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Slime mold (Gymnomycota). General characteristics Plasmodium-like slimy organism Phargocytic feeding Unicellular or multicellular Somatic stage is protoplasmic stage Cell walls are produce when reproductive stage Cell walls are predominate with cellulose and
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Slime mold (Gymnomycota)
General characteristics Plasmodium-like slimy organism Phargocytic feeding Unicellular or multicellular Somatic stage is protoplasmic stage Cell walls are produce when reproductive stage Cell walls are predominate with cellulose and galactosamine polymers u u u u u u
Slime mold Division Myxomycota (True slime mold) Division Acrasiomycota (Acrasid cellular slime mold) Division Dictyosteliomycota (Dictyostelid cellular slime mold) Division Labyrinthulomycota (Net slime mold) Division Plasmodiophoromycota (Endoparasitic slime mold) Sorocarp Plasmodium
General characteristic Somatic phase is amoeboid cell or plasmodium which can transform to swam cell A resistant stage consisting of sclerotium Spores are produced in fruiting body which is either exosporous peridium or endosporous peridium Engulf food (bacteria) by phagocytosis They are common on moist rotting wood u u u u u Division Myxomycota (True slime mold)
Type of plasmodium Protoplasmodium: plasmodium remain microscropic scale, forms no veins, slow movement and one protoplas- modium form a single sporangium Aplanoplasmodium: develop from protoplasmodium, fine network homogenous plasmodium forming, rapid streaming Phaneroplasmodium: develop from protoplasmodium, massive network granular plasmodium formimg, rhythmic streaming
Aethalium Sporangium Plasmodiocarp Type of fruiting body Sporangium: with/without stalk, hypothallus usually presented Aethalium: cushion-shaped sporophore without stalk Pseudoaethalium: group of sporangium Plasmodiocarp: protoplasm accumulates in some of the main veins of the plasmodium and develop into fruiting body
Type of Capillitium Hollow tube with lime nodes: (lime node is CaCO3 accumulation) Smooth tube without lime nodes: Tube with spine: Tube with spiral thickening:
Some examples of Myxomycota Stemonitis spp.: Stalked sporangium, long collumella, network capillitium L: www.hiddenforest.co.nz/slime/ photos/photo03.htm M: www.hiddenforest.co.nz/.../family/ stemonitaceae/stemo06.htm R: herba.msu.ru/myx/stemonitis/ 25.jpg
Some examples of Myxomycota Ceratiomyxa spp.: Exosporous myxomycetes, unispored sporangia L: www.sharnoffphotos.com/ myxos1.html R: www.bsu.edu/classes/ruch/ msa/geiser/43.jpg Intro myco 29-27, 28
Division Acrasiomycota (Acrasid cellular slime mold) Division Dictyosteliomycota (Dictyostelid cellular slime mold) General characteristic u Somatic phase is uninucleate haploid amoebae uFruiting body is formed by aggregation of myxamoeba to form pseudoplasmodium and develop for sorocarp, where spores are produced. u Fruiting body is generated without peridium u Sexual reproduction is formed by macrocytes u Phargotrophic nutrition u Common found on soil, dung, decaying mushroom and plant material
Character feathers of Acrasid and Dictyostelid cellular slime mold Acrasiomycota Lobose Ansent Unknown Absent Ansent Stalk cell germinate Unclear Biflagellate Unknown Character Pseudopodia of amoebae Spindle pole body Pheromone Migration of slug Prespore vacuoles Sorocarp differentiation Spore and cyst wall Flagella Sexual reproduction Dictyosteliomycota Foliose Present cAMP Present Present No stalk cell germinate Cellulose Non-flagellate Macrocyte
Example of Acrasid and Dictyostelid cellular slime mold Dictyostelium spp.: sorocarp with well-define sori and sorophore, Branch or unbrance L: www.pasteur.fr/recherche/unites/ reac/images/reac_fig3.html R: www.zum.de/Faecher/Materialien/ beck/12/bs12-24.htm
Subdivision Labyrinthulomycota (Net slime mold) General characteristics uExtoplasmic network branch u Anastomosing u With special cell surface organelle termed bothrosome or sagenogen u Biflagellate zoospore
Subdivision Plasmodiophoromycota (Endoparasitic slime mold) General characteristics u Necrotrophic endoparasite of vascular plants and water mold u Multinucleate, naked protoplasms (cannot move as myxamoeba) u Life cycle compose of two phases; sporangial plasmodial and sporogenic plasmodial u Swarm cell (zoospore) with unequal flagella u No fruiting body formation
Life cycle of Plasmodiophoromycota res2.agr.ca/.../bulletin/ plasmodiophora_brassicae_e.htm
Example of Plasmodiophoromycota Plasmodiophora brassicae www.hri.ac.uk/site2/research/ path/virus/clubroot.jpg