Cotesia glomerata attacking Pieris brassicae larvae

Marcel Dicke's research

Insects and mites are small organisms that are very well informed about their environment. They can use chemical cues such as volatiles or non-volatile cues to obtain information on the presence of e.g. their food, competitors, sexual partners, and enemies. Insects are members of complex communities consisting of e.g. plants, herbivorous, carnivorous arthropods and pollinators.

The ecology of body odour

Herbivorous and carnivorous arthropods use plant volatiles when foraging for food. In response to herbivory plants emit a chemical blend that may be quantitatively and qualitatively different from the blend emitted when intact (plant ‘cry for help’). This induced volatile blend alters the interactions of the plant with its environment. It has been well established that carnivores (predators and parasitoids) are attracted by the volatiles induced by their herbivorous victims. Apart from a benefit from attracting carnivores, the induced volatiles can have a serious cost because herbivores may be attracted. Yet, whether the attracted herbivores settle on the plant that emits the volatiles may depend on the presence of herbivore and/or carnivore cues that indicate that the plant is a competitor- and/or enemy-dense space. Thus, the benefit of emission of induced volatiles is likely to depend on environmental conditions. Whether plants can influence the emission of the induced volatiles, taking the prevalent environmental conditions into account, is an interesting question that needs to be addressed. The induced volatiles may also affect interactions of the emitting plant with its neighbours, e.g. through altered competitive ability or by the neighbour exploiting the emitted information. This is a topic that should receive more attention.We investigate the ecology of infochemicals through a multidisciplinary approach, from genes to the community.

Apart from research on infochemicals in plant-arthropod interactions, we have also started a study on the role of infochemicals in chicken-mite interactions and the potential for exploiting the infochemicals to control mites that attack chicken.

Our research focuses on:

  1. Chemical ecology of multitrophic interactions: what chemicals are induced in plants by herbivory, what is their effect on arthropod behaviour, and how do the cues affect interactions in the community?
  2. Plant-mediated interactions among microbes, herbivorous insects, carnivorous insects and pollinating insects.
  3. Molecular ecology of multitrophic interactions: what signal-transduction pathways are induced in plants by herbivory, what genes are induced, what transcriptome changes occur in response to attack by different types of organisms?
  4. Behavioural ecology of predator avoidance: how do predator cues affect prey behaviour?

Dicke & Baldwin, Trends in Plant Science 2010
Dicke & Baldwin, Trends in Plant Science 2010