The

fungus A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified ...

''Cochliobolus sativus'' is the teleomorph (sexual stage) of ''Bipolaris sorokiniana'' (anamorph) which is the causal agent of a wide variety of

cereal A cereal is any grass cultivated for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, germ, and bran. Cereal grain crops are grown in greater quantities and provide more foo ...

diseases. The

pathogen In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a ger ...

can infect and cause disease on roots (where it is known as common root rot), leaf and stem, and head tissue. ''C. sativus'' is extremely rare in nature and thus it is the asexual or anamorphic stage which causes infections. The two most common diseases caused by ''B. sorokiniana'' are spot blotch and common root rot, mainly on wheat and barley crops.

Identification

The mycelium of ''B. sorokiniana'' is usually deep olive-brown. New cultures produce abundant simple

conidiophore A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to the ...

s, which may be single or clustered and measure 6–10 x 110–220 μm with septations.

Conidia A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to th ...

develop laterally from pores beneath each conidiophore septum. Conidia are olive-brown and ovate to oblong, with rounded ends and a prominent basal scar. They measure 15–28 x 40–120 μm and are 3- to 10-septate. Some may be slightly curved. Their walls are smooth and noticeably thickened at the septa. Ascus The sexual state (''C. sativus''), when formed in culture, is in the form of black, globose pseudothecia 300–400 μm in diameter, with erect beaks 50–200 μm long.

Asci ASCI or Asci may refer to: * Advertising Standards Council of India * Asci, the plural of ascus, in fungal anatomy * Accelerated Strategic Computing Initiative * American Society for Clinical Investigation * Argus Sour Crude Index * Association of ...

are clavate and measure 20–35 x 150–250 μm. Ascospores are hyaline, uniformly filamentous, and spirally flexed within asci. They measure 5–10 x 200–250 μm and are 4- to 10-septate.

Host species

'' Agropyron cristatum¹, Allium sp. ¹,

Alopecurus pratensis ''Alopecurus pratensis'', known as the meadow foxtail or the field meadow foxtail, is a perennial grass belonging to the grass family (Poaceae). It is native to Europe and Asia. This common plant is found on grasslands, especially on neutral so ...

¹,

Aneurolepidium chinense ''Leymus'' is a genus of plants in the grass family Poaceae (Gramineae). It is widespread across Europe, Asia, and the Americas. * '' Leymus aemulans'' - Xinjiang, Central Asia * '' Leymus ajanensis'' - Siberia, Russian Far East, Alaska ...

¹,

Avena sativa The oat (''Avena sativa''), sometimes called the common oat, is a species of cereal grain grown for its seed, which is known by the same name (usually in the plural, unlike other cereals and pseudocereals). While oats are suitable for human co ...

¹'' '' Bromus inermis¹, B. marginatus¹, B. willdenowii¹'' '' Calluna vulgaris¹, Chloris gayana¹, Cicer arietinum¹, Clinelymus dahuricus¹, C. sibiricus¹,

Cynodon dactylon ''Cynodon dactylon'', commonly known as Bermuda grass, is a grass found worldwide. It is native to Europe, Africa, Australia and much of Asia. It has been introduced to the Americas. Although it is not native to Bermuda, it is an abundant invasi ...

¹, C. transvaalensis¹'' '' Dactylis glomerata¹'' ''

Echinochloa crus-galli ''Echinochloa crus-galli'' is a type of wild grass originating from tropical Asia that was formerly classified as a type of panicum grass. It is commonly known as cockspur (or cockspur grass), barnyard millet, Japanese millet, water grass, common ...

¹, Elymus junceus¹'' ''Festuca sp. ¹'' ''Guzmania sp. ¹'' '' Hordeum brevisubulatum¹, H. distichon¹, H. sativum var. hexastichon¹, H. vulgare¹, H. vulgare var. hexastichon¹'' ''

Lablab purpureus ''Lablab purpureus'' is a species of bean in the family Fabaceae. It is native to Africa and it is cultivated throughout the tropics for food.

¹, Linum usitatissimum¹, Lolium multiflorum¹'' ''

Pennisetum typhoides Pearl millet (''Cenchrus americanus'', commonly known as the synonym ''Pennisetum glaucum''; also known as 'Bajra' in Hindi, 'Sajje' in Kannada, 'Kambu' in Tamil, 'Bajeer' in Kumaoni and 'Maiwa' in Hausa, 'Mexoeira' in Mozambique) is the most ...

¹'' '' Roegneria semicostata¹'' ''Saccharum sp. ¹, Secale cereale¹, Setaria italica¹, Sorghum sp. ¹'' ''

Taraxacum kok-saghyz ''Taraxacum kok-saghyz'', often abbreviated as ''TKS'' and commonly referred to as the Kazakh dandelion, rubber root, or Russian dandelion, is a species of dandelion native to Kazakhstan, Kyrgyzstan and Uzbekistan, that is notable for its product ...

¹,

Trisetum aestivum ''Trisetum'' is a genus of plants in the grass family Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasse ...

¹, Triticum aestivum¹, T. secale¹, T. turgidum subsp. durum, T. vulgare¹’’ ''

Zea mays Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn ( North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. ...

¹''

Notes

1
USDA ARS Fungal Database

Geographical distribution

''Cochliobolus sativus'' has a world-wide distribution.

Notes

1
USDA ARS Fungal Database

Main diseases

Common root rot (barley); Common root rot (wheat);

spot blotch (barley) Spot blotch is a disease of barley caused by ''Cochliobolus sativus The fungus ''Cochliobolus sativus'' is the teleomorph (sexual stage) of ''Bipolaris sorokiniana'' (anamorph) which is the causal agent of a wide variety of cereal diseases. The ...

; Spot blotch (wheat)

Spot blotch of wheat

This is most important disease in non-tradition wheat growing areas. The ''B. sorokiniana'' comes with '' Pyrenophora tritici-repentis'' and causes millions of tons of wheat loss each year. The symptoms are blotch as well as induced senescence due to premature chlorophyll losse
Rosyara et al., 2007

References

External links

Index Fungorum

USDA ARS Fungal Database

Diagnosis of Common Root Rot of Wheat and Barley
{{Taxonbar, from=Q5139370 Fungal plant pathogens and diseases Cereal diseases Barley diseases Wheat diseases Cochliobolus Fungi described in 1890