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  1. Bad or good food, that’s the question!

    Stage
    A study on the effects of stoichiometric constraints on rotifer populations

  2. Bad or good food, that’s the question!

    A study on the effects of stoichiometric constraints on rotifer populations

  3. Comparing insect communities on native Dutch wild mustard plants over a growing season

    Stage
    Host-plant suitability and quality for herbivore (and possibly natural enemy) development is determined by the presence of sufficient levels of nutrients and concentrations of adverse metabolites such as specific secondary plant compounds and digestibility reducers. In nature, these characteristics are dynamic and can change within individual plants over the course of a growing season. Many species of multivoltine insects (insects have more than one generation per year) are known to attack short-lived annual plants i.e. plants that are present for only 1or 2 months in the field. These short-lived plants may germinate and grow at different times and/or locations during the growing season. In this situation, each herbivore generation is faced with the challenge of leaving the natal patch to find and lay eggs on a different plant species that may be growing some distance from where they themselves developed. At the same time, the quality of the different food plant species on which they feed and grow over the spring and summer seasons may also be highly variable.

  4. Comparing insect communities on native Dutch wild mustard plants over a growing season

    Host-plant suitability and quality for herbivore (and possibly natural enemy) development is determined by the presence of sufficient levels of nutrients and concentrations of adverse metabolites such as specific secondary plant compounds and digestibility reducers. In nature, these characteristics are dynamic and can change within individual plants over the course of a growing season. Many species of multivoltine insects (insects have more than one generation per year) are known to attack short-lived annual plants i.e. plants that are present for only 1or 2 months in the field. These short-lived plants may germinate and grow at different times and/or locations during the growing season. In this situation, each herbivore generation is faced with the challenge of leaving the natal patch to find and lay eggs on a different plant species that may be growing some distance from where they themselves developed. At the same time, the quality of the different food plant species on which they feed and grow over the spring and summer seasons may also be highly variable.

  5. De rol van secundaire plantenstoffen in de smalle weegbree in resistentie tegen pathogenen en herbivoren

    Stage
    Secundaire plantenstoffen kunnen een rol spelen bij afweer tegen zowel herbivoren als fytopathogene schimmels. In natuurlijke populaties wordt vaak een grote mate van genetische variatie in (constitutieve) gehaltes aan secundaire plantenstoffen gevonden. Een algemeen aanvaarde verklaring hiervoor is dat er kosten verbonden zijn aan deze vorm van afweer: waardgenotypen met hoge gehaltes hebben een selectief voordeel bij hoge selectiedruk door herbivoren, maar genotypen met lage gehaltes, d.w.z. lage kosten, bij een lage selectiedruk.

  6. Ecologische en evolutionaire interacties tussen waardplant, pathogene schimmel, en herbivoor insect: aanpassingen in een complexe wereld

    Stage
    Een groot deel van de potentiële reproductie van planten in natuurlijke populaties gaat verloren door toedoen van pathogenen en herbivoren. Twee anjerachtigen, Silene alba en S. dioica worden in ons land bijvoorbeeld geïnfecteerd door de brandschimmel Ustilago violacea, die de vruchtbeginsels van geïnfecteerde bloemen aborteert, en de helmhokjes gebruikt om haar eigen sporen in te produceren.

  7. How do soil micro-organisms affect the chances of woodland expansions during water pulses?

    Stage
    Woodland expansion in arid environments occurs episodically during wet years. Recent research indicates that tree seedling growth rate and survival is crucial to explain the differences across ecosystems and that soil microorganisms likely play a crucial role.

  8. How do soil micro-organisms affect the chances of woodland expansions during water pulses?

    Woodland expansion in arid environments occurs episodically during wet years. Recent research indicates that tree seedling growth rate and survival is crucial to explain the differences across ecosystems and that soil microorganisms likely play a crucial role.

  9. Lifetime reproductive success in two secondary hyperparasitoid wasps, Lysibia nana and Gelis agilis

    Stage
    Hyperparasitoids are insects that develop on, or in another parasitoid species. Secondary hyperparasitoids attack primary parasitoid hosts (usually their cocoons) that have already emerged from the secondary herbivore host. In spite of their potential importance in affecting the dynamics of plant-herbivore-parasitoid systems (over three trophic levels), little is still known about the biology and life-history of secondary hyperparasitoids (in the fourth trophic level).

  10. Lifetime reproductive success in two secondary hyperparasitoid wasps, Lysibia nana and Gelis agilis

    Hyperparasitoids are insects that develop on, or in another parasitoid species. Secondary hyperparasitoids attack primary parasitoid hosts (usually their cocoons) that have already emerged from the secondary herbivore host. In spite of their potential importance in affecting the dynamics of plant-herbivore-parasitoid systems (over three trophic levels), little is still known about the biology and life-history of secondary hyperparasitoids (in the fourth trophic level).