Abstract
In 1994, young fruit apex rot of the citrus cultivar 'Shiranui' was found in Kumamoto Prefecture. The causal agent was confirmed to be a fungus by inoculation test. Judging from the characteristics of the fungus, colonial color, conidia shape and size, appressoria shape and size and hyphal growth of 15-35°C, the pathogen was identified as Colletotrichum gloeosporioides. It was proved that the pathogen successfully infected to detached leaves of 'Shiranui' and its parents 'Kiyonmi' and 'Ponkan', but could not infect 'Kawano-natsudaidai'.
