] [unknown]
ISBN/ISSN/Other
- ISBN: 91-7105-182-1
Defence date
13 December 2002
Defence time
10:15
Defence place
Blå Hallen, Ekologihuset, Sölvegatan 37, Lund
Opponent
- Herman A. Verhoef (Prof)