Taxonomy a classification of organisms into groups based on similarities of structure or origin etc.

KINGDOM CHARACTERISTIC EXAMPLE Monera Prokaryocyte Bacteria   Monera Prokaryocyte Bacteria Actinomyces Protista Eukaryocyte Protozoa Fungi Eukaryocyte * Plants Moss Animals Arthropods Mammals Man  

KINGDOM CHARACTERISTIC EXAMPLE Monera Prokaryocyte Bacteria   Monera Prokaryocyte Bacteria Actinomyces Protista Eukaryocyte Protozoa Fungi Eukaryocyte * Plants Moss Animals Arthropods Mammals Man  

Classification of Fungi Kingdom Fungi Division -mycota Subdivision -mycotina Class -mycetae Subclass -mycetes Order -ales Family -aceae Genus -------- Species --------

Classification of Fungi Four major division of fungi, base on the type of sexual spores (ascospore, basidiospore, zygospore, oospore), plus another group, which have no know sexual state. Chytridiomycota Zygomycota Ascomycota Basidiomycota Deuteromycota (Imperfect fungi)

Classification & Phylogeny asci basidia The phyla of fungi are determined by 1. motility of spores 2. nature of sexual stage Fungi moved onto land with the plants in the Early Paleozoic Much of the evolution of fungi was in conjunction with the evolution of plants and plant parts For example, when roots evolved, fungi were there and helped (mycorrhizas) When wood evolved, fungi evolved to take advantage of it Other evolutionary changes related to animals zygosporangia Classification & Phylogeny motile spores

Chytridiomycota – “chytrids” Simple fungi Produce motile spores - zoospores Mostly saprobes and parasites in aquatic habitats Could just as well be Protists Chytridium growing on spores Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material) Chytriomyces growing on pine pollen

Cell walls contain chitin and glucan ‘Chytrids’ are considered the earliest branch of the true fungi (Eumycota) Cell walls contain chitin and glucan Only true fungi that produce motile, flagellated zoospores – Usually single, posterior whiplash type – Some species have multiple flagella Zoospore ultrastructure is taxonomically important within this phylum Commonly found in soils or aquatic environments, chytrids have a significant role in degrading organics Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)

A few are obligate intracellular parasites of plants, algae, and small animals (e.g., frogs) Very few economically important species (Synchytrium endobioticum causes potato wart disease) More important (and fascinating) as biological models (e.g, Allomyces). Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)

Zygomycota – “zygote fungi” Rhizopus on strawberries Sexual Reproduction - zygosporangia Asexual reprod. – common (sporangia – bags of asexual spores) Hyphae have no cross walls Grow rapidly Decomposers, pathogens, and some form mycorrhizal associations with plants Most of the 600 zygomycote, or zygote fungi, are terrestrial, living in soil or on decaying plant and animal material. Asexual reproduction in sporangia One zygomycote group form mycorrhizas, mutualistic associations with the roots of plants. Rhinocerebral zygomycosis

Five features of Phylum Zygomycota – Cell walls contain chitin, chitosan, and polyglucuronic acid – Some members typically bear multinucleate, coenocytic hyphae, i.e., without cross walls (septa; sing., septum) • When present, septa are simple partitions • Some Orders have regular septations that are flared having a centrally plugged pore – Produce zygospores (meiospore). Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)

Importance of the zygomycetous fungi – Organic degraders/recyclers – Asexual spores (mitospores), termed sporangiospores, form through cytoplasmic cleavage within a sac-like structure termed a sporangium – Haploid genome Importance of the zygomycetous fungi – Organic degraders/recyclers – Useful in foodstuffs/fermentations – Pathogens of insects/other animals Generalized life cycle – Asexual stage (anamorphic; imperfect) • A thin-walled sac (sporangium) is walled off at the tip and fills with cytoplasm Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)

• containing multiple nuclei (with collumella underneath sac) • Cytoplasmic cleavage and separation of nuclei into walled units produces sporangiospores • Thin sporangial wall (peridium) breaks releasing sporangiospores • Sporangiospores germinate to repeat the asexual life cycle Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)

The zygospore represents the teleomorphic phase (sexual; perfect form) of this phylum – Results from the fusion of gametangia of heterothallic (two different mating types; designated “+” and “-”) or homothallic (self fertile) strains Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)

– Acts as a thick-walled resting spore • Zygosporangium becomes thick walled to form the zygospore • Hyphae to the sides become empty appendages (suspensor cells) • Zygospore often forms ornate appendages • Zygospore is constitutively dormant for a time, but then germinates to produce a sporangium containing haploid sporangiospores Classified in CMR as true fungi (because of their molecular relationships) Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)

Life cycle of Rhizopus Sexual zygsporangium with one zygospore Asexual sporangium with spores inside Life cycle of Rhizopus

Ascomycota – “sac fungi” Sexual Reproduction – asci (sing. = ascus) Asex. Reprod. – common Cup fungi, morels, truffles Important plant parasites & saprobes Yeast - Saccharomyces Decomposers, pathogens, and found in most lichens Mycologists have described over 60,000 species of ascomycetes, or sac fungi. Ascomycota tend to grow from spore to spore in one year and relate well to living plant tissues There is diverse form in the growth and fruiting structures – yeasts to morels, many intermediate (and small) Asexual reproduction by conidia (externally produced, not in sporangia) Half of the Ascomycota form lichens (evolved 8 or more times in different orders) but not all lichens are Ascomycotes A cluster of asci with spores inside

Life cycle of Ascomycetes

Apothecium Perithecium - Perithecium - Apothecium - Cleistothecium Ascocarp Cleistothecium

Basidiomycota – “club fungi” Sexual Reproduction – basidia Asexual reprod – not so common Long-lived dikaryotic mycelia Rusts & smuts –plant parasites Mushrooms, polypores, puffballs, boletes, bird’s nest fungi Enzymes decompose wood, leaves, and other organic materials Decomposers, pathogens, and some form mycorrhizal associations with plants Asexual spores conidia Ecologically important on wood as decomposers and parasites Half the mushrooms form mycorrhizas SEM of basidia and spores

Clamp connection

Life cycle of basidiomycetes

Some fungi have more than one scientific name – Why? Teleomorph: the sexual reproductive stage (morph), typically a fruiting body (e.g., Morchella esculenta, Agaricus brunescens). Anamorph: an asexual reproductive stage (morph), often mold-like (e.g. Aspergillus flavus, Fusarium solani). Holomorph: the whole fungus, including all anamorphs and the teleomorph.

Deuteromycota – Form Phylum “Imperfect Fungi” Fungi that seldom or never reproduce sexually. Asexual reproduction by vegetative growth and production of asexual spores common.

HUMAN-FUNGUS INTERACTIONS 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.