Phylum Ascomycota, Genus Sordaria

Habitat

Living as a fairly loose mycelium on dung and decaying plant material.

Friends

Morels (Morchella) can be found in Saskatchewan. They are teh ascocarps of a subterranean fungus. Morels are not mushrooms; only phylum Basidiomycota produce structures called basidiocarps which are true mushrooms. Ergot infection of grains, primarily rye, is caused by the fungus Claviceps. The overwintering stage of this fungus (sclerotia) looks like long black kernels within the head of rye. The sclerotia are very poisonous when eaten by grazing animals or humans. Ergot poisoning causes insanity, convulsions, cardiovascular collapse and gangrene of the extremities and is often fatal. It was the cause of the medieval disease St. Anthony's Fire, and is thought to have been a factor in the Salem witch trials.

Mycelium

The body of the fungus which is comprised of many hyphae.

Adaptation

The neck of the flask-shaped ascocarp grows toward the light, directing the asci (and ascospores) up through the gaps in the surrounding vegetation. This adaptation ensures that when the ascospores are released, they will be directed to land on fresh vegetation, where the spores will be ingested and dispersed by herbivores. When the ascospores are mature, they are forcibly ejected out of the asci through a pore at the tip of the ascocarp. The ascospores are shot as much as 60mm away from the ascocarp, which is another adaptation to ensure the spores are deposited away from the ascocarp and onto living plant material. The ascospores are coated with a sticky, gelatinous material which allows the spores to adhere to vegetation.

Ascus

The sac-like cell within which meiosis occurs to produce ascospores in fungi of the phylum Asomycota.

Ascospore

A reproductive cell produced within an ascus in fungi of the phylum Ascomycota.

Ascocarp

A reproductive structure of fungi of the phylum Ascomycota which produces asci and ascospores. The ascocarp in Sordaria is formed during sexual reproduction and is brown and flask-shaped.

Asexual or sexual?

Asexual reproduction is rare in this group.

Sordaria

Domain Eukarya, Kingdom Fungi, Phylum Ascomycota, Genus Sordaria Common name: dung dweller?

Phylum Ascomycota

Phylum Ascomycota is the largest of the fungal phyla, containing more than 30,000 species. Includes cup fungi, powdery mildews, yeasts, morels and truffles. Most terrestrial saprotrophs, some are plant pathogens , causing diseases such as ergot of wheat or rye, and dutch elm disease. They have septa or cross walls in their hyphae so the hyphal strands are separated into individual cells, each with a single haploid nucleus. Most members reproduce asexually. The phylum name is derived from askos - meaning bag or sac. This refers to the sac-like sexual reproductive structure called an ascus - produced by most of these fungi. Asci, contained in a protective structure called an ascocarp, far formed during sexual reproduction when the haploid hyphae of two mating strains come into contact. Meiosis occurs in each ascus to produce haploid ascospores. When an ascospore is released from the ascus and lands in a suitable environment, it can grow into haploid hyphae, completing the life cycle.