Systematic surveillance of Fusarium head blight in the southern region of the Republic of Korea.

Fusarium head blight (FHB), caused by species complex, is one of the most destructive plant diseases affecting wheat and barley globally. However, effective management methods remain elusive because of limited availability of resistant cultivars. Accordingly, systematic surveillance is one of the key strategies, allowing for prompt responses to emerging outbreaks and supporting the establishment of preventive guidelines for future occurrences. FHB severity in the southern region of the Republic of Korea in 2024 following an outbreak was systematically monitored. A total of 100 wheat ( = 43) and barley ( = 57) fields were assessed for FHB indices and mycotoxin concentrations. A geographical breakdown showed that several regions were heavily impacted by the FHB outbreak, with elevated disease severity exceeding 50%. Furthermore, spatiotemporal analysis of the FHB outbreak revealed relatively high disease severity in 2024, ranging from 3- to 6-fold compared to the previous years, likely influenced by climatic factors. A strong correlation of FHB severity and nivalenol concentrations was also observed, with concerning levels that underscore potential risk for future FHB outbreaks. These findings provide valuable insights into the epidemiology of FHB in the Republic of Korea and will help guide the development of more effective management strategies for FHB and its associated mycotoxins.