Act early to prevent yellow rust from taking hold
Growers could face yield losses of up to 30 per cent if they do not stay vigilant against yellow rust this spring.
Yellow rust, which affects the photosynthetic ability of crops primarily by reducing leaf area, can become particularly prevalent in warm and damp conditions similar to those that are currently being seen across the country.
Disease spores need daytime temperatures to reach 10°C to 12°C to develop. Combine these temperatures with rainfall, and you’ve got the perfect storm for the disease.
It’s also worth remembering that we haven’t had a harsh winter. It’s thought that yellow rust pressure can be reduced if between six to ten hard frosts, where temperatures drop below five degrees, happen over the winter. But as we didn’t experience this, yellow rust spores have had little trouble staying viable over the winter.
These conditions mean growers need to keep an eye out for signs of yellow rust and act early to prevent it from impacting crop development, and ultimately yields.
We’re already seeing yellow rust appearing in many popular wheat varieties including Gleam, Skyscraper, Firefly and Skyfall. Late planted crops tend to be much more susceptible to disease, but it can affect any wheat crop, particularly those grown in the east of the country.
If you’ve got a yellow rust issue, it’s likely you’ll see small pustular yellow spores on the green plant tissues in the early stages of crop growth. As an infection develops, and without any control to nip it in the bud, the disease can develop into more obvious lines of pustular yellow growth.
To tackle the early stages of the disease, I’d recommend a robust fungicide programme incorporating a strobilurin or triazole based product at T0. This will help tackle the disease early and prevent the infection from becoming a bigger problem.
However, if yellow rust continues to be a problem later on in the season, applying an SDHI product, such as Wolverine, at T1 will give you the best chance of gaining control and reduce the risk of significant yield loss.
Being vigilant against this disease is vital as it can crop up quickly and unexpectedly.
Jeff Fieldsend is FMC commercial technical manager
