Flowers to increase the effectiveness of biological control

Conservation biological control consists of manipulating plant diversity in order to increase the number and effectiveness of natural enemies of crop pests. Juan Sorribas and Joan Van Baaren, from the UMR Ecobio, are studying this practice through the European FLORALWOOD project.
Aphidius matricariae sur  fleur de sarrasin ©INRA, Bernard Chaubet

Context

Agricultural production systems need to adapt to climate change in a structured and coordinated way. More and more private companies are offering consulting services to farmers and forest managers. The aim is to propose pest control methods that use fewer pesticides, while maintaining the productivity and profitability of production systems.

However, these practices, which are based on conservation biological control, are mainly empirical. It is now necessary to rationalise them through a better understanding of the underlying ecological mechanisms, i.e. the interaction between functional biodiversity, microclimate and pest regulation.

Objective

In this context, the Floralwood project aims to evaluate the pest regulation service provided by the evolutionary and functional diversity of plants. This is all the more necessary as climate change is increasing the risks of pest outbreaks in terms of both frequency and intensity, which are expected to become more frequent and more pronounced.

The project aims to test the following two hypotheses:

  1. greater floristic diversity can promote the emergence of richer communities at all trophic levels. In the context of more stressful climatic conditions, these richer communities will provide a more consistent ecosystem service of pest suppression
  2. Higher plant diversity may be able to increase the resistance of pests' natural enemies to thermal stresses, by providing them with more diverse trophic resources across seasons and space. As a first step, it is necessary to determine which plant species to assemble that are most effective for natural enemies. The most useful flowers as a food source will then be tested in a greenhouse set-up in Spain, in a context of hot thermal stress

This project will provide:

  • a reference on the characteristics of plants that should be combined in floral mixtures to favour the natural enemies of pests in the different crops
  • practical recommendations for the implementation of conservation biological control methods

Identity card

European project FLORALWOOD - HORIZON 2020 Programme - Marie S. Curie Action Curie Action

Institution: Université de Rennes 1

Beneficiary: Juan SORRIBAS

Name of the Scientific Leader: Joan VAN BAAREN
Laboratory / UMR: Ecosystèmes, Biodiversité, Evolution (ECOBIO) - UMR CNRS 6553
Project duration: From 15/01/16 to 14/01/18 (2 years)