Mycology

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Mycology (菌学)

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

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[fungi, mycorrhiza, saprophytic plant, fungal taxonomy, lichens, references]

myco = fungus (Greek) + logy = logic (Greek)
Formerly, mycology is one of the subjects in botany.

taxonomy
genetics
medicine, pharmacy and pathology
agriculture
ecology

Animals and fungi are sister groups while plants constitute an independent evolutionary lineage.

About 100,000 named species and perhaps more than 200,000 unnamed species

Nutrition: heterotrophic (photosynthesis lacking) and absorptive (ingestion rare). No photosynthetic ability (heterotrophic nutrition)
Mode of life: saprophytic, parasitic, or symbiotic
Thallus: on or in the substratum and plasmodial amoeboid or pseudoplasmodial; or in the substratum and unicellular or filamentous (mycelial), the last, septate or nonseptate; typically nonmotile (with protoplasmic flow through the mycelium) but motile states (e.g., zoospores) may occur.

Cell wall: well-defined, typically chitinished (cellulose in Oomycetes).
Nuclear status: eukaryotic, multinucleate, the mycelium being homo or heterokaryotic, haploid, dikaryotic, or diploid, the last being usually of limited duration.

Reproduction (繁殖): sexuality → asexual or sexual and homo-or heterothallic
Sporocarps (胞子嚢果): micro-or macroscopicc and showing limited tissue differentiation
Habitat (生息地): ubiquitous as saprobes, symbionts, parasites, or hyperparasites
Distribution (分布): cosmopolitan

Fungus, pl. fungi (菌類)

Hypha (菌糸, pl. phyphae)

a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium
→ the main mode of vegetative growth for most fungi

Mycelium (菌糸体, pl. mycelia)

root-like structure of a fungus consisting of a mass of branching, thread-like hyphae

Life cycle

Fig. Fungal life cycles. Each circle represents a life cycle and should be read clockwise; M, meiosis; single line, haploid phase; double line, dikaryotic phase; solid line, diploid phase. The three principal life cycles are as follows; 1, asexual; 2, haploid (common in Ascomycotina); 3, haploid dikaryotic (many Ascomycotina have a brief dikaryotic phase but a long dikaryotic phase is typical of Basidiomycotina); 4, haploid-diploid (unusual in fungi but occurs in some Chytridiomycotina); 5, diploid (characteristic of the Straminipila, only very rarely in Eumycota). (Burnett 1975)

Zygomycete

Ascomycete

Basidiomycete

Reproduction (生殖)

Perfect and imperfect states

Conidium (pl. conidia, 分生子)

Blastic: holoblastic, enteroblastic
Thallic: holothallic, holoarthric, enteroarthric

Morphology (形態)

adnate 沿着の

Fruiting body (子実体)

0) Growth mode

6) Skirt (鍔)

(Left to right) pendant, flaring, sheathing, double, clbwebby, ring zone

8) Spore print (胞子紋)

Diagrams of gill characters, as shown by the lower surface of the pileus

Fairy ring, fairy circle, elf circle or pixie ring (菌輪): occurring ring or arc of mushrooms

tethered type: mycorrhizal fungi living in symbiosis with trees
free type: not connected with other organisms → saprotrophic

Food

High protein (20-30% of dry mass) containing essential amino acids
chitinous walls as a source of dietary fiber
containing B-group vitamins
low in fat
virtually free of cholesterol

Morels 1 Morels 2
[1] Edible and choice Morchella spp. (morels) [2] Do not eat Gyromitra esculenta (left) and Verpa boheica (right). Morels are common in Alaska soon after wildfires (森林火災). (Morchella f<g Gr植物名morchelから。ノボリリョウ科)

Yeast (酵母)

Classification ((Lodder & Kreger-van Riji 1952)

Yeast groupu (family)	Subfamily	Representative genera
Ascosporogenous yeast 有子嚢胞子酵母 (Endomycetaceae)	Schizosaccharomycetoideae Saccharomycetoideae Nematosporoideae	Schizosaccharomyces, Endomycopsis Saccharomyces, Pichia, Debaryomyces, Hansenula, Nadsonia Nematospora, Lipomyces
Sporobolomycetous yeast スポロボロミセス酵母 (Sporobolomycetaceae)		Sporobolomyces, Bullera
Asporogenous yeast 無胞子酵母 (Cryptococcaceae)	Cryptococcoideae Trichosporodideae Rhodotoruloideae	Cryptococcus, Torulopsis, Candida, Trigonopsis Trichosporon Rhodotorula

Ecology (生態)

Succession of fungi (遷移)

Primary and secondary sere

Coprophilous fungi (糞生菌)

Parasitic fungi (寄生菌)

Materials for parasite
Animal: entomogenous, predacious, mycoses
Plant: parasitic fungi

Ex. Peronosporaceae (露菌): obligate parasites on plants
Ex. Taphrinaceae: Taphrina (タフリナ), parasite on angiosperms - semi-parasite
Ex. Hypodermataceae (葉フルイ病菌): Lophodermium, Hypoderma
Ex. Agnomycetaceae (無胞子菌): Rhizoctonia (リゾクトニア)
Ex. Melioaceae: Melioa and many others - sooty mold (スス病)

Fungi (菌生菌/重複寄生菌): fungi that parasitize other fungi

Ex. Tolypocladium capitatum (タンポタケ), (T. ophioglossoides (ハナヤスリタケ), Nyctalis lycoperdoides = Asterophora lycoperdoides (ヤグラタケ)

Phytopathology (植物病理学)

Plant disease: damages (= diseases) due to the disruption of physiological processes

Infectious diseases, derived mostly by pathogenic organism, e.g., fungus, bacterium, mycoplasma, virus, viroid, nematode, or parasitic flowering plant
Noninfectious diseases: unfavourable growth conditions, including temperature, moisture, oxygen, toxic substances in the soil or atmosphere

Bast (disease) or dieback (胴枯病): filamentous fungi (糸状菌)

apple, infected by Diaporthe tanakae and Phomopsis mali

Powdery or white mildew (ウドンコ病)
Erysiphaceae(ウドンコカビ/菌)

Grape: Erysiphe necator or Uncinula necator
Wheat, barley, oat: Blumeria graminis (most Poaceous species are infected by this species)
Peach: Sphaerotheca pannosa
Strawberry: Sphaerotheca humuli
Tomato: Oidium lycopersici
Cucumber: Erysiphe polygoni and Sphaerotheca cucurbitae
Rose: Sphaerotheca pannosa and Uncinula simulans
Mulberry: Phyllactinia moricola

Rust desease (サビ病): by rust fungi (obligate parasite on living plants)
Pucciniales or Uredinales (サビ菌)

Pucciniaceae (柄生サビ菌): Uromyces, Gymnosporangium, Puccinia, Phragmidium
Melampsoraceae (層生サビ菌): Melampsora, Cronartium
Uredinales Imperfecti (不完全サビ菌): Aecidium, Uredo

Generation: spore types (sg. -um)

0: spermogonia (柄子)
I: aecia (サビ胞子)
II: uredinia (夏胞子)
III: telia (冬胞子)
IV: basidia (小生子)
Heterecious (異種寄生性): one species infects two plant hosts in different generations

Violent root-rot (紋羽病): facultative parasites
White root-rot (白紋羽病): Rosellinia necatrix
Violet root-rot (紫紋羽病): Helicobasidium mompa
Crown wart (こぶ病) - bacteria
Soft rot (軟腐病)

Erwinia aroideae, E. carotovora

[mycorrhiza helper bacteria]

Mycorrhiza (菌根菌)

A symbiotic or pathogenic relationship between fungi and the vascular plant roots

Fungus kingdom: Basidiomycetes, Ascomycetes and Zygomycetes

Plants give carbohydrates produced by photothynthesis to fungi

Reward:
increase root surface area
increase ability to capture water, N and P
increase tolerance to adverse soil conditions
provide protection against pathogenic fungi and nematodes
modify composition of rhizosphere

Fungi give nutritents for photothynthesis, in particular, N and P, to plants

Endomycorrhiza (内生菌)

the hyphae penetrating the plant cell wall and invaginate the cell membrane

Arbuscular mycorrhiza (AM, formerly VAM)
colonize most plants
most are nonhost-specific

Glomeromycota

Ericoid mycorrhiza
Arbutoid mycorrhiza
Orchid mycorrhiza
Monotropoid mycorrhiza

Ectomycorrhiza, ECM (外生菌)

the hyphae not penetrating plant cells within the root

limited to trees and shrubs
most are host-specific
Ectendomycorrhiza → in case that the hyphae of ectomycorrhiza penetrate the plant cells

Akasaka, Tsuyuzaki & Hase 2007

Annual growth of invasive Larix kaempferi seedlings with reference to microhabitat and ectomycorrhiza1 colonization on a volcano

Titus JH & Tsuyuzaki S. 2002

Arbuscular mycorrhizal distribution in relation to microsites on recent volcanic substrates of Mt. Koma, Hokkaido, Japan

Fig. 1. Five types of mycorrhizae observed on Mount Koma in 2000. A: arbuscular mycorrhizae detected from the roots of Elaeanus pungens Thunb., B: ectomycorrhizae from the roots of Salix bakko Kimura., C: ericoid mycorrhizae from the roots of Ledum palustre L. var. diversipilosum Nakai, D: orchid mycorrhizae from Spiranthes sinensis (Pers.) Ames, and E: arbutoid mycorrhizae from Pyrola incarnata Fisch. M: mantle, H: hyphae, C: hyphal coil, V: vesicules, and A: arbuscules. OH: outer hyphae. IHC: Intracellular-hyphae-complex. No monotropoid mycorrhizae were observed in the present study. Each scale bar indicates 50 mm. (Tsuyuzaki et al. 2005)

Isotope analysis

Sporocarps of mycorrhizal fungi (Hobbie et al. 2001):

3.5 ‰↓ δ¹³C
5.7 ‰↑ δ¹⁵N
→ δ¹³C should be interpreted cautiously (Hobbie et al. 2002)

Assumptions on N availability and isotopes (Hobbie & Colpaert 2003)

mycorrhizal fungi have higher δ¹⁵N
mycorrhizal plants have lower δ¹⁵N
ectomycorrhial plants have lower δ¹⁵N at low N availability
δ¹⁵N of nonmycorrhizal plants does not change with N availability

Saprophytic plant (腐生植物)

= myco-heterotrophy
symbiotic relationship between plants and fungi, in which the plant gets all or part of its food from parasitism on fungi rather than from photosynthesis
Habitats → forests (with many exceptions)