First Report of Anthracnose Caused by Colletotrichum fructicola on Persimmon in Korea

Abstract

Persimmon anthracnose is a major disease affecting fruit quality and yield in persimmon-growing regions, yet information on the species diversity of causal pathogens in Korea remains limited. This study aimed to identify Colletotrichum species associated with anthracnose symptoms on persimmon fruits and to evaluate their pathogenicity. Sixteen fungal isolates were obtained from symptomatic fruits collected pear research center in Naju, Korea, and their morphological characteristics—colony features, conidial morphology, and appressoria— were examined. Multilocus sequence analysis using internal transcribed spacer, actin, β-tubulin, glyceraldehyde-3-phosphate dehydrogenase, chitin synthase I, calmodulin, the intergenic spacer region between Apn2 and Mat1-2-1 (ApMat) was performed to determine species identity and phylogenetic relationships. Phylogenetic analysis revealed that most isolates (87.5%) belonged to Colletotrichum horii. One isolate each of C. siamense and C. fructicola were also identified; notably, C. fructicola represents the first report of this species on persimmon in Korea. Pathogenicity tests showed that all three species induced typical sunken lesions on wounded fruits, and the inoculated pathogens were successfully re-isolated, fulfilling Koch’s postulates. These findings demonstrate that persimmon anthracnose in Korea is caused by multiple Colletotrichum species with clear genetic differentiation. The detection of C. fructicola suggests that the species spectrum of anthracnose pathogens may be broader than previously recognized. This study provides essential baseline information for disease diagnosis, epidemiological monitoring, and the development of resistant cultivars in future breeding programs.