Diversity and Distribution of the Rice Blast Races in Korea between 2023 and 2024

Rice blast, caused by Magnaporthe oryzae, is one of the most damaging diseases limiting rice production worldwide. Developing and deploying resistant cultivars remains the most reliable strategy for managing the rice blast disease. However, resistance in rice cultivars is often short-lived because the blast pathogen rapidly evolves and adapts to newly released cultivars. This makes continuous surveillance of pathogen populations and their virulence dynamics essential. To assess the current population structure and shifts in resistance effectiveness in Korea, 736 isolates were collected from seven provinces between 2023 and 2024 and evaluated for their pathogenic reactions on the susceptible cultivar ‘Lijiangxintuanheigu’ (LTH) and 27 LTH-based monogenic resistance lines. The results showed that Piz-5 and Pita-CP1 exhibited over 90% resistance to rice blast isolates collected in 2023 and 2024. The findings of this study improve our understanding of pathogen population dynamics and provide valuable guidance for developing rice cultivars with enhanced blast resistance in Korea.