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A phylum of fungi characterized by the presence of asci and ascospores. Some mycologists have moved the class Ascomycetes to the phylum or division level.
Farlex Partner Medical Dictionary © Farlex 2012

Ascomycota (Ascomycotina)

a diverse group of FUNGI that includes moulds with septate (see SEPTUM) HYPHAE and YEASTS. They are called ‘sac fungi’ because their sexual SPORES, ASCOSPORES, are produced in a sac-like ASCUS. Their asexual spores are usually CONIDIOSPORES, formed in long chains at the end of the CONIDIOPHORE. The term conidia means dust, and these spores are easily detached from the conidiophore and float on the air like dust. The group includes the yeasts Saccharomyces, used in brewing and bread making; Aspergillus, which produces such products as citric acid used in foods; Penicillium which produces PENICILLIN, the ANTIBIOTIC, and which can also be used in making certain cheeses; and Neurospora which is used in genetic studies. Other less beneficial members include some that attack valuable plants, for example one ASCOMYCETE is responsible for DUTCH ELM DISEASE, others are PATHOGENS of CEREALS.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005