Microbial Biodegradation of Sulfonylurea Herbicides in Agricultural Soils

The sulfonylurea class of herbicides is widely applied at low doses to control broadleaf weeds in diverse cropping systems, yet residues can persist in soil and water, posing risks to non‐target organisms and subsequent crops. Microbial biodegradation constitutes the primary removal pathway, whereby diverse bacterial and fungal taxa enzymatically cleave the sulfonylurea bridge and associated ester bonds, yielding polar metabolites that are generally less phytotoxic. Degradation kinetics often follow first‐order models, with rates modulated by soil pH, moisture, organic matter content and the presence of co‐substrates. Repeated herbicide applications can select for adapted microbial communities, accelerating dissipation in some contexts. Recent advances integrate genomics, transcriptomics and metabolomics to uncover catabolic genes and regulatory networks that govern herbicide breakdown. Synergistic strategies—combining specialised microbial consortia with plant roots or agricultural by-products—have shown promise in enhancing in situ degradation, offering pathways to mitigate environmental accumulation and maintain soil health globally.

Research from Nature Portfolio

Recent studies have employed transcriptomic analysis to elucidate microbial responses to nicosulfuron exposure. Investigations into a soil-borne Pseudomonas strain revealed large-scale differential gene expression in transporters, sulphur metabolism and central carbon pathways upon herbicide stress. Upregulation of glycolysis and glyoxylate cycle genes corresponded with increased production of acid metabolites, notably oxalic acid, which facilitated nicosulfuron cleavage. This work highlights the role of metabolic adaptation and acidolysis in microbial detoxification of sulfonylurea compounds, underscoring the integration of omics approaches to uncover degradation mechanisms.

Microbial Biodegradation of Sulfonylurea Herbicides in Agricultural Soils publication trend

The graph below shows the total number of articles in microbial biodegradation of sulfonylurea herbicides in agricultural soils across all publications each year (not limited to Nature Index journals).

Technical terms

Sulfonylurea herbicides: A class of high-potency herbicides characterised by a sulfonylurea bridge, used to control broadleaf weeds at low application rates.

Biodegradation: The microbial breakdown of chemical compounds into simpler, often less toxic, products through enzymatic activity.

Co-metabolism: The transformation of a non-growth substrate by microorganisms in the presence of a utilizable carbon or energy source.

Esterase: An enzyme that catalyses the hydrolysis of ester bonds, critical in cleaving portions of the herbicide molecule.

Biofilm: A structured microbial community embedded in an extracellular matrix, which can influence degradation kinetics and pollutant adsorption.

References

1. Transcriptomic response of Pseudomonas nicosulfuronedens LAM1902 to the sulfonylurea herbicide nicosulfuron. Scientific Reports (2022).
2. Characterization and genomic analysis of a bensulfuron methyl-degrading endophytic bacterium Proteus sp. CD3 isolated from barnyard grass (Echinochloa crus-galli). Frontiers in Microbiology (2022).
3. Plant and Microorganism Combined Degradation of Bensulfuron Herbicide in Eight Different Agricultural Soils. Agronomy (2022).
4. Effect of Repeated Application of Sulfonylurea Herbicides on Sulfosulfuron Dissipation Rate in Soil. Agronomy (2020).