Winter oats recommended list

Recommended List winter oat harvest results show good fungicide-treated yields, but high levels of disease devastating yield in some fungicide-untreated trials

The harvest results for the majority of RL winter oat trials are now available, with just two sites still to report. Eight fungicide-treated trials have reported: Devon, Kent, Hampshire, Cambridgeshire, Lincolnshire, Herefordshire, Yorkshire and Fife. Results from fungicide-untreated trials are also available at all the same locations except the Hampshire site.

The average yield of control varieties in the treated trials stands at 9.10 t/ha, a little ahead of the five-year average (8.94 t/ha). However, some of the fungicide-untreated trials were severely impacted by crown rust, as a result the yield of the control varieties is just 5.33 t/ha that’s 1.84 t/ha below the five-year average (7.17 t/ha).

2023/2024 season

Though difficult for many commercial crops and trials, this season proved to be relatively trouble-free for RL winter oat trials. Trials were drilled before the weather broke in the autumn and established well. The mild and wet winter and spring meant however, that conditions were perfect for disease. Levels of crown rust in some fungicide-untreated trials were more than 30% in susceptible varieties, with more than 60% seen in one trial in Essex. Some varieties even failed to come properly into head so severe was the infection. Rain and strong winds also resulted in widespread lodging, even where PGRs had been applied.

Calculating yield results

Yields are represented as a percentage of the control varieties. In 2024, Dalguise, Mascani and Cromwell are the control varieties. The average yield from these varieties is represented as 100%.

2024 results

In the fungicide-treated trials the husked variety RGT Southwark is highest yielding so far (108%) with Dalguise (105%) and Cromwell (103%) a little behind. Market leader Mascani has not had a good 2024 and lags someway behind on 92%. The year 4 candidate variety Valentine has also struggled in 2024 and is on 97%. It will be considered for recommendation in November.

Three year 3 husked candidates are also in trial this year, but they won’t be considered for recommendation until autumn 2025. They are KWS Pertinent, RGT Dempsey and Rannoch. RGT Dempsey has performed well on fungicide treated yield in 2024 (109%), Rannoch is a little way behind on 104%, with KWS Pertinent well behind on 94%.

For the naked varieties, the market is different and yield isn’t everything. The naked varieties had not performed well in the early results in 2024 but have recovered now more data is in, with Peloton (76%) and Fusion (72%) just 1% below their five-year average, with Grafton matching its five-year average (71%).  The year 3 naked candidate Avalon is the highest yielding naked variety in the fungicide-treated trials on 80%, but won’t be considered for recommendation until autumn 2025.

The fungicide-untreated trials have thrown up some astonishing results as a result of the high levels of crown rust that came into some trials very early. In the Devon trial, which was low yielding, Fusion, with a crown rust rating of 3, has yielded just 2% of controls (40 kg/ha), and done only a little better in the Kent trial (14% and 0.39 t/ha).  In these same trials RGT Southwark, with a crown rust rating of 7, has yielded 241% of controls (6.66 t/ha) in the Kent trial and 134% (2.98 t/ha) in the low yielding Devon trial.

Overall the fungicide-untreated trials Dalguise with a crown rust rating of 4 has suffered, yielding just 87% of controls, less than Mascani (99%) and even the naked variety Peloton (99%) which has a crown rust rating of 6. RGT Southwark is highest yielding (138%), well ahead of any other recommended variety, with Cromwell (rated 5 for crown rust) second highest on 115%. Two of the year 3 candidates RGT Dempsey (137%) and Rannoch (149%) have also yielded very well, suggesting good resistance to crown rust, though they won’t be eligible for recommendation until autumn 2025.

Five-year averages

The 2024 results show yields based on one season. The five-year average is a better measure of variety performance over seasons.

On this measure all the recommended varieties align with their current RL yields. RGT Southwark is highest yielding in the fungicide-treated trials (107%), followed by Cromwell and Dalguise (103%). The year 4 candidate variety Valentine is on 100%, with Mascani is as expected well behind on 95%.

In the naked varieties, Peloton is the highest yielding (77%), followed by Fusion (73%) and Grafton (71%).

In the fungicide-untreated trials even in the five-year average, the impact of the significant crown rust epidemic of 2024 can be seen. RGT Southwark is highest yielding (115%), with Cromwell on 106% and candidate variety Valentine on 103%, with year 3 candidate Rannoch (120%) and RGT Dempsey (115%) performing well. In the naked varieties, Peloton is again the highest yielding (86%), followed by Grafton (74%) and Fusion (66%), with year 3 candidate Avalon on 78%.