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1. Fungus-Like Protozoans Mycology (Bio 594, Special Topics) M. Marshall 2013 Shippensburg University (See last slide for credits)

2. Carl Linnaeus (1707-1778) the “Father of Taxonomy” • “Minerals exist; plants exist and live; animals exist, live and sense.” • Plants without obvious sexual organs were classified in Class Cryptogamia (lichens, fungi, mosses, ferns) • Fungi are primitive plants under this classification of organisms. @

3. Two Kingdom System In the not-so-distant past all life was considered to be either plant or animal @

4. Science 163: 150-160 (1969) @

5. R. H. Whittaker’s 1969 Classification

6. Modern Classification At least 7 kingdoms are now recognized: • Eubacteria, Archaebacteria, Animalia, Plantae, Eumycota, Stramenopila (Chromista ?), Protoctista (Protozoa, Protista) • Some proposed revisions split the protozoans up into even more kingdoms (see slide after next) • The kingdoms shown in Blue contain fungus-like organisms, some of which (now in the Stramenopila ?) were considered true fungi until relatively recently.

7. The seven Kingdom system according to your text (now outdated) Kingdoms in Blue contain fungi or fungus-like organisms

8. The evolution of “large scale”systematics has been substantial, but things are still a mess at present

9. The problem with Protozoans It seems clear that the Protozoa as they are now constructed, which in itself has always been controversial, will not stand. The relationships among members of this kingdom are in some case so remote that it seems almost certain that it will eventually be fragmented into several more Kingdoms. There is a fair amount of consensus that theChromistidsshould exist as a distinct Kingdom separate from protozoans, and that the Oomycete “watermolds” should be placed there instead of in their former position (along with the Zygomycetes) in the Phylum Phycomycota. So the Pythiums, Phytophthoras, Saprolegnias, Peronosporalesand so on – all of which have aquaticmotile zoospores – are no longer considered true fungi. The other protozoan category of fungus-like organisms has always been considered protozoans; these are thefree-livingplasmodialand cellular slime molds andthe Plasmodiophorids, which are slime mold – like obligate endoparasites of plant roots. These are placed in theEumycetozoa of the Amoeboza as the cells move via cytoplasmic streaming.

10. A (doubtless out of date) Historical Overview PROTOZOANSEUMYCOTA (True fungi) Chromista ?Phycomycetes * PhythophthoraOomycetes Pythium Plasmopara Peronospora(moved) ZYGOMYCOTA* (incl. Glomeromycota) Amoebozoa MYXOSTELIDA CHYTRIDIOMYCOTA* (Myxomycetes) (Blastocladiales, true Chytrids plasmodial slime molds and others) DICTYOSTELIDA ASCOMYCOTA* (Acrasiomycetes) cellular slime molds BASIDIOMYCOTA* PLASMODIOPHORA All OTHER PROTOZOAN GROUPS Deuteromycetes* (artificial Form Phylum & subdivisions based on asexual structs. only) * all ended in – cetes and were considered classes; grayed out = no longer a valid taxa Sex = oospores zoospores Sex = zygospores swarm cells Sex = ascospores amoeba Sex = basidiospores zoospores

11. At the moment (2013) things look like this . . . From the Tree of Life web projecthttp://tolweb.org/tree/phylogeny.html

12. Physarumpolycephalum, a plasmodial slime mold Contrast to Fig 2.1 in BK Fifth Kingdom book

13. Physarum plasmodium, essentially one huge multinucleate cell

14. Plasmodia differentiate into a colony of sessile fungus-like sporangia Hemitriciaclavata Myxomycetes are classified according to the structure of the sporangia. In some the differentiation into delicate stalked structures is quite complex, in others the plasmodium seems to merely collect itself a bit and harden in place

15. Myxomycota sporangia A & B Sporangia of Arcyria and Stemonitis C. An aethalium (no stalk) of Lycogola spp. D. a plasmodiocarp(the plasmodium veins thicken and harden of Hemitrichia spp. (thanks to Tom Volk, http://botit.botany.wisc.edu/toms_fungi/oct2003.html) Trichia spp. sporangia

16. Dictyosteliumdiscoideum, a cellular slime mold Contrast to Fig. 2.2 in BK

17. Dictyostelium amoeba aggregate to form a slug that thendifferentiate into a single stalked sporangium or sorocarp

18. Dictyostelium aggregation / differentiation stages in sorocarp formation

19. The biochemistry and molecular biology of Dictyostelium aggregation and sporulation has been extensively investigated. From:Schaap, P. 2011. Evolutionary crossroads in developmental biology: Dictyostelliumdiscoidium. Development 138: 387-396

20. Plasmodiophorabrassicae,clubroot of crucifers. Clubbed root Spores filling cell remnants Plasmodiophora is a genus in the Phytomyxea of the ProtistRhizaria super group. P. brassicae infects over 300 varieties of crucifers world-wide. It’s an obligate, holocarpic (the whole plasmodium differentiates into spores), endoparasite. Infections cause host cell hypertrophy with loss of tissue integrity and function; above ground wilting and yield loss results.

21. Plasmodiophora brassica detailed illustrations

22. Credits @ Designates slides wholly or partially stolen from various PowerPoint presentations created by Dr. Lori Carris for General Mycology 421/521, 2009, Plant Pathology, Dept. WSU.