Tillage farmers on alert for yellow rust in spring 2026
Teagasc is indicating that over 90% of winter wheat crops could be susceptible to yellow rust during the early spring months.
This is particularly the case if weather conditions are suited to the spread of the fungus.
The source of the threat can be traced back to the breakdown of a yellow rust resistance gene in winter wheat crops growing in the north of England last year (2025).
The fungus thrives in dry, warm conditions. Sources of infection include spores that have been lying in dormant in the trash from infected crops grown the previous year and green bridges.
Yellow rust
Most tillage areas in Ireland saw outbreaks of yellow rust impacting on winter wheat crops in 2025.
Teagasc tillage specialist, Shay Phelan, addressed the issue at a Teagasc Spring Tillage seminar held in Dundalk earlier this week.
He said: “We know that approximately 75% of the winter wheat varieties now available are susceptible to yellow rust attack.
“Addressing the issue required growers taking two courses of action.
"Firstly, they should check their crops for early signs of the disease getting a foothold in the early spring period
“This should be accompanied by the application of a T0, Leaf Four, proprietary fungicide that can deliver high levels of yellow rust control.”
The Teagasc representative referenced an azole that can be applied in combination with a complimentary product.
“Beyond T0, an additional three spray programme can be implemented with a strong focus on septoria control: Leaf Three, Flag Leaf and then finishing off with a head spray," Phelan continued.
“It’s important that all fungicides are used in ways that recue the threat of disease resistance.
"The reality is that it could be a number of years before new fungicide chemistries will be available."
Cereal crops
Meanwhile, most cereal crops that were established in ground not prone to flooding last autumn have wintered well.
Phelan said: “The one downside to the extremely wet conditions since the turn of the year has been growers’ inability to get weed control measures implemented in their winter cereals.
“Where winter barley is concerned, we are past the point of no return in getting full control over annual meadow grass.
“Minimising the extent of the problem is the best that can be hoped for at this stage.
"With winter wheat, however, there is still a window to get a strong grip on grassland weed-related issues."
The Teagasc representative noted that, given the persistent rain of recent weeks, barley crops "may have started to yellow in some areas".
“Getting early nitrogen applied in such instances will be a priority, once weather and ground conditions improve," he added.
