Food Webs and Multiple Biotic Interactions in Plant-Herbivore Models

Authors: CORKET, EMMANUEL - Bordeaux University; GIFFARD, BRICE - Bordeaux University; SFORZA, RENE - European Biological Control Laboratory (EBCL)

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 12/31/2016
Publication Date: 1/30/2017
Citation: Corket, E., Giffard, B., Sforza, R. 2017. Food Webs and Multiple Biotic Interactions in Plant-Herbivore Models. Book Chapter. In N. Sauvion, P-A. Calatayud, D. Thiéry (Volume Eds), Advances in Botanical Research series : Vol 81. Insect-Plant Interactions in a Crop Protection Perspective. Elsevier, GBR. p. 111-138.

Interpretive Summary: To fully understand plant-insect interactions, one should consider the entire ecological system in which such organisms are living. This includes all the biotic relationships that occur among species in the ecosystem, as well as the abiotic relationships with the environment, including the effects that species have on their environment. Plant-insect interactions are controlled by the same fundamental processes, regardless of whether they are in natural ecosystems or highly managed agrosystems. The difference lies in the number of organisms involved in the system and the complexity of those interactions. In this chapter we describe the many types of trophic interactions (those that involve feeding) known to occur between insects and plants. Concepts and examples are taken primarily from ecological studies, i.e. from ecosystems that are much more complex than croplands or intensively managed agrosystems. We hope that this approach will help us to understand how an agronomic system may function in a context of high biological diversity.

Technical Abstract: Trophic relationships between plants and insects are not confined to biological interactions such as herbivory (i.e. direct consumption of one primary producer by a predator), in an ecological approach, many other interactions, trophic or even non trophic, may influence plant herbivory by insects. These interactions are related to the complexity and the diversity of the fauna and flora. Plants and insects own to food webs, characterised by properties emerging from the identity of organisms and from the organisation of the links they develop with each other. These organisms can be considered both taxonomic, and as functional units of biodiversity highlighting the complexity of food webs. Insects can be predated (e.g. by other arthropods or birds), parasitized and compete for resources. Plant competition and availability of resources for primary producers may also influence the relationship between plants and their consumers. The inclusion of predation mechanisms in plant-insect interactions lead to the theory of trophic cascades which advanced our understanding of the process of herbivory by insects. Ecological theories give a framework to assess the way by which these biotic interactions may be controlled in ecological systems. Trophic cascades provide also biological tools for the management of agro-ecosystems, especially for biological control of herbivores and the promotion of biodiversity. Biological interactions within food webs may also be non-trophic, and alter plant-insect herbivory. Intraguild competition, interference, abiotic resources, microclimate and changes in animal behaviour are some of the drivers which may influence plant and insects, and thus their trophic relationships.