| Alternaria | |
|---|---|
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Scientific classification | |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Dothideomycetes |
| Order: | Pleosporales |
| Family: | Pleosporaceae |
| Genus: | Alternaria Nees |
| Species | |
Many, see text | |
Alternaria is a genus offungi that are found worldwide.Alternaria species are known as majorplant pathogens. They are also commonallergens in humans, growing indoors and causinghay fever or hypersensitivity reactions that sometimes lead toasthma. They are present in the humanmycobiome and readily causeopportunistic infections inimmunocompromised people such asAIDS patients.
There were about 600 known species in the genus in 2023 (although in 2008 the Dictionary of Fungi only listed 299[1][2]). They are ubiquitous in the environment and are a natural part offunga almost everywhere. They are normal agents of decay anddecomposition. Thespores are airborne and found in the soil and water, as well as indoors and on objects. The club-shaped spores are single or form long chains. They can grow thick colonies which are usually green, black, or gray.[2]
At least 20% ofagricultural spoilage is caused byAlternaria species, with the most severe losses reaching 80% of yield.[2] Many human health disorders can be caused by these fungi, which grow on skin andmucous membranes, including on the eyeballs and within the respiratory tract. Allergies are common, but serious infections are rare, except in people with compromised immune systems. However, species of this fungal genus are often prolific producers of a variety of toxic compounds. The effects most of these compounds have on animal and plant health are not well known. Many species ofAlternaria modify their secondary metabolites by sulfoconjugation;[3] however, the role of this process is not yet understood. The termsalternariosis andalternariatoxicosis are used for disorders in humans and animals caused by a fungus in this genus.
Not allAlternaria species are pests and pathogens; some have shown promise asbiocontrol agents againstinvasive plant species. Some species have also been reported as endophytic microorganisms with highly bioactive metabolites.[4]
The genus is now known to bepolyphyletic.[5]
As of 5 August 2023[update], theGBIF lists up to 602 species,[7] whileSpecies Fungorum lists about 645 species.[8]
A selected few species are shown here.
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