Mitosporic fungus. Hyphomycetes. Anamorphic Pleosporaceae.
Approx. 40-50 species.
Soil, dead organic debris, on food stuffs and textiles. Plant pathogen, most commonly on weakened plants.
On a variety of substrates.
Aw=0.85-0.88 (minimum for various species)
Biocontrol of weeds and other plants.
One of the most common fungi worldwide.
Type I allergies (hay fever, asthma).
Type III hypersensitivity pneumonitis: Woodworker's lung, Apple store hypersensitivity.
May cross react with Ulocladium, Stemphylium, Phoma, others.
Nasal lesions, subcutaneous lesions, nail infections; the majority of infections reported from persons with underlying disease or in those taking immunosuppressive drugs. Most species of Alternaria do not grow at 37°C.
A. alternata produces the antifungal alternariol. Other metabolites include AME (alternariol monomethylether), tenuazonic acid, and altertoxins (mutagenic).
Grows well on general fungal media. Colonies are dark olive green to brown, floccose to velvety (heavily sporulating). Colonies become pleomorphic over time, and lose the ability to sporulate with subsequent transfer.
Distinctive. Young spores or spore fragments may be confused with Ulocladium, Pithomyces, Stemphylium, or Epicoccum. (Some Alternaria species cannot be separated from Ulocladium.)
Distinctive. Readily identifiable on tape lift samples.