How Fertilizers Affect Antibiotic Resistance in Soil and Crops

Jenn Hoskins
29th July, 2024

How Fertilizers Affect Antibiotic Resistance in Soil and Crops

Image Source: Natural Science News, 2024

Key Findings

  • The study in China found that using 100% organic fertilizer led to the highest abundance of antibiotic resistance genes (ARGs) in soil
  • Using 100% chemical fertilizer resulted in the highest ARGs abundance in crops
  • A combined application of chemical and organic fertilizers could reduce the prevalence of ARGs in farming systems
Antibiotic resistance genes (ARGs) are a growing concern in agricultural systems, especially with the use of organic fertilizers. The Ministry of Agriculture and Rural Affairs, China, conducted a study to determine whether a combined application of chemical and organic fertilizers could mitigate the high prevalence of ARGs in soil and crops[1]. This study is crucial as it addresses the widespread issue of bacterial resistance contamination in farming systems, which poses a risk to both human health and environmental safety. The study examined the occurrence of ARGs under different fertilization regimes and explored the mechanisms by which micro-ecological shifts and geochemical factors influence the fate of ARGs in soil and crops. The results indicated that the soil ARGs abundance was highest when 100% organic fertilizer was used, while the highest ARGs abundance in crops was observed with 100% chemical fertilizer. Specifically, the application of organic fertilizers with more than a 50% ratio intensified the soil accumulation and migration of tetA, sul1, sul2, and macA genes. Interestingly, the study found that multidrug transporter, macA, and sul1 genes were co-shared between soil and crops, suggesting that these ARGs might be transferred across media through horizontal transfer. Horizontal transfer refers to the movement of genetic material between organisms in a manner other than traditional reproduction, often facilitated by mobile genetic elements like plasmids. To understand the relationship between soil microbial communities and ARG hosts, the researchers used Procrustes analysis. This analysis revealed a significant correlation between soil microbial community composition and ARG hosts. It also showed that the evolutionary pathway of soil microbes was congruent with antibiotic resistance, indicating that fertilizers affect soil ARG abundance mainly by altering soil microbial composition and their ecological evolutionary trajectories. The study also employed structural equations to demonstrate that soil nutrients and crop growth characteristics contributed significantly to the prevalence of crop ARGs. This finding highlights the complex interplay between soil chemistry, microbial ecology, and plant growth in determining the spread of ARGs. Previous studies have also highlighted the risk of ARGs in agricultural settings. For example, research has shown that poultry and bovine manure fertilization increases the concentration of antibiotics and heavy metals in soil, which in turn promotes the spread of ARGs[2]. Another study found that even organic farms, which typically use fewer chemicals, still had a high prevalence of tetracycline and sulfonamide resistance genes in soil[3]. Moreover, the transmission of ARGs in plant microbiomes has been identified as a significant pathway for the spread of antibiotic resistance, posing a threat to human health[4]. The current study expands on these findings by demonstrating that the type and ratio of fertilizers used can significantly influence the abundance and migration of ARGs in soil and crops. The results suggest that a combined application of chemical and organic fertilizers could potentially reduce the high prevalence of ARGs in farming systems, thereby offering a practical solution to curb antibiotic resistance contamination. In summary, this study by the Ministry of Agriculture and Rural Affairs, China, provides new insights into the prevalence of ARGs in soil and crops under different fertilization regimes. It underscores the importance of considering both microbial community composition and soil chemistry when developing strategies to mitigate the spread of antibiotic resistance in agricultural systems. By offering recommendations for fertilizer use, this research contributes to the ongoing efforts to manage antibiotic resistance in farming environments.

AgricultureEnvironmentBiochem

References

Main Study

1) Differential drivers on the occurrence of antibiotic resistance genes in agricultural soils and crops: Evidence from the different fertilization regimes.

Published 27th July, 2024

https://doi.org/10.1016/j.jenvman.2024.121998

Related Studies

2) Microbial and chemical pollutants on the manure-crops pathway in the perspective of "One Health" holistic approach.

https://doi.org/10.1016/j.scitotenv.2021.147411

3) Tetracycline and Sulfonamide Antibiotic Resistance Genes in Soils From Nebraska Organic Farming Operations.

https://doi.org/10.3389/fmicb.2018.01283

4) The dynamics and transmission of antibiotic resistance associated with plant microbiomes.

https://doi.org/10.1016/j.envint.2023.107986


Related Articles

An unhandled error has occurred. Reload 🗙