Pathogenicity of the fern anthracnose fungus, Colletotrichum acutatum, on wild and cultivated ferns in Florida

摘要

The fern anthracnose pathogen Colletotrichum acutatum. H. Simmonds is now well-established in leatherleaf fern production systems throughout Central Florida. Fern anthracnose is the most significant disease that affects leatherleaf fern production. In controlled-environment experiments, C. acutatum was also found to infect several wild fern species which occur in natural habitats near fern production systems; some of these ferns are regarded as weeds, or potential weed species. Thus far, however, the fungus has not been detected on susceptible wild fern species growing in their natural habitats. Several, but not all, cultivated fern species which are likely to be produced by horticulturists for planting in Florida landscapes were also tested and found to be susceptible to fern anthracnose. Infection of both wild and cultivated fern species resulted in varying levels of disease damage which depended greatly on the growth habit of the species. As the pathogen can be easily spread by workers or equipment during outdoor nursery production and, to a lesser degree, in greenhouse facilities, these results indicate potential disease hazards for cultivated ferns and identify possible sources of inoculum and opportunities for the survival and persistence of C. acutatum in the absence of its primary host.