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The objective of this study was to determine the efficiency of the microbial rhizosphere ( Canavalia ensiformis ) in the phytoremediation of sulfentrazone using quantification methods (CO2 evolution, microbial biomass carbon, and metabolic quotient) and identification of bacteria (PCR-DGGE technique). The experiment was conducted in a completely randomized design, in a 2x4 factorial scheme, with four replications. The treatments were composed of rhizospheric soil (cultivated with C. ensiformis ) and non-rhizosphere soil (uncultivated soil); and four levels of contamination by sulfentrazone (0, 200, 400, and 800 g ha -1 a.i.). The microbiota associated with the rhizosphere of C. ensiformis efficiently reduced sulfentrazone residues in the soil, with better performance at the dose of 200 g ha -1 a.i. Using the PCR-DGGE technique allowed the distinction of two profiles of bacteria in the rhizospheric activity of C. ensiformis . The second bacterial profile formed was more efficient in decontaminating soil contaminated with sulfentrazone residue. The microbiota associated with the rhizosphere of C. ensiformis has an efficient profile in decontaminating soils with residues equivalent to 200 g ha -1 a.i. the herbicide sulfentrazone.

Soil is one of the largest reservoirs of microbial diversity in nature. Although soil management is vital for agricultural purposes, intensive practices can have a significant impact on fertility, microbial community, and resistome. Thus, the aim of this study was to evaluate the effects of an intensive soil management system on the chemical attributes, composition and structure of prevalent bacterial communities, and presence and abundance of antimicrobial resistance genes (ARGs). The chemical characterization, bacterial diversity and relative abundance of ARGs were evaluated in soils from areas of intensive vegetable cultivation and forests. Results indicate that levels of nutrients and heavy metals were higher in soil samples from cultivated areas. Similarly, greater enrichment and diversity of bacterial genera was detected in agricultural areas. Of the 18 target ARGs evaluated, seven were detected in studied soils. The oprD gene exhibited the highest abundance among the studied genes and was the only one that showed a significantly different prevalence between areas. The oprD gene was identified only from soil of the cultivated areas. The bla SFO , erm(36), oprD and van genes, in addition to the pH, showed greater correlation with in soil of cultivated areas, which in turn exhibited higher contents of nutrients. Thus, in addition to changes in chemical attributes and in the microbial community of the soil, intensive agricultural cultivation systems cause a modification of its resistome, reinforcing the importance of the study of antimicrobial resistance in a One Health approach., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)