First report of leaf spot on Korean raspberry caused by Colletotrichum aenigma

During the summers of 2022 and 2023, leaf spots suspected to be anthracnose were observed on the leaves of Rubus crataegifolius (Korean raspberry) grown in an orchard in Gimhae, South Korea. Approximately 20% of the Korean raspberry plants on the farm where the disease was discovered were confirmed to be infected. The morphological features of the fungal isolates were coincident to the descriptions of Colletotrichum gloeosporioides species complex. Phylogenetic analyses of concatenated sequences of the ITS, ACT, CAL, CHS-1, and GAPDH genes identified the causative agent as Colletotrichum aenigma. Pathogenicity tests confirmed that this fungal species is pathogenic to R. crataegifolius. To the best of our knowledge, this is the first report of C. aenigma on Korean raspberry in Korea and the world.