Wednesday 30th September 2026

We begin on Wednesday with presentations of interest to all delegates; after lunch, with opportunity to view poster, we will split to parallel stream for those interested in crop nutrition, and those interested in fertiliser production. 

JOINT OPENING SESSION – LECTURE THEATRE

Welcome and opening address from IFS president, Hans Reuvers

Building climate-resilient agriculture in Europe: an economic perspective

Bengü Seriflogu, European Environment Agency, Copenhagen, Denmark

Summary to follow

AGRONOMIC PRESENTATIONS

What is the influence of mineral fertilisation on C storage in agricultural soils?

Lionel Jordan-Meille, Bordeaux Science Agro, Bordeaux, France

In agricultural soils, the total amount of stored carbon (C) constantly fluctuates based on inputs (crop residues, roots biomass and exudates) and outputs (mineralisation driven by microbial activity). The study aims to understand how mineral fertiliser inputs (N, P) influences these fluxes and in which direction they are eventually driven.

Two hypotheses with opposing effects were formulated : i) a positive impact from mineral inputs resulting from improved yields, and, conversely, ii) a loss of stored carbon resulting from the activation of mineralisation processes that deplete the soil’s stable carbon pool—similar to the effects observed with liming.

The study is based on an extensive literature review incorporating numerous results from long-term fertiliser trials conducted both in France and internationally. The study also compared the effect of mineral fertiliser use with other cultivation techniques known to enhance C storage, such as introducing cover crops, agroforestry, reduced tillage and application of organic materials (manures etc). The study ends with a global C mass balance, including the losses associated with fertiliser production.

It’s up to you to guess if fertilisation has a global positive or negative effect. Hear the answer in Warwick!

Agronomic benefits of microbial and non-microbial biostimulants: A meta-analysis of Europe-wide field trial programs

Narges Moradtalab, Yara Hanninghof, Germany

Microbial and non-microbial biostimulants are increasingly used, with claims to improve nutrient-use efficiency, nutrient acquisition, crop performance, stress resilience, and yield stability. Evidence from European-funded research programs from 2012 to 2025 shows that biostimulants can support more efficient use of mineral and organic nutrient inputs by enhancing root activity, improving nutrient uptake, and strengthening plant performance under abiotic stress. From a plant nutrition perspective, their value addition does not only depend on their biological mode of action, but also on how they are formulated and integrated into fertilization programs, considering crops and agro-ecological conditions.

This review combines field-scale agronomic meta-analyses, mode-of-action studies under controlled conditions, as well as scientific trials carried out by Yara’s agronomic R&D teams across selected biostimulant categories. The BIOFECTOR research program, an EU-funded initiative conducted from 2012 to 2017, evaluated microbial and non-microbial biostimulants, referred to as bio-effectors. The meta-analysis included 107 bio-effector treatments across 94 controlled pot experiments and 47 field experiments in maize, wheat, and tomato. Across 945 observations, bio-effectors increased crop growth and yield by an average of +9.3%. Follow-up research activities in Horizon 2020 from 2017 to 2025 added field-relevant mode-of-action evidence, showing that performance is linked to, e.g., rhizosphere competence, root growth, fertilisation history, tillage practice, and method of product application, such as seed treatment, foliar, or soil placement. Yara’s product and agronomic R&D program further looked into the integration of biostimulants into fertiliser management. Over 678 field trials carried out from 2018-2024 across tested non-microbial biostimulant products, the trials showed an average yield increase of +6.8% over the untreated control (without biostimulants).

The evaluated type of product portfolio included active categories such as seaweed extract, humic substances, silicon plus choline, vitamins, and plant-derived actives. The results are consistent with global benchmark meta-analyses on microbial and non-microbial biostimulants. Li et al. 2022 reported an average +17.9% yield benefit across 1,087 paired open-field observations from 180 studies, while Herrmann et al. 2022 reported positive effects on plant growth, yield, crop quality, and plant nitrogen and phosphate contents across 1,791 observations from 186 studies.

Biostimulants can contribute positively to sustainable crop production. Their strongest value is achieved when the right product and formulation are matched with the right crop, soil, fertiliser strategy, stress scenario, and application timing. Therefore, the key question is not only whether biostimulants increase yield, but when they improve nutrient-use efficiency, where they support nutrient uptake and stress resilience most effectively, and which formulation and delivery system enables reproducible field performance. The right combination of biostimulants with plant nutrition can contribute to a more efficient, resilient, and sustainable fertiliser use in integrated plant nutrition systems.

Potential benefits of variable rate nitrogen applications for winter wheat, barley and oilseed rape

Kate Storer, ADAS, UK

Large claims are made for VRN technologies to improve yields while reducing environmental impacts of cropping, and several studies have demonstrated large variation in both yields and crop nitrogen requirement within fields.

This study will report on analyses from 11 large scale (3-5ha) field trials in winter wheat, winter barley and oilseed rape to understand the potential benefits of VRN. Modest benefits of VRN for yield, gross margin and greenhouse gas emissions were found, above applying a uniform rate at the average optimum N rate. Growers are encouraged to prioritise estimating the field average fertiliser N requirement as accurately as possible as this provides almost the same benefits as a VRN application

Crop Modeling to Support on Farm N management – applications in Eastern England

David Clarke, Niab, UK

Through a NERC PhD, TMAF-supported research, and more recently Innovate UK funding with Catalyst Farming, we have been developing and demonstrating the use of crop simulation models to support nitrogen (N) management in wheat. By parameterising models at the sub-field scale, local soil, climate and seasonal interactions can be simulated to inform site-specific N management strategies and wider on-farm decision-making. This presentation will also explore the future potential of these approaches to support hyper-local assessments of climate change impacts, adaptation and mitigation, helping farmers make more resilient and sustainable management decisions.

TECHNICAL PRESENTATIONS

The Behavior of ammonium nitrate in Organo-mineral Fertilisers

Wolfram Franke, Yara Porsgrunn, Norway

The 2019 European Union Fertilising Products Regulation expanded the scope of fertilisers compared to the previous 2003 regulation. Included among the new product function categories are organo-mineral fertilisers (OMFs). OMFs are organic fertilisers enriched with mineral nutrients to enhance their fertilising potential, and ammonium nitrate (AN) is one of the permitted mineral nitrogen (N) inputs.

Agronomic testing of AN-based prototype OMFs in greenhouse trials indicated performance at par with mineral N fertilisers, prompting investigations into product safety, both, during production and storage, since organic matter (OM) and AN are known to be chemically incompatible. This is because OM can trigger reactions with the nitrate fraction of AN, ultimately driving the decomposition of AN and leading to a combustion reaction. Today’s regulatory framework covers formulations with an AN content of more than 45%, and limits organic matter as a contaminant. However, what about mixtures with less than 45% AN, and where OM is supposed to be a major input?

The study presented here seeks to map the compatibility boundaries of OMs with AN, by differing their concentrations to evaluate how these combinations can influence the products’ thermal stability. We conclude with the suggestion for a working window for formulations, with suggested guideline limits on AN inclusion.

Urea Co-crystals – advanced plant nutrition and beyond

Andy Kells, AKG Engineer Consulting Ltd, Belfast, Northern Ireland, UK

Developing from Proceeding 902 in 2025, this presentation will look in more detail at how urea-gypsum co-crystal are created, both chemically and physically, and examine how the method of production and therefore structure affects the granulation process. The presentation will also consider which forms of gypsum are suitable, with particular reference to utilising phosphogypsum. The likely onward use and potential additional manufacturing benefits, such as micronutrient addition, will also be considered.

Cadmium Leaching Process: An Innovative Technology to Remove Cadmium from Phosphate Rock

Julien Rappazzo , Prayon, Belguim

This presentation will introduce an innovative process developed by Prayon to selectively remove cadmium from phosphate rock. The key stages of the technology development, the underlying process principles, and the performance achieved to date will be outlined.

This technology was developed in response to new regulations regarding cadmium presence in fertilisers, which has become a challenge for our industry .

The process is based on the acidic leaching of phosphate rock in the presence of a specific anion, which promotes the selective dissolution of cadmium.

Under optimised operating conditions, the technology enables the removal of the majority of the cadmium contained in the phosphate rock. In addition, Prayon has developed complementary process steps that allow the  recovery of nearly all the phosphate content contained in the ore and therefore an overall P₂O₅ yield close to 100%.

This technology is particularly relevant for fertiliser production, where phosphate rock is used directly as one of the primary raw materials.

Today, fertiliser producers must often rely on either :

• The availability of naturally low-cadmium phosphate rock deposits, which are limited and unevenly distributed; and/or
• Costly phosphoric acid decadmisation technologies

By removing cadmium directly from the phosphate rock before acidulation, Prayon’s process provides a cost-effective and scalable solution for producing low-cadmium fertilisers. It expands the range of phosphate resources that can be used while helping producers comply with current and future regulatory requirements.

A New Route to Sulphate of Potash Production Using Gypsum and Captured CO₂

Nicolas White, Vateris, Nottingham, UK

Sulphate of potash (SOP) is an essential chloride-free potassium fertiliser for high-value crops, yet existing production routes face increasing challenges related to energy consumption, carbon emissions, sulphuric acid supply and by-product management. This paper reviews the principal industrial methods currently used for SOP manufacture and examines the factors driving interest in alternative production technologies. A new production route based on gypsum, potassium hydroxide and captured carbon dioxide is presented, with a particular focus on process chemistry, carbon mineralisation and the utilization of gypsum, including the potential use of phosphogypsum. Pilot-scale results are discussed, demonstrating the production of high-purity SOP alongside a valuable calcium carbonate co-product for use in the construction sector. The presentation considers the technical, environmental, and resource-efficiency benefits of this approach and its potential contribution to a more sustainable and resilient European SOP supply chain.