Classification of Fungi by G. M. Smith (1955) Dr. Prachi Kshirsagar

A system of classification of fungi Smith, G.M. (1938). Cryptogamic Botany, vol. 1. Algae and fungi. Smith, G.M. (1955). Cryptogamic Botany, vol. 2. Bryophytes and pteridophytes. 2 – division and 7 classes Classification of fungi based on following features Nature of somatic (Vegetative) phase (Unicellular or multicellular – septate or aseptate) Nature of asexual spore (sporangiospore and conidia) If sporangiospore (motile/non-motile; no., form and arrangement of flagella) Kinds of sporangia Presence or absence of sexual reproduction

Myxomycophyta Eumycophyta (Slime Moulds) (True Fungi) Subkingdom Fungi Division Myxomycophyta Eumycophyta (Slime Moulds) (True Fungi) Class 1. Myxomycetae 1. Phycomycetae (Algal fungi) 2. Plasmdiophoreae 2. Ascomycetae (Sac fungi) 3. Aerasieae 3. Basidiomycetae (Club fungi) 4. Deuteromycetae (Imperfect)

Division I - Myxomycophyta Salient Feature:- Feed on bacteria and other organic particles Thallus non-green, multinucleate (diploid) mass of protoplasm (Plasmodium – amoeboid in shape) Plasmodium naked; it doesn’t possess limiting cell wall Reproduces by uni-nucleate spore with distinct wall Members are free-living, diploid and holocarpic Classified under PROTIST (organism neither plant nor animal)under five kingdom classification system Found on damp forest, under logs, on dead organic material`

Division I - Myxomycophyta Fuligo septica (Dog vomit slime mold) Trichia varia Hemitrichia serpula

Class – Myxomycetae (Myxomycophyta) Plasmodia free living, large (several cm) Plasmodia are non-parasitic; grow on substratum, highly colored Nutrition holozoic (engulfing food like amoeba) Creeps on substratum like amoeba Sporangia have outer wall (Peridium) Spores also have definite wall Flagella – Whiplash and Tinsel Sexual reproduction by fusion of biflagellate gametes Divided into 2 sub-class 1. Endosporeae 2. Exosporeae 60 genera and 400 sp. e.g. Didymium, Physarum, Stemonitis, Hemitrichia

Class – Myxomycetae (Myxomycophyta) Stemonitis sp. Didymium sp.

Class – Plasmodiophoreae (Myxomycophyta) Large, multinucleate, naked plasmodium Vegetative development takes place within the living tissue of the host plant Nutrition – parasitic Spore possess wall Flagella dissimilar Spore germinate to form biflagellate swarmer e.g. Plasmodiophora (Obligate parasite)

Class – Plasmodiophoreae (Myxomycophyta) Plasmodiophora causing disease to brassicaceae (Club root)

Class – Acrasieae (Myxomycophyta) Members are free living Multinucleate plasmodium absent Swarmers are totally absent (flagella absent) Large no. of uninucleate myxamoebae fuse to from pseudoplasmodium Myxamoebae retains its individuality Pseudoplasmodium forms a sorocarp (fruiting body) Sorocarp has distinct sterile and fertile region E.g. Dictyostellium

Class – Acrasieae (Myxomycophyta) Dictyostellium discoedium – fruting body Dictyostellium discoedium - vegetative Dictyostellium sp.

Division II - Eumycophyta Possess definite cell wall Thallus filamentous Hypha branched or unbranched, septate/aseptate (Coenocytic) Heterotrophic (Saprophyte or parasite) Asexual reproduction occurs by variety of spore Sexual reproduction absent in Deuteromycetes Sexual reproduction by 1. Plasmogamy 2. Karyogamy 3.700 genera and 36,000 sp. Have 4 classes 1. Phycomycetae 2. Ascomycetae 3. Basidiomycetae 4. Deuteromycetae

Division II - Eumycophyta Saccharomyces Sp. Rhizopus Sp. Polyporus Agaricus Sp.

Class – Phycomycetae – Algal Fungi (Eumycophyta) Shares character with algae Terrestrial (Mucor, Rhizophus), Aquatic (Saprolegnia) Thallus unicellular (Synchetrium); filamentous uni or multinucleate coenocytic hypha (Mucor, Cystopus) Parasitic or saprobes Asexual reproduction- naked zoospore (uni/biflagellate) Sexual reproduction: Isogamous, Anisogamous or oogamous (Planogametic copulation) Plasmogamy immediately followed by karyogamy First division of fertilization is meiosis (reduction divission) Thus diploid phase is shot duration e.g. Synchetrium, Pythium, Phytopthora, Cystopus, Mucor, Rhizophus

Class – Phycomycetae (Eumycophyta) Saprolegnia Sp. (Aquatic) Mucor Sp. Pythium Sp. Albugo Sp.

Class – Ascomycetae – Sac Fungi (Eumycophyta) Characteristic ascospore (Meiospore) produced inside a Ascus (sac) Thallus mycellial type except Yeast and some other members Mycellium multicellular, septate with a central pore Motile cell absent Asexual reproduction – conidia (exogenous) Sexual reproduction oogamous in primitive Separate male and female sex organs formed i.e. Ascogonia and Anthredia Plasmogamy not immediately followed by Karyogamy thus establishes a dikaryon Karyogamy immediately followed by meiosis Karyogamy and meiosis occurs in Ascus foming ascospore (8) Asci produced in Ascocarp (Fruiting body) e.g. Saccharomyces, Claviceps, Penicillium, Aspergillus

Class – Ascomycetae (Eumycophyta) Penicillium Sp. Saccharomyces Sp. Aspergillus Sp.

Class – Basidiomycetae – Club Fungi (Eumycophyta) Includes Mushroom and their allies, jelly fungi, smuts and rust Mycellium has 2 phases 1. Primary – made up of uninucleate cells (Monokaryotic phase) 2. Secondary – made up of binucleate cells (Dikaryotic phase – nuclei from 2 different strain) Asexual reproduction by spore (Rare) Motile cells absent Sexual reproduction through fusion of primary hypha (no special reproductive structure) Sexual reproduction: Plasmogamy (nuclei transfer), Karyogamy and Meiosis Dikaryotic mycellium produces Basidiocarp Basidiospores forms in Basidium (Sporangium) Basidiospores (Meiospore) arranged on Sterigmata No. of basidiospore (4), exceptionally (2-8)

Class – Basidiomycetae (Eumycophyta) Puccinia Sp. (Wheat Rust) Agaricus Sp. (Mushroom) Polyporus Sp. (Bracket Fungi) Geastrum Sp. (Earth Star)

Class – Deuteromycetae – Imperfect Fungi (Eumycophyta) Perfect stage i.e. sexual stage absent or not known so far Fungi don’t form zygote, ascospore or basidiospore Hypha septate, cells may be uni, bi or multinucleate Saprophyte or parasite Asexual reproduction – conidia, blastospore, chlamydospore Mycelia sterila – spores are not form at all e.g. Alternaria Sp., Curvularia Sp., Cercospora Sp., Colletotrichum Sp., Fusarium Sp.

Class – Deuteromycetae (Eumycophyta) Alternaria Sp. Fusarium Sp. Colletotrichum Sp. Cercospora Sp.

Life cycle pattern in Cystopus (Albugo) Dr. Prachi Kshirsagar

Systematic position in Albugo (G. M. Smith) Division: Eumycophyta – Presence of definite cell wall (fungal cellulose) Plant body mycelium, uni or multicellular Class: Phycomycetae – Mycellium asepate, coenocytic, branched Spores many i.e. conidia Subclass: Biflagellatae – Asexual reproduction by means of biflagellate Zoospore Sexual reproduction oogamous Order: Peronosporales – Sporangia function as conidia, Sporangia detach from mycellium Family: Albuginaceae – Obligate parasite, Sexual reprodcution oogamous (Oospores are formed) Myceium intercellular Genus : Cystopus (Albugo) Produce rust like pustules on leaves hence called as ‘white rust’ Asexual reproduction by chains of conidia which are in basipetal manner

Albugo - Introduction