Bio-Phage UK is a 36-month, collaborative R&D project focused on reducing fertiliser-related greenhouse gas emissions in UK dairy forage systems.
Bio-phage UK will test whether biological inputs and novel phage technology can help dairy farms to reduce reliance on synthetic nitrogen fertiliser by around 50%, delivering measurable reductions in nitrous oxide (N₂O) emissions linked to fertilised soils, while maintaining (or improving) forage performance.
The project brings together on-farm trial delivery, biological product development, and independent scientific capability (emissions monitoring, life cycle assessment and soil microbiome analysis). Trials will be delivered on three commercial dairy farms with supporting glasshouse work to refine dose rates and application strategies.
Bio-Phage UK is funded through Defra’s Farming Innovation Programme, delivered with Innovate UK.
At a glance
Duration: 36 months
Farming system focus: dairy grassland and forage (ryegrass, herbal leys, wholecrop)
Locations: three commercial dairy farms
Trial scale: 12 treatments, replicated across sites and seasons
Core aim: ~50% reduction in synthetic nitrogen use, while maintaining forage performance
Measurement: field emissions monitoring, soil/forage analysis, metagenomics and full life cycle assessment (LCA)
Dissemination: full farmer engagement programme, including on-farm events and knowledge exchange outputs
The knowledge gap
Biological inputs are increasingly discussed as tools to support nutrient efficiency and soil function. However, independent, farm-scale evidence is still limited, particularly evidence that combines agronomic performance, emissions outcomes and cost-effectiveness in real dairy forage systems.
At the same time, novel approaches such as phage-based treatments are emerging in agriculture. Yet they are not yet widely validated as practical tools for reducing nitrification-driven nitrogen losses under commercial conditions.
Bio-Phage UK is designed to address both gaps by testing biological inputs and a phage-based soil treatment in a robust, transparent programme, with measurements designed to explain not only whether something works, but why.
What’s being trialled
Bio-Phage UK will test a combined “dual biological” approach that brings together:
- A suite of biological inputs used within forage systems
These include foliar-applied products such as seaweed extracts, fish hydrolysate and humates, alongside a slurry additive. The inputs are intended to support plant and soil processes linked to nutrient use efficiency and resilience, and to help reduce reliance on synthetic nitrogen without compromising output. - BIOCAT (phage-based soil treatment)
BIOCAT is a phage-based soil treatment designed to selectively suppress nitrifying bacteria and support beneficial microbial communities. The objective is to reduce nitrification-driven nitrogen losses — a key pathway linked to both reduced nitrogen efficiency and increased N₂O emissions.
The project will test individual inputs and combinations to understand which approaches are most effective, and whether combinations are additive, synergistic or counterproductive under different farm conditions.
Trial design and delivery
The core programme consists of multi-year field trials on three commercial dairy farms. Trials will compare 12 treatments across common dairy forage crops and rotations, including ryegrass, herbal leys and wholecrop systems. Trial work will be supported by controlled-environment (glasshouse) trials at the University of Nottingham to help refine application rates and mixing strategies and improve reliability across sites and seasons.
On-farm delivery is co-designed with participating farmers and implemented through regular farm visits, consistent monitoring protocols and structured feedback. This ensures the work remains grounded in commercial reality, including timeliness of operations, practical constraints and decision-making priorities.
How impact will be measured
Bio-Phage UK is set up to generate evidence that is both scientifically robust and practically useful. Monitoring and analysis will include:
Direct greenhouse gas emissions monitoring at ground level to quantify changes in soil N₂O emissions linked to fertilised forage systems
Soil chemistry and nutrient dynamics to track changes relevant to nitrogen cycling and nutrient availability
Forage performance measures, including yield and other relevant agronomic indicators, supported by consistent field observations
Soil microbiome and functional analysis (metagenomics) to assess how treatments influence microbial communities and functional genes linked to nitrogen cycling
Full life cycle assessment (LCA) (aligned with ISO 14040/14044) to quantify impacts per hectare and per unit of output, and to support clear comparisons between treatments
Cost-effectiveness assessment, considering input costs, fertiliser savings and practical adoption implications
Integration of results into decision tools, including outputs formatted for tools such as the Cool Farm Tool, to support wider uptake and consistent reporting
Targets and expected outputs
The project is designed around measurable targets and clear outputs, including:
A target ~50% reduction in synthetic nitrogen use versus typical practice
A target reduction in soil N₂O emissions associated with fertilised soils (project target set at 12.5%)
Measurable improvements in soil organic carbon indicators over time, alongside wider soil health metrics
A clear, farm-relevant evidence base combining emissions, yield, soil function and economics
Planned outputs include practical project reporting for farmers and the wider sector, scientific insight into soil microbial function, and dissemination through a structured engagement programme (including on-farm events and wider knowledge exchange activity).
Alongside the farm-facing outputs, the programme aims to contribute to the scientific evidence base through peer-reviewed publication routes.
Want to keep up with results?
If you’d like updates as findings come in, or you’re interested in hosting trials or discussing nitrogen efficiency on your farm, please register your interest using our online contact form.
Interested in Hosting a Trial or Partnering with Us?
Whether you’re a research body, supply chain partner, or farmer exploring alternatives, we’d love to hear from you. Get in touch for a no-obligation chat.
Let’s build the next phase of on-farm innovation together.
The full Bio-Phage UK consortium met in person for the first time at the Citadel Environmental Solutions factory in Telford, bringing together the Terrafarmer team, BIOCAT developer Citadel, the University of Nottingham, and Fera Science. A good start to what promises to be an ambitious collaboration.
