Anthracnose is a primary colonizer of injured and senescent tissue. The organism grows on dead wood in the canopy, and it spreads short distances by rain splash, heavy dew, and overhead irrigation. Such movement deposits the spores on susceptible tissues of young leaves or immature fruit. Sexual spores, although less numerous, are significant for long distance dispersal because of their ability to become airborne. Once the spores germinate, they form a resting structure that allows them to remain dormant until an injury occurs or until degreening. The disease is especially troublesome on fruit that are harvested early and degreened for over 24 hours because ethylene stimulates the growth of the fungus.
Serrano, D., Serrano, E., Dewdney, M., and Southwick, C. (2010). Citrus Diseases. USDA/APHIS/PPQ Center for Plant Health Science and Technology. [09-14]