Alternaria
Encyclopedia
Alternaria is a genus
of ascomycete
fungi. Alternaria species are known as major plant pathogens
. They are also common allergen
s in humans, growing indoors and causing hay fever
or hypersensitivity reactions that sometimes lead to asthma
. They readily cause opportunistic infection
s in immunocompromised people such as AIDS
patients.
There are 299 species in the genus; they are ubiquitous in the environment and are a natural part of fungal flora almost everywhere. They are normal agents of decay and decomposition
. The spore
s 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 black or gray.
At least 20% of agricultural
spoilage is caused by Alternaria species. Many human health disorders can be caused by these fungi, which grow on skin and mucous membrane
s, 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. The terms alternariosis
and alternariatoxicosis are used for disorders in humans and animals caused by a fungus in this genus.
Not all Alternaria species are pests and pathogens; some have shown promise as biocontrol agents
against invasive plant species
.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of ascomycete
Ascomycota
The Ascomycota are a Division/Phylum of the kingdom Fungi, and subkingdom Dikarya. Its members are commonly known as the Sac fungi. They are the largest phylum of Fungi, with over 64,000 species...
fungi. Alternaria species are known as major plant pathogens
Phytopathology
Plant pathology is the scientific study of plant diseases caused by pathogens and environmental conditions . Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants...
. They are also common allergen
Allergen
An allergen is any substance that can cause an allergy. In technical terms, an allergen is a non-parasitic antigen capable of stimulating a type-I hypersensitivity reaction in atopic individuals....
s in humans, growing indoors and causing hay fever
Hay Fever
Hay Fever is a comic play written by Noël Coward in 1924 and first produced in 1925 with Marie Tempest as the first Judith Bliss. Laura Hope Crews played the role in New York...
or hypersensitivity reactions that sometimes lead to asthma
Asthma
Asthma is the common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm. Symptoms include wheezing, coughing, chest tightness, and shortness of breath...
. They readily cause opportunistic infection
Opportunistic infection
An opportunistic infection is an infection caused by pathogens, particularly opportunistic pathogens—those that take advantage of certain situations—such as bacterial, viral, fungal or protozoan infections that usually do not cause disease in a healthy host, one with a healthy immune system...
s in immunocompromised people such as AIDS
AIDS
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome is a disease of the human immune system caused by the human immunodeficiency virus...
patients.
There are 299 species in the genus; they are ubiquitous in the environment and are a natural part of fungal flora almost everywhere. They are normal agents of decay and decomposition
Decomposition
Decomposition is the process by which organic material is broken down into simpler forms of matter. The process is essential for recycling the finite matter that occupies physical space in the biome. Bodies of living organisms begin to decompose shortly after death...
. The spore
Spore
In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoa. According to scientist Dr...
s 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 black or gray.
At least 20% of agricultural
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
spoilage is caused by Alternaria species. Many human health disorders can be caused by these fungi, which grow on skin and mucous membrane
Mucous membrane
The mucous membranes are linings of mostly endodermal origin, covered in epithelium, which are involved in absorption and secretion. They line cavities that are exposed to the external environment and internal organs...
s, 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. The terms alternariosis
Alternariosis
Alternariosis is an infection by alternaria, presenting cutaneously as focal, ulcerated papules and plaques.Treatment with itraconazole has been reported....
and alternariatoxicosis are used for disorders in humans and animals caused by a fungus in this genus.
Not all Alternaria species are pests and pathogens; some have shown promise as biocontrol agents
Biological pest control
Biological control of pests in agriculture is a method of controlling pests that relies on predation, parasitism, herbivory, or other natural mechanisms...
against invasive plant species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
.
Species
Species include:- Alternaria alternataAlternaria alternataAlternaria alternata has been recorded causing leaf spot and other diseases on over 380 host species. It is opportunistic pathogen on numerous hosts causing leaf spots, rots and blights on many plant parts...
- Causes early blight of potato, Leaf spot disease in Withania somnifera and can infest many other plants. It also causes upper respiratory infections in AIDS patients, asthma in people with sensitivity, and has been implicated in chronic rhinosinusitis. - Alternaria arborescens - causes stem canker of tomatoTomatoThe word "tomato" may refer to the plant or the edible, typically red, fruit which it bears. Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler...
- Alternaria arbusti - causes leaf lesions on Asian pearNashi PearPyrus pyrifolia is a pear tree species native to China, Japan, and Korea. The tree's edible fruit is known by many names, including: Asian pear, Chinese pear, Korean pear, Japanese pear, Taiwan pear, and sand pear.....
- Alternaria blumeae - causes lesions on Blumea aurita
- Alternaria brassicaeAlternaria brassicaeAlternaria brassicae is a plant pathogen able to infect most Brassica species including important crops such as brocoli, cabbage and oil seed rape. It causes damping off if infection occurs in younger plants and less severe leaf spot symptoms on infections of older plants.- External links :* * *...
- infests many vegetables and roses - Alternaria brassicicolaAlternaria brassicicolaAlternaria brassicicola is a plant pathogen. It causes brassica dark leaf spot on most Brassica species.- External links :**...
- grows on cole cropsBrassicaceaeBrassicaceae, a medium sized and economically important family of flowering plants , are informally known as the mustards, mustard flowers, the crucifers or the cabbage family.... - Alternaria brunsii - causing cumin bloosem blight
- Alternaria carotiincultae - causes leaf blight on carrotCarrotThe carrot is a root vegetable, usually orange in colour, though purple, red, white, and yellow varieties exist. It has a crisp texture when fresh...
- Alternaria carthamiAlternaria carthamiAlternaria carthami is a plant pathogen.- External links :* *...
- Alternaria cinerariaeAlternaria cinerariaeAlternaria cinerariae is a plant pathogen.- External links :* *...
- Alternaria citriAlternaria citriAlternaria citri is a fungal plant pathogen.- External links :* *...
- Alternaria conjuncta - grows on parsnipParsnipThe parsnip is a root vegetable related to the carrot. Parsnips resemble carrots, but are paler than most carrots and have a sweeter taste, especially when cooked. The buttery, slightly spicy, sweet flavor of cooked mature parsnips is reminiscent of butterscotch, honey, and subtle cardamom...
- Alternaria dauciAlternaria dauciAlternaria dauci is a plant pathogen. Its English name is carrot leaf blight.- External links :* *...
- grows on carrot - Alternaria dianthiAlternaria dianthiAlternaria dianthi is a plant pathogen.- External links :* *...
- Alternaria dianthicolaAlternaria dianthicolaAlternaria dianthicola is a plant pathogen.- External links :**...
- Alternaria euphorbiicolaAlternaria euphorbiicolaAlternaria euphorbiicola is a plant pathogen.- External links :* *...
- infests cole crops - Alternaria gaisen - causes ringspot disease of pear
- Alternaria helianthiAlternaria helianthiAlternaria helianthi is a plant pathogen.- External links :* *...
- Alternaria helianthicolaAlternaria helianthicolaAlternaria helianthicola is a plant pathogen.- External links :* *...
- Alternaria hungarica
- Alternaria infectoria - infests wheatWheatWheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...
- Alternaria japonicaAlternaria japonicaAlternaria japonica is a plant pathogen.- External links :* *...
- infests cole crops - Alternaria leucanthemiAlternaria leucanthemiAlternaria leucanthemi is a plant pathogen.- External links :* *...
- Alternaria limicolaAlternaria limicolaAlternaria limicola is a plant pathogen.- External links :* *...
- Alternaria linicolaAlternaria linicolaAlternaria linicola is a plant pathogen.- External links :* *...
- Alternaria molesta - may cause skin lesions on porpoisePorpoisePorpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. They are distinct from dolphins, although the word "porpoise" has been used to refer to any small dolphin, especially by sailors and fishermen...
s - Alternaria padwickiiAlternaria padwickiiAlternaria padwickii is a plant pathogen that attacks rice. It is associated with the disease stackburn, otherwise known as alternaria leaf spot.- External links :* *...
- Alternaria panaxAlternaria panaxAlternaria panax is a plant pathogen, who causes Alternaria blight of Ginseng.- External links :* * *...
- causes ginsengGinsengGinseng is any one of eleven species of slow-growing perennial plants with fleshy roots, belonging to the genus Panax of the family Araliaceae....
blight - Alternaria petroselini - causes parsleyParsleyParsley is a species of Petroselinum in the family Apiaceae, native to the central Mediterranean region , naturalized elsewhere in Europe, and widely cultivated as an herb, a spice and a vegetable.- Description :Garden parsley is a bright green hairless biennial herbaceous plant in temperate...
leaf blight - Alternaria radicinaAlternaria radicinaAlternaria radicina is a plant pathogen.- External links :* *...
- Alternaria raphaniAlternaria raphaniAlternaria raphani is a plant pathogen.- External links :* *...
- Alternaria saponariaeAlternaria saponariaeAlternaria saponariae is a plant pathogen.- External links :* *...
- Alternaria selini - causes parsley crown decay
- Alternaria senecionisAlternaria senecionisAlternaria senecionis is a fungal plant pathogen.- External links :* *...
- Alternaria solaniAlternaria solaniAlternaria solani is a fungal pathogen, producing a disease in tomato and potato plants called early blight. The pathogen produces distinctive "bullseye" patterned leaf spots and can also cause stem lesions and fruit rot on tomato and tuber blight on potato. Despite the name "early," foliar...
- causes early blight in potatoes and tomatoes - Alternaria smyrnii - infests alexandersAlexandersAlexanders is a cultivated flowering plant, Smyrnium olusatrum, belonging to the family Umbelliferae. It is also known as alisanders, horse parsley and smyrnium. It was known to Theophrastus and Pliny the Elder ....
and parsleys - Alternaria tenuissimaAlternaria tenuissimaAlternaria tenuissima is a plant pathogen.- External links :* *...
- Alternaria triticinaAlternaria triticinaAlternaria triticina is a plant pathogen that causes leaf blight on wheat. It was first identified in India in 1962 and still causes significant yield loss to wheat crops on the Indian subcontinent. The disease causes necrotic leaf lesions and in severe cases seeds will become shriveled....
- Alternaria zinniaeAlternaria zinniaeAlternaria zinniae is a plant pathogen.- External links :* *...