First Repot of Leaf Spot Disease Caused by Cladosporium allicinum on Barley in Korea

Barley (Hordeum vulgare) is one of the major winter cereal crops in Korea. In April 2021, barley plants showing leaf spot symptoms were observed in Boseong-gun and Jangheung-gun, Jeollanam-do, Korea. Morphological characteristics and multi-locus sequence analyses identified Cladosporium allicinum as the causal pathogen. Pathogenicity assays reproduced the symptoms on barley leaves, and the pathogen was successfully reisolated, fulfilling Koch’s postulates. This study constitutes the first report of C. allicinum causing leaf spot on barley in Korea and expands the known host range of this species, providing a foundation for future disease management strategies.