My research is focused on sensory and nutritional interactions in insect-plant and multitrophic systems consisting of: plants – plant feeding insects - parasitoids - predators.
Over 80% of plant feeding insect species and many parasitoid species are specialized feeders, whereas predators comprise both specialized and generalist species.Using comparative physiological, behavioural and ecological approaches, we study questions on the use of chemical information by insects, such as:
- how do specialists recognise their host plants and how do generalists discriminate preferred plants from less preferred plants?
- which chemical cues play a key role in host (plant) and prey searching and host (plant) acceptance?
- which chemoreceptors mediate these cues? How specific are these chemoreceptors?
- how is olfactory activity encoded and processed in the brain to generate behaviour? (cooperation with Hans Smid)
- what chemical changes take place in a plant when it is damaged by a plant-feeding insect and how does this affect plant-feeding insects, their parasitoids and predators? (cooperation with Marcel Dicke)
- are there fitness benefits to plants by emitting volatile information which attracts natural enemies? (cooperation with Marcel Dicke and Jeff Harvey)
I am also involved in projects studying the odour-mediated host selection behaviour of malaria mosquitoes (cooperation with Willem Takken).
Behavioural studies are the starting point of our work. We dispose over wind tunnels, olfactometers, a locomotion compensator (automated detailed walking track recording), videocamera’s, behavioural recording and analysis software and we use a range of feeding and oviposition assays on natural and artificial substrates. Behavioural observations raise questions on specificity and sensitivity of sensory perception which are addressed using electrophysiological techniques. Specificity and sensitivity of chemoreceptors that insects use to perceive plant-derived compounds are analysed by electrophysiological techniques: electroantennagrams (EAG) and single cell recordings on taste (‘tip-recording’) and olfactory neurons (surface-contact recording). For volatile plant compounds, sensory and chemical-analytical techniques are combined on-line, thereby enabling the efficient detection of individual chemicals that elicit sensory activity (coupled gas chromatography – electroantennography (GC-EAG)). Active chemicals eliciting attraction or acceptance are subsequently isolated and identified in several projects using a range of chemical analytical techniques (GC-MS, HPLC) under the guidance of behavioural assays, in close cooperation with chemists (Department of Organic Chemistry at WAU; Netherlands Institute of Ecological Research CTO-NIOO of KNAW; Department of Organic Chemistry, Technical University of Braunschweig; Institute of Zoology, Free University of Berlin).
Data from: Visual and odours cues: plant responses to pollination and herbivory affect the behaviour of flower visitors: Wageningen UR
Fitness consequences of indirect plant defence in the annual weed, Sinapis arvensis: Wageningen UR
Role of Large Cabbage White butterfly male-derived compounds in elicitation of direct and indirect egg-killing defenses in the black mustardFrontiers in Plant Science 6 (2015)SEPTEMBER. - ISSN 1664-462X - 9 p.
Feed conversion, survival and development, and composition of four insect species on diets composed of food by-productsPLoS ONE 10 (2015)12. - ISSN 1932-6203 - 20 p.
Insects Can Count: Sensory Basis of Host Discrimination in Parasitoid Wasps RevealedPLoS ONE 10 (2015)10. - ISSN 1932-6203 - 11 p.
Density-Dependent Interference of Aphids with Caterpillar-Induced Defenses in Arabidopsis: Involvement of Phytohormones and Transcription FactorsPlant and Cell Physiology 56 (2015)1. - ISSN 0032-0781 - p. 98 - 106.
Early herbivore alert matters: plant-mediated effects of egg deposition on higher trophic levels benefit plant fitnessEcology Letters 18 (2015)9. - ISSN 1461-023X - p. 927 - 936.
Rhizobacterial colonization of roots modulates plant volatile emission and enhances the attraction of a parasitoid wasp to host-infested plantsOecologia 178 (2015)4. - ISSN 0029-8549 - p. 1169 - 1180.
Plant-mediated effects of butterfly egg deposition on subsequent caterpillar and pupal development, across different species of wild BrassicaceaeEcological Entomology 40 (2015)4. - ISSN 0307-6946 - p. 444 - 450.
Nutrient utilisation by black soldier flies fed with chicken, pig, or cow manureJournal of Insects as Food and Feed 1 (2015)2. - ISSN 2352-4588 - p. 131 - 139.