Développement d’une bioformulation à base d’huiles essentielles de Citrus aurantium et Rosmarinus officinalis pour le biocontrôle multi-stade de la tomate contre Alternaria sp. et Sclerotinia sp.

Abstract

Tomato (Solanum lycopersicum L.) is an essential crop but is strongly limited by fungal diseases such as Alternaria sp. and Sclerotinia sp., responsible for significant losses in both production and post-harvest conservation. This study is part of a biocontrol approach and evaluates the effectiveness of formulations based on essential oils obtained by hydrodistillation from Rosmarinus officinalis and the peel of Citrus aurantium, as an alternative to synthetic fungicides. The experiment is structured into three parts: an in vitro study of the direct action on fungal structures, a preventive seed coating treatment targeting Alternaria sp. at the seedling stage, and a preventive fumigation treatment applied to fruits before inoculation targeting Sclerotinia sp. during post-harvest storage. The results show morphological alterations in hyphae and conidia, indicating a direct antifungal effect. The treatments improve plant growth, chlorophyll content, biomass, and phenolic compound levels, while reducing disease development. During post-harvest storage, fumigation effectively limits infection and preserves fruit quality, with optimal efficacy observed at 0.4% (v/v) during one hour of preventive treatment. These findings confirm the biocontrol potential of this plant-based formulation.