Laura Morales ^1,2* Deniz Akdemir ³ Anne-Laure Girard ² Anton Neumayer ⁴ Vinay K. Reddy Nannuru ⁵ Fahimeh Shahinnia ^6,7 Melanie Stadlmeier ⁴ Lorenz Hartl ⁶ Josef Holzapfel ⁸ Julio Isidro Sánchez ⁹ Hubert Kempf ⁸ Morten Lillemo ⁵ Franziska Löschenberger ¹⁰ Sebastian Michel ¹¹ Hermann Buerstmayr ²

• ¹ Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
• ² Institute of Biotechnology in Plant Production, Department of Agrobiotechnology, University of Natural Resources and Life Sciences Vienna, Tulln an der Donau, Austria
• ³ Center for International Blood and Marrow Transplant Research, National Marrow Donor Program, Minneapolis, Minnesota, United States
• ⁴ Saatzucht Donau GmbH & CoKG, Reichersberg, Austria
• ⁵ Department of Plant Sciences, Norwegian University of Life Sciences, As, Akershus, Norway
• ⁶ Institute for Crop Science and Plant Breeding, Bavarian State Research Center for Agriculture (LfL), Freising, Bavaria, Germany
• ⁷ Summerland Research and Development Centre, Agriculture and Agri-Food Canada (AAFC), Summerland, British Columbia, Canada
• ⁸ Secobra Saatzucht GmbH, Moosburg an der Isar, Germany
• ⁹ Department of Biotechnology and Plant Biology - Centre for Biotechnology and Plant Genomics, Universidad Politécnica de Madrid, Madrid, Spain
• ¹⁰ Saatzucht Donau GesmbH. & CoKG, Probstdorf, Austria
• ¹¹ University of Natural Resources and Life Sciences Vienna, Tulln an der Donau, Lower Austria, Austria

Fusarium head blight (FHB) is a devastating disease of wheat, causing yield losses, reduced grain quality, and mycotoxin contamination. Breeding can mitigate the severity of FHB epidemics, especially with genomics-assisted methods. The mechanisms underlying resistance to FHB in wheat have been extensively studied, including phenological traits and genome-wide markers associated with FHB severity. Here we aimed to improve genomic prediction for FHB resistance across breeding programs by incorporating FHB-correlated traits and FHB-associated loci as model covariates. We combined phenotypic data on FHB severity, anthesis date, and plant height with genome-wide marker data from five Central European winter wheat breeding programs for genomewide association studies (GWAS) and genomic prediction. Within all populations, FHB was correlated with anthesis date and/or plant height and a marker linked to the semi-dwarfing locus Rht-D1 was detected with GWAS for FHB. Including the Rht-D1 marker, anthesis date, and/or plant height as covariates in genomic prediction modeling improved prediction accuracy not only within populations but also in cross-population scenarios.