Simpler soil assay tracks microbial phosphorus
Researchers refined a laboratory method for measuring DNA-bound phosphorus in soil, making it cheaper and simpler without losing accuracy. They removed unnecessary enzyme steps but kept ultrafiltration, then tested the approach on 32 soils from the United Kingdom. The improved test may help clarify how microbes recycle phosphorus and support more sustainable fertilizer use.
Phosphorus supports crops, yet accessible reserves are finite, so understanding its soil transformations matters. DNA-bound phosphorus is one component of organic phosphorus tied to soil microbes, which continually cycle nutrients. The team simplified an existing assay by dropping enzyme steps while retaining ultrafiltration, then checked it across 32 United Kingdom soils.
In the sampled soils, DNA-P represented only a minor fraction of organic phosphorus. Its levels nonetheless tracked pH, microbial biomass phosphorus, organic matter, and water-dissolved phosphorus. That pattern points toward living microorganisms and the active phosphorus cycle rather than long-lived, stable reserves.
A cheaper, simpler assay may make it easier for soil scientists and agricultural advisers to monitor biologically active phosphorus. That could improve fertilizer guidance, potentially reducing waste and environmental damage. Farmers might gain clearer information about soil microbial contributions to nutrient availability, while food systems could see gradual efficiency gains. The impact would likely depend on further validation and how readily the method is adopted.