Topic: The role of complementarity and antagonism among natural enemies in herbivore dynamics and biological control.
Dates: 6 November 2023 – 5 November 2026
CBGP supervisors: E. Frago & A. Xuereb
University: University of Montpellier, ED Gaia

Biological control is generally enhanced when natural enemies are more diverse, a relationship known as the biodiversity-biological control relationship. This relationship arises through the complementarity effect, whereby different enemies assist one another by preying on prey at different life stages or across different spatio-temporal scales. This positive effect can be lost when natural enemies engage in ‘antagonistic effects’, for example by preying on one another.

The aim of this PhD is to test hypotheses regarding the role of complementarity and antagonism between natural enemies in determining the potential for biological control. This PhD will include a significant experimental component, in which we will study in the laboratory the role of different combinations of natural enemies on the population dynamics of aphids and mites. To this end, we will collaborate with the company Biobest, which will supply all the necessary natural enemies. This PhD project also involves extracting data from the published literature to carry out a meta-analysis.

This PhD forms part of a wider ANR project entitled “EnemyCocktail: Designing mixtures of natural enemies for improved biological control”, which involves collaboration with theoretical modellers, ecologists and applied agronomists.