Evaluation of the Impact of Flutriafol on Soil Culturable Microorganisms and on Soil Enzymes Activity

Fungicides play a role in managing plant diseases but raise concerns about environmental impact, emphasizing the need to understand and minimize their effects on non-target ecosystems. Flutriafol is a fungicide used to combat fungal diseases in crops. It has two enantiomers that exhibit different levels of efficacy and environmental impact. This study focuses on evaluating the effects of different doses of flutriafol on soil microorganism populations and enzyme activity and the possible specificity of enantiomer interactions with soil enzymes by combining experimental and computational approaches. The effects of different doses of flutriafol on the population of microorganism and on the activity of soil enzymes were experimentally assessed. Molecular docking of the enantiomers with soil enzymes was used to assess the possible stereoselectivity of the interactions. Regardless of the dose used (normal dose recommended by the manufacturer for cereal crops, half this dose, and double dose), flutriafol had no significant impact on soil microbial communities or on catalase activity. The half dose of flutriafol produced increases in the activity of dehydrogenases (8%), phosphatases (26%), and urease (33%) during the first 7 days of incubation. Molecular docking showed that both enantiomers were able to bind to the active sites of dehydrogenases and phosphatases. The average value of the interaction energy observed for ( R )-flutriafol with dehydrogenases was −7.85 kcal/mol, compared to −7.45 kcal/mol for the interaction of ( S )-flutriafol with these enzymes. Similarly, the interaction energy obtained for the interaction of ( R )-flutriafol with phosphatase was −9.16 kcal/mol, compared to −9.04 kcal/mol for the interaction of ( S )-flutriafol with this enzyme. This study confirms the need to implement optimized application practices when using flutriafol by considering the enantiomer that is most effective on the target organism and less toxic to non-target ecosystems.