n tropical conditions, the weed management in citrus orchards is particularly problematic when the fields are not mechanized. To reduce competition between trees and weeds, the producers use herbicides in excess of the permitted annual dose, particularly for glyphosate. In the current context of a demand of pesticide reduction, the challenge is to develop sustainable innovative systems. Our participatory method to design innovative sustainable cropping systems for citrus production led to the selection of different prototypes of weed management (Le Bellec et al., 2009). The aim of our study is to create a weed management-related indicator of ecosystem disturbance. Predatory mites of the family Phytoseiidae (Acari: Mesostigmata) were chosen for their potential as a bio-indicator of agricultural practice impacts on the agroecosystem functioning (Zacharda, 2001; Moonen and Barbari, 2008). (Résumé d'auteur