Important to keep things in perspective
Yellow rust is a highly dynamic pathogen that is constantly changing and developing new strains, all of which are potentially capable of affecting plants to lesser or greater degrees.
It is now clear that a new strain of yellow rust has emerged this year that is capable of developing symptoms in plants despite the presence of the long established YR15 gene found in many popular RL varieties currently, including some of the highest yielders on the list.
This is not a failure of genetics or a 'breakdown' of resistance, but simply the result of an ongoing natural process that has driven the evolution of all living organisms since time began. It has happened before in cereal diseases and will happen again.
While this is an unwelcome development, we urge growers and their advisors to keep the YR15 issue in perspective and not make hasty decisions that could affect the resilience and overall production of their wheat enterprises in the future.
Forewarned is forearmed. Fungicides are particularly effective against yellow rust and relatively low cost with many agronomists saying a suitable application at T0, costing in the region of £5/ha, is likely to stem any development of the disease.
In last year's AHDB harvest results, DSV Champion was consistently the highest yielding winter wheat across most locations in the UK. Its RL yield of 107% of control gives it a yield advantage some 4% above the average for all Group 4 varieties on the current RL.
At a control yield of 10.8t/ha, this is the equivalent of 0.43t/ha over average group 4 performance which, at a current forward price for wheat of c. £180, is worth over £77/ha - many times more than the cost off using a cost-effective fungicide to control yellow rust at T0.
This is before you add in other standout features of DSV Champion including the highest resistance score to septoria at 7.6 of all hard Group 4 winter wheats on the RL, arguably a much more serious threat to wheat in the UK than yellow rust.
DSV Champion also scores 108% of controls in the early drilling slot and 106% in the later one plus it has a latest safe sowing date of mid-February, giving growers excellent rotational flexibility in increasingly variable weather conditions.
The variety's resilience in the field, across many different growing conditions and in a range of production systems from high input to regenerative, has been proven over many years.
It would be a false economy for growers who have enjoyed the considerable benefits of DSV Champion in the past to select a lesser performing variety, many of which have needed more intensive agronomic programmes to keep disease under control anyway, simply because of the YR15 issue.
We would therefore urge all growers to rationalise the true risk of the YR15 issue with their agronomist and not delay ordering the seed they want as they could find themselves unable to get DSV Champion and have to take a poorer performing variety by default.
For further information, please contact Sarah Hawthorne or Dr. Matt Kerton at DSV UK