Lecture 7 Fungal Phyla Flashcards
How many fungal phyla are there ?
5
fungal phyla are distinguished by?
reproductive features
5 fungal phylum
Chytridiomycota (chytrids)
Zygomycota (Zygote fungi)
Glomeromycota (arbuscular mycorrhizal fungi)
Ascomycota (sac fungi)
Basidiomycota (club fungi)
Distinguishing feature of chytrids
Flagellated spores
Distinguishing feature of zygote fungi
Resistant zygosporangium at sexual stage
Distinguishing feature of glomeromycota
form arbuscular mycorrhizae with plants
Distinguishing feature of ascomycota
sexual spores (ascospores) borne internally in sacs called asci; ascomycetes also produce vast numbers of asexual spores (conidia)
Distinguishing feature of Basidiomycota
Elaborate fruiting body (basidiocarp) containing many basidia that produce sexual spores (basidiospores)
Chytridiomycota Division
Mainly found in water environments.
Initially categorised within Protista.
Reclassified as a fungal group.
Characteristics of Chytridiomycota
- Some species are saprobes while others parasitize protists, plants and animals
- Chitinous cell wall
- Flagellated zoospores
Zygomycota Division
- Zygote fungi or bread molds.
- Fusion of “mated” hyphal strands forming a zygote.
Characteristics of Zygomycota
- Hyphae lack septa
- Found in soil, water, or decaying materials.
- Asexual spores produced in sporangia.
- Sexual reproduction occurs between + and – strains, forming a 2n zygote. Zygospore lies dormant before germination.
- Meiosis occurs just before germination.
- Some species act as parasites or pathogens.
Ascomycota Division
Sac Fungi: Includes unicellular yeasts and complex multicellular cup fungi.
Septated Hyphae: Hyphae are partitioned with septa.
Characteristics of Ascomycota:
Asexual Reproduction
Sexual Reproduction
Ecological Roles
Asexual Reproduction:
Conidia Formation: Specialized hyphal tips produce conidia (haploid asexual spore chains).
Sexual Reproduction:
Mycelia Fusion: Haploid mycelia from different mating strains fuse.
Ecological Roles:
Act as decomposers, pathogens, and engage in symbiotic relationships, notably forming lichens.
Basidiomycota Division
Known as important decomposers of wood, leaves, and plant material.
Diverse Members: Includes mycorrhiza-forming mutualists, mushroom-shaped fungi, and plant parasites (Rusts and Smuts).
Characteristics of Basidiomycota
Reproductive Feature:
Dikaryotic Mycelium: Characterized by a dikaryotic mycelium that reproduces sexually via basidiocarp.
Secondary Metabolites:
Production: Known to produce various secondary metabolites.
Development in basidiomycota 1
Haploid basidiospores grow into short-lived haploid mycelia: under certain conditions, plasmogamy occurs
Development in basidiomycota 2
Resulting dikaryotic mycelium grows forming mycorrhiza or mushrooms (basidiocarps)
Development in basidiomycota 3
Mushroom cap supports and protects gills: karyogamy in the terminal, dikaryotic cells lining the gills produces diploid basidia
Development in basidiomycota 4
Resulting basidium immediately undergoes meiosis producing four haploid basidiospores
Development in basidiomycota 5
Asexual reproduction less common than in ascomycetes
Beneficial Effects of Fungi
– Decomposition - nutrient and carbon recycling
– Biosynthetic factories. Can be used to produce drugs, antibiotics, alcohol, acids, food (e.g., fermented products, mushrooms)
– Model organisms for biochemical and genetic studies
Harmful Effects of Fungi
– Destruction of food, lumber, paper, and cloth
– Animal and human diseases, including allergies
– Toxins produced by poisonous mushrooms and within food (e.g., grain, cheese, etc.)
– Plant diseases
