Résumé
Soil is a finite and dynamic living resource. Soil health arises from multiple interactions between physicochemical and biological components, including microbial communities, of primary importance for soil functioning. Facing the threat of soilborne pathogens, cultural practices, as "ecological" crop protection methods, are more and more used. Their aim is to modify the soil microbial equilibrium. In order to measure soil health and to propose cultural practices to improve it, it is necessary to define indicators of soil health. The aim of this study is to propose indicators of soil health, through the evaluation of the impact of two cultural practices (amendment with composted cattle manure and biofumigation) on physicochemical and biological characteristics of the soil, in relation with the phytosanitary quality of a carrot crop. Multivariate analyses, associated with co-inertia analyses, revealed that some descriptors of the soil could be considered as potential indicators of soil health. In particular, these descriptors are associated with biofumigation, which enhance the soil suppressiveness to Rhizoctonia solani diseases. Descriptors could then be integrated in a minimum data set of indicators of soil health. This study could be continued by the confirmation of the interest of these descriptors, the construction of an indicator, and its validation.