Yr15-virulence in Yellow Rust Confirmed in Continental Europe
Significant implications for disease resistance in European wheat cultivars
Yellow rust Yr15-virulence confirmed in continental Europe
The Global Rust Reference Center (GRRC, Aarhus University) has confirmed Yr15-virulence from multiple cultivars and sites in continental Europe based on field observations and laboratory assessments of samples submitted by European collaborators, and Danish extension organisations led by SEGES Innovation. This follows similar observations in Northern England during April and May, where wheat cultivars carrying Yr15 resistance became infected with yellow rust according to a report last month by NIAB, UK.
The Yr15 resistance gene, introduced into European wheat breeding in the late 1990s, is widely deployed across modern cultivars. The detection of virulence against this gene in multiple European regions raises concerns about the future effectiveness of this resistance in commercial wheat production.
“While current outbreaks may have limited impact due to late arrival this season, we anticipate greater challenges in future years -especially if mild winters and humid, cool nights in spring persist,” said Professor Mogens Støvring Hovmøller, leader of the GRRC and coordinator of wheat rust activities within the Horizon Europe-funded project IPMorama.
Until now, Yr15-virulence had been an exceptionally rare occurrence. Among thousands of yellow rust samples submitted to the GRRC from over 50 countries across six continents, only a single historical case (2002) had previously shown this virulence.
Figure 2. Wheat seedlings carrying Yr15 used for virulence testing in GRRC lab
Sentinel Plot Network in Action
The IPMorama project has deployed “sentinel plots” across Europe to help monitoring the emergence and spread of new yellow rust races. One such cultivar, Mariboss, known to carry Yr15, was included in more than 80 trial sites during autumn 2024 in collaboration with the European Value for Sustainable Cultivation and Use (VSCU) trial network.
Initial alerts from the IPMorama rust monitoring system suggest that northern France and Belgium may be emerging as hotspots for yellow rust infections on Yr15 cultivars, but final conclusions must await further observations.
“This long-term partnership with European VSCU trial networks, under the coordination of Valérie Cadot from GEVES (France), gives us an invaluable early-warning system,” said Hovmøller. “Our next steps include rust sample collection, genotyping to compare with known global rust races, and assessing their epidemic potential on breeding lines and currently deployed cultivars.”
Link to results from the VSCU network here
Coordinated Response Required
“This development underlines the importance of international surveillance and data-sharing,” said Dr Dan Milbourne, IPMorama coordinator. “We must integrate virulence tracking with varietal deployment strategies to ensure that breeders and growers alike can respond swiftly and effectively.”
Moving forward, close monitoring of pathogen evolution, strategic resistance breeding, and coordination across national and European crop protection networks will be vital to mitigating the threat of future rust epidemics.
Contact Information
Global Rust Reference Center (GRRC)
Aarhus University, Denmark
Prof. Mogens Hovmøller
E-mail: mogens.hovmoller@agro.au.dk
IPMorama Project
Integrating Breeding for IPM into the Deployment Landscape for Wheat, Potatoes, and Grain Legumes
Website: www.ipmorama.eu
Coordinator: Dr Dan Milbourne
E-mail: Dan.Milbourne@teagasc.ie
European VSCU Expert Group
Website: https://www.geves.fr/news-en/eu-vcu-group-annual-meeting/.
Head of VCUS bioagressor resistance testing: Valerié Cadot
E-mail: valerie.cadot@geves.fr.