Terrafarmer is leading a new, innovative Defra-funded project (delivered with Innovate UK) to test whether farms can replace around half of synthetic nitrogen fertiliser with biological alternatives, while maintaining performance and cutting emissions
You may have seen the public announcement about Defra’s £21.5m Farming Innovation Programme awards. We are delighted to announce that Bio-Phage UK is one of the funded Low Emissions Farming projects.
Background
After the last couple of seasons, most farmers already know that every unit of nitrogen has to work harder. Costs have been volatile, weather has been unpredictable, and the margin for error is tight. That’s especially true when you’re trying to hit the right application windows.
“We’re hoping to demonstrate a ~50% reduction in synthetic nitrogen use in the trial systems, with a measurable reduction in associated nitrous oxide emissions, while maintaining or improving performance.”
That’s the context for Bio-Phage UK. This innovative, Terrafarmer-led research and development project will explore how biological inputs and novel phage technology can help to reduce nitrous oxide (N₂O) emissions from UK farming systems by reducing reliance on synthetic nitrogen fertiliser while maintaining—and even enhancing—productive, resilient farming systems.

Why nitrous oxide matters
Nitrous oxide is a powerful greenhouse gas, 300 times more potent than CO₂. In farming systems, N₂O is closely linked to how nitrogen (N) behaves in soil after fertiliser applications. UK agriculture contributes 71% of national N₂O emissions, with dairy farms among the most intensive users of synthetic N.
The practical question is: can we improve nitrogen use efficiency and reduce losses to the atmosphere without sacrificing yield or grass growth?
What we’re testing
BIOCAT is a phage-based soil treatment designed to selectively suppress nitrifying bacteria and support beneficial microbial communities.
The Bio-Phage UK project will test a suite of biological inputs, including BIOCAT, thus combining biological inputs with this novel phage technology to tackle both the chemical and biological drivers of soil emissions.
The aim is to test whether targeted biological tools can help reduce emissions at source, while keeping crops and grass performing.
We’re hoping to demonstrate a ~50% reduction in synthetic nitrogen use in the trial systems, with a measurable reduction in associated nitrous oxide emissions, while maintaining or improving performance.
How the trials will work
The project is built around rigorous field trials on three commercial dairy farms across England, supported by glasshouse trials at the University of Nottingham.
Trials will assess 12 different treatments across ryegrass, herbal leys, and wholecrop systems (cereal harvested whole for fodder)—crops common to UK dairy farms. Alongside yield and agronomic performance, we’ll also measure:
- direct greenhouse gas emissions at ground level
- soil chemistry and nutrient dynamics
- microbial community changes (including DNA analysis)
- data suitable for lifecycle assessment (LCA)
The aim is to generate robust, scientific evidence that is practically useful for livestock and arable farmers across the UK.
Why this matters on farm
If it performs under real farm conditions, the on-farm opportunities are clear:
- lower emissions without a productivity hit
- better nitrogen efficiency (making more of what you apply)
- potential to reduce reliance on synthetic N in forage systems
- improved resilience through better soil function and nutrient cycling
- a clearer cost/evidence picture for what’s worth adopting (and what isn’t)
We will share updates as the work progresses, including what does and doesn’t work, with a focus on providing clear, practical advice to farmers on what it means for real farming decisions.
Project partners

Bio-Phage UK is being delivered by a consortium including:
- Terrafarmer Agriculture Ltd (field trials, agronomy, data integration)
- Citadel Environmental Solutions Ltd (BIOCAT developer)
- University of Nottingham (emissions measurement and lifecycle assessment)
- Fera Science Ltd (microbial and metagenomic analysis)
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.
You’ll find more detail and updates about Bio-Phage UK on our On-Farm Trials and Projects page.
Bio-Phage UK is funded by Defra’s Farming Innovation Programme, delivered in partnership with Innovate UK.


About the author
After gaining an HND in Agriculture, Tom Tolputt went on to work as an Area Manager and Farm Animal Nutritionist for Agri-King for seven years. Setting out his stall as an independent consultant, he began advising a range of organic and conventional farm businesses across the UK. He also runs the family farm, raising organic beef cattle and organic cereals at Lesquite Organics with his wife, Nic, near Looe in Cornwall.
About the author
After gaining an HND in Agriculture, Tom Tolputt went on to work as an Area Manager and Farm Animal Nutritionist for Agri-King for seven years. Setting out his stall as an independent consultant, he began advising a range of organic and conventional farm businesses across the UK. He also runs the family farm, raising organic beef cattle and organic cereals at Lesquite Organics with his wife, Nic, near Looe in Cornwall.
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