Urease Inhibitor

NitroShield is OMEX's innovative new urease inhibitor to reduce ammonia emissions and farm more sustainably. Defra has announced new rules on ammonia mitigation for urea fertilisers which includes UAN liquid fertilisers, such as Nitroflo. Including NitroShield in liquid nitrogen fertiliser applications will help farmers meet legislation whilst improving efficiency, and ensure they're using the most effective application rates. NitroShield has undergone 3 years of rigorous testing to establish the most efficient and effective form of urease inhibitor available to farmers.

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NitroShield Webinar

Watch our on-demand webinar for everything you need to know about reducing ammonia emissions and farming sustainably with OMEX's NitroShield


70% reduction
in emissions

The NitroShield urease inhibitor has repeatedly demonstrated over 70% reductions in ammonia emissions from urea containing fertilisers



With less ammonia lost to the atmosphere, and contained within the soil, the nitrogen applied alongside the NitroShield urease inhibitor is better utilised by the crop


Meets Industry

NitroShield meets the government target of reducing ammonia emissions by 70%, helping farmers grow more sustainably

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    Making the move to Reducing Ammonia Emissions on farm

    Government guidence on Urea containing fertilisers:

    Defra has announced new rules on ammonia mitigation for urea fertilisers which includes UAN liquid fertilisers, such as Nitroflo. From 2024 farmers must inhibit their urea containing fertiliser application, excluding foliar applied urea, from 31st March each year. Further information can be found on the government website, here.

    How farmers can reduce emissions from Urea containing fertilisers:

    • Defra are looking to reduce ammonia emissions by 70%, choose an inhibitor such as NitroShield that has been trialled to meet these standards. Take a look at our demonstrations below.
    • Plan your fertiliser application wisely, you can use DIDIN if you chose to apply your full dose of liquid nitrogen fertiliser before 31st march, to prevent nitrate leaching and to improve NUE.
    • Use the correct application rate. NitroShield can be used at a reduced or a full application rate to suit the farms requirements and to ensure you're applying the optimum rate, improving nutrient use efficiency.

    How will the scheme be managed?

    The government guidelines will be checked upon by the Red Tractor Farm Assurance Standard. Your local OMEX FACTS qualified advisor will be able to advise you on best practice for urea containing liquid fertilisers.

    How NitroShield works to reduce ammonia emissions

    NitroShield is a urease inhibitor that works by blocking the urease enzyme from hydrolysing urea which causes ammonia losses, helping farmers to reduce emissions and farm more sustainably. NitroShield has been specifically developed, and rigorously tested, to meet government guidelines on reducing ammonia emissions from 2024, in line with the Red Tractor Farm Assurance Standard. Throughout the trials process the OMEX R&D team have worked to establish the most efficient rate farmers should use, to make sure they're fully utilising their inputs and nothing is going to waste

    David Booty
    Technical Development Manager
    OMEX Expert David Booty

    Research and Development of NitroShield

    NitroShield has undergone three years of rigorous testing. During these trials we've not only looked at how effectively NitroShield reduces emissions, but what the most efficient rate to use is. Alongside our field trials we've been continuously testing the product in the lab, capturing gas emissions which meet international standards with NitroShield consistently reducing ammonia losses by more than 70%.
    We've also seen small yield increases when using the OMEX inhibitor, alongside NIAB trials showing a 0.3 t/ha increase in yield.

    OMEX network grid graphic

    "Other inhibitors are available" but...

    This trial demonstrated how effectively emissions were reduced when using NitroShield compared to a competitor product. The axis on the left represents ammonia emissions in ppm.

    NIAB Trials: UK 2016 & 2017

    This trial demonstrated the improvement in yield when using the NitroShield urease inhibitor alongside the application of UAN liquid fertiliser, demonstrating an improvement in nitrogen use efficiency (NUE).

    Farmer benefits?

    Grain yield in wheat trials from 30N + NitroShield v. 30N alone:

  • 2016, NIABTAG Morley, UK +400 kg/ha
  • 2017, NIABTAG Morley, UK +300 kg/ha
  • Mean of trials in UK, CZ, PL +330 kg/ha
  • 10 trials in France 2014-15 +0.2% Protein
  • Higher grain yield and protein = improved Nitrogen Use Efficiency

    Reducing Ammonia Emissions

    Reducing ammonia emissions not only meets Red Tractor Farm Assurance standards, but it also helps improve Nitrogen Use Efficiency on farm. Using a urease inhibitor such as NitroShield will help protect the environment, reduce emissions and improve yields for farmers throughout the UK.

    Speak to your FACTS qualified advisor about your liquid fertiliser application.

    OMEX are here to help you navigate your way through the new guidance implemented by Defra. The OMEX team of advisors are FACTS qualified and able to guide on how best to apply your liquid fertiliser to suit both your operation and guidance from the government. OMEX operate throughout the UK with a robust research and development department, dedicated to working with farmers to improve agricultural sustainability and get the most out of your fertiliser applied.