Aspergillus niger

From Pestinfo-Wiki
Jump to: navigation, search

Literature database
186 articles sorted by:
year (recent ones first)
research topics
host plants
list of antagonists
Aspergillus niger agar culture (click on image to enlarge it)
Source: Wikimedia Commons

Aspergillus niger Tiegh. 1867

This is a very common saprophytic fungus which has a world-wide distribution and causes rots and moulds on stored products, especially under warm and humid conditions. Being common in soil and decaying plant material, it can also infects various crops in the field like groundnut (crown-rot) or onion (black mould disease). Such infection can result to significant yield losses. On grapevine it causes vine canker and contaminates grapes with various mycotoxins, e.g. ochratoxin A.

Apart from health risks due to mycotoxins, it can also cause allergies. Infections of the ear, lungs or skin have been mainly reported from patients already suffering from other diseases. The fungus is used in the industrial production of certain enzymes and organic acids.

Vernacular names
• Deutsch: Schwarzer Gießkannenschimmel
• English: black mould of vegetables
crown-rot of groundnut
• Español: moho negro de la cebolla
• Français: aspergille noir
pourriture du collet de l'arachide
moisissure noire du bulbe de l'oignon

Under certain conditions, germinating groundnuts become infected with the fungus, resulting in crown rot. In some cases 50% losses have been reported. The area just below the soil line becomes covered with mycelia and black spores, the seedlings wilt and die after a few weeks. Fungicide treated seeds are recommended if fields have a history of crown rot.

On grapes, A. niger causes black rot, infecting mainly the berry skin. About 4-10% of the strains can produce ochratoxin A (nearly 100% for Aspergillus carbonarius). Some strains produce fumonisin B which can also contaminate grapes and wine. Onions commonly become infected with A. niger in the field which then causes black mould in storage under warm and humid conditions. Some onion varieties are resistant to the disease.

A. niger grows at a wide temperature range (6-47°C). The conidia-bearing hyphae are similar to those of other Aspergillus species and have a swollen, spherical apex, 40–75 µm in diameter. The conidia are also spherical, 4-5 µm large, and are produced in chains.

A. niger is a member of Aspergillus section Nigri, a group of 26 species that are characterized by black conidia and are often called the "black Aspergilli". The group includes A. carbonarius, Aspergillus japonicus and Aspergillus awamori. For a taxonomical review of this group, see Varga et al., 2011.