Yield of control varieties in fungicide-treated trials is 6.80 t/ha, which his 0.86 t/ha below the 5-year average
Yield of control varieties in fungicide-untreated trials is 6.25 t/ha, which his 0.72 t/ha below the 5-year average, despite low disease levels
Specific weight and Kernel content are down, and sieving’s up compared with 2024

Results for eight fungicide-treated spring oat RL trials and seven fungicide-untreated trials are now available. The average yield of control varieties in the fungicide-treated trials is 6.80 t/ha, which is 0.86 t/ha below the five-year average of 7.66 t/ha. Yield of control varieties in fungicide-untreated trials is 6.25 t/ha, which his 0.72 t/ha below the 5-year average of 6.97 t/ha, despite low disease levels. This is despite lower levels of mildew and very little crown rust been seen in trials in 2025.

Calculating yield results

Yields are represented as a percentage of the control varieties. In 2025 Canyon, WPB Isabel and Merlin are the control varieties. The average yield from these varieties is represented as 100%.

2025 results

Like many commercial spring crops RL trials have suffered from the drought and heat this spring and summer. Despite this, the only trials lost were in Northern Ireland, due to storm damage. However, yields were reduced in most locations compared with 2024, with particularly low yields in Hampshire and Lincolnshire. Though some trials further north yielded similar to 2024, stopping the overall average declining too much.

With a relatively small number of oat trials and high LSDs care should be taken not to overinterpret the results from one year. Good performance in 2025 is not necessarily a sign of drought tolerance nor vice versa. Having said this, highest yielding of all varieties in fungicide-treated trials in 2025 is newly recommended Caledon (105%) followed very closely by Merlin (104%) and Asterion (103%), Merlin and Asterion both well above their five-year averages. Some way behind these are WPB Isabel (99%) and Canyon (97%) with Conway (93%) and RGT Vaughan (92%) further back still.

The naked varieties Oliver (73%), Lennon (71%) and Ovation (69%) have yielded relatively well, equal to or above their five-year averages in 2025.

In fungicide-untreated trials newly recommended Caledon (109%) again tops the table, with Asterion just behind on 108%, well above its five-year average. Merlin (104%) and Canyon (102%) are somewhat lower yielding, with WPB Isabel (94%), Conway (93%) and RGT Vaughan (91%) again further back still.

The naked varieties Ovation (71%) and Lennon (69%) have yielded equal to or above their five-year averages in fungicide-untreated trials in 2025, while Oliver (62%), with a resistance rating of only 3 does seem to have suffered from the mildew where it was present.

Five-year average

The five-year average yield is a better measure of variety performance over seasons, especially with smaller datasets like spring oats.

On this measure, newly recommended Caledon is highest yielding in the fungicide-treated trials (104%) someway ahead of Merlin (101%) and WPB Isabel (100%). Asterion and Canyon are on 99%, with Conway on 95% and RGT Vaughan on 93%. Oliver (71%) is highest yielding of the naked varieties, with Ovation and Lennon on 69%.

In the fungicide-untreated trials newly recommended Caledon is highest yielding (107%), with Merlin on 103% and Asterion and Canyon on 102%. Ovation (70%) is highest yielding of the naked varieties, with Lennon just behind (69%).

Candidate varieties

Oat varieties have two years in trial as RL candidates before being considered for addition to the Recommended List. The five-year average yield is a better measure of variety performance over seasons, especially for candidates.

Four varieties this year are in their second year as RL candidate and so will be considered for recommendation in a few weeks time. Highest yielding of these in the fungicide-treated trials is Jacky (102%), followed by Neptun (101%) KWS Vibrant (100%) and Nova (98%). Clyde is in its first year as and RL candidate so won’t be considered for recommendation until 2026. It is currently on 100%.

In the fungicide-untreated trials Jacky is highest yielding on the five-year average (105%) followed by Neptun and Nova on 103% and KWS Vibrant on 101%. Clyde is on 99%.

With oats grain quality is key. Clyde and Neptun have high specific weight and kernel content, though sieving’s are a little higher for Clyde. Jacky appears to have a little lower specific weight, though kernel content and sieving’s are better. KWS Vibrant and Nova have high sieving’s, though kernel content and specific weight are acceptable. What is noticeable in these results is that grain quality for spring oats is much better at the Scottish sights and this is something that is seen in most years.

Further information

Access full trial results via the AHDB website: ahdb.org.uk/harvestresults

AHDB Recommended Lists (RL) trials test variety performance under optimum conditions. Care should be taken when making comparisons with commercial yields. Results from individual trial sites should not be used to make conclusions on variety performance. The RL publications are based on information from trials across the UK over several seasons. As more information becomes available from the current harvest, this will contribute to the over-trials averages – which comprise four years for oilseeds and five years for cereals. These averages provide better information for comparison between varieties. Performance variation is not the responsibility of AHDB. Since the focus is to test new varieties, not all RL varieties are presented. Yields for well-established varieties are published at ahdb.org.uk/rl