How a vast data set guides variety recommendations

In the final blog of the winter wheat on trial series, Paul Gosling, who manages the Recommended Lists for cereals and oilseeds (RL), explains how a large variety performance data set underpins recommendation decisions.

Since autumn 2024, the RL winter wheat on trial initiative has told the story of the whole variety-recommendation process – from deciding which varieties to grow in trials to updating the lists each year.

As we gear up to release the next RL edition online on 1 December 2025, it's time to consider how trial data drives recommendation decisions.

The initiative has mainly looked through the lens of a fungicide-treated winter wheat trial site in Norfolk (Terrington St Clement), which was harvested in early August and the subject of my previous blog.

The site’s yield results were added to a much broader data set, which also includes:

• Results from all 31 dedicated UK winter wheat fungicide-treated harvest 2025 yield trials
• Information on many other variety performance characteristics
• Results from previous RL trial harvest years
• Data from the statutory GB and NI Variety Lists (VL) trials

In total, the data set covers results from over 80 yield trials for candidate varieties and more than 300 trials for long-established control varieties. 

The RL Board delegates technical decision-making to its three supporting crop committees.

Chaired by agronomists or farmers, these committees collectively represent the whole supply chain.

The RL wheat crop committee first used the initial trial data in September to decide which varieties to drill this autumn, with the harvest 2026 sowing lists already available to download.

Since then, the AHDB RL data team has pulled together even more data, including information on quality characteristics, derived from milling, baking and distilling tests on grain samples from the harvest 2025 trials.

The wheat crop committee is now using the expanded data set to decide which varieties should make it on to the new winter wheat list (and which should be removed).

The committee follows a well-defined process that accounts for fungicide treated and fungicide-untreated yields, disease resistance, agronomic traits, grain quality and end use characteristics.

During this process, data is weighted to ensure that the most important characteristics have a bigger impact on the outcome.

Over the last 15 years, we have seen a gradual shift in priorities. For example, the weightings for fungicide-untreated yield and disease resistance characteristics have increased recently (in response to farmer-demand for more resilient varieties).

If candidate varieties perform well, relative to varieties already on the list, there is a good chance that they will provide a consistent economic benefit to industry and secure recommendation.

To facilitate comparisons, varieties on the list are used to set a fungicide-treated yield target.

Varieties with strong agronomics and grain quality are also identified (comparator varieties) to test the relative performance of candidate varieties.

A high-yielding candidate variety may still fail to secure recommendation, if it is deemed to have a substantial weakness compared to comparator varieties.

Conversely, varieties below the fungicide-treated yield target can still make the grade, if they have a particular strength lacking in the comparators.

For their final recommendation judgement, the committee considers the overall balance of features, to be sure that a variety’s advantages always outweigh any disadvantages.

If a variety meets the well-established criteria and required standards, it will be proposed for recommendation.

Of course, this means there is no limit on the number of new varieties that can be added to a list.

However, of the nearly 700 farmers who responded the most recent RL review, most (over 75%) thought the numbers on the RL were ‘about right’.

The two other crop committees, which cover oilseeds, and barley, oats and other cereals, follow a similar process (although malting quality is particularly important for spring barley recommendations).

The RL Board reviews and ratifies the crop committees’ decisions, which includes consideration of any appeals from plant breeders, so that all final recommendation decisions are fair.

As soon as the decisions are finalised, the RL data team works tirelessly to prepare for launch.

This includes the meticulous creation and checking of all RL data tables for release in the online tables, followed closely in the new year by the RL booklet, RL app, RL variety selection tools and RL interactive.

The final step is to review the whole process with the in-house RL team, the RL Board and crop committees, contractors (including trial operators) and stakeholders (including BSPB).

Any improvements identified are implemented to refine the variety-selection process and ensure that the lists continue to provide levy payers with the best information possible to make their variety choices.

Members of the farming press are invited to attend the online RL 2026/27 media launch on the morning of 1 December 2025, which includes an in-depth analysis of the key developments (presented by members of the RL team).

Members of the farming press can register their interest by emailing jason.pole@ahdb.org.uk

We're recruiting a new RL Board Chair, following the retirement of the current Chair at the end of 2026. As Chair Designate, the appointee will shadow the current Chair in 2026 before taking over as Chair in 2027.

Application deadline: 14 November 2025.