Work

Plant-based biofungicides: A balance between protection and soil health preservation

Year: 2026

Type: article

Abstract: Plant-based biocontrol products are promoted as sustainable alternatives to synthetic pesticides, yet their potential non-target effects on soil microbial communities remain poorly investigated. Because these communities play a central role in soil functioning, assessing their responses to such products is essential. In this study, we evaluated the impact of a plant-based biocontrol product tested as a crude extract (Ext) and a formulated version (Form), as well as the triazole fungicide mefentrifluconazole (Fung), on soil microbial communities. Treatments were applied at the recommended dose (×1) and a tenfold higher dose (×10), used as a high-exposure scenario, in a controlled incubation experiment. Soil enzymatic activities, community-level physiological profiling (CLPP), and carbon mineralization were monitored over time. The fungicide caused significant but transient effects on soil enzymatic activities, whereas microbial functional diversity showed only trends toward differences compared with the biocontrol treatments. However, multi-enzymatic indexes indicated a significant decline in soil enzymatic functioning 63 days after fungicide application. CLPP analysis suggested a slight reduction in overall microbial metabolic activity in the Fung ×10 treatment, with variations in amino acid substrate utilization patterns. A trend toward higher carbon mineralization was observed during the first 10 days under the Fung ×10 treatment. In contrast, at the ×1 dose, biocontrol treatments showed limited effects on carbon mineralization, with Form and Ext showing responses comparable to the control. Overall, plant-based biocontrol treatments showed limited effects on soil microbial functioning under the tested conditions, whereas the synthetic fungicide induced short-term functional disruptions. These findings highlight the importance of considering soil microbial responses in the environmental assessment of plant-protection products.

Source: Applied Soil Ecology

DOI: 10.1016/j.apsoil.2026.107518