Glossary:

achlorophyllous: Lacking chlorophyll; plants which do not have chlorophyll and must find a secondary source of carbon.

anamorph: The asexual reproductive manifestation of a fungus: usually conidial, but may also be sclerotial.

apothecia: The cup or saucer-like fruit body of Ascomycete fungi.

appressorium: A swelling on a germ tube or hypha involved in attachment of the hypha to the root surface.

arbusculate coil: Coil of fungal hypha with fine lateral branches; typical of Paris-type arbuscular mycorrhizas.

arbuscule: A finely branched hypha forming a tree-like structure within a root cortical cell.

arthroconidia: Asexual spores of fungi formed by the segmentation of existing hyphae.

asci: The meiosporangia of Ascomycete fungi usually containing eight ascospores.

ascocarp: The fruiting body of Ascomycete fungi, containing asci, each of which usually contains eight ascospores.

ascospores: Spores contained within the asci of Ascomycete fungi.

autotrophic: Able to manufacture organic compounds from inorganic compounds in the environment.

auxiliary cells (vesicles; bodies): Spore-like structures formed in the extraradical mycelium in species of the arbuscular mycorrhiza genera Gigaspora and Scutellospora.

axenic culture: The growth and maintenance of a single species in isolation, free from foreign or contaminating species.

basidiocarp: A fungal reproductive structure found in the Basidiomycetes involved in producing basidiospores.

basidiospores: Spores which develop on the fruitbody (basidium) of Basidiomycete fungi.

biotroph: A fungus that needs to gain nutrients from living cells.

calcium oxalate crystals: Many fungi, including ectomycorrhizal fungi, exhibit calcium oxalate crystals on their hyphae as a metabolic byproduct. These crystals are thought to inhibit competitive organisms in the soil.

chlamydospore: An asexual spore.

cluster roots: Roots with dense clusters of lateral roots of limited growth; found primarily in the Proteaceae.

conidia: Asexual spores that may be a fungus' main (or substantive) reproductive route.

coralloid clusters: Short, multibranched roots formed during colonization by ectomycorrhizal fungi.

cystidia: Sterile hyphae, often with distinctive shapes, emanating from the suface of the mantle of some ectomycorrhizas, arbutoid mycorrhizas, and monotropoid mycorrhizas.

dematiaceous hyphae: Pigmented hyphae, usually with melanin in the cell walls.

depletion zone: The region around a root from which nutrients such as phosphorus have been absorbed.

dichotomous branching: (See dichotomy)

dichotomy: Root tip which has divided symmetrically into two equivalent root tips.

dolipore septum: A septum (or cross-wall dividing two fungal cells) characteristic of basidiomycete hyphae which flares out in the central portion to form a barrel-shaped structure.

dust seeds: Minute seeds of the orchidaceae comprising 100-200 cells with few storage reserves.

E-strain fungi: Operculate Discomycete fungi, for example, in the genus Wilcoxina, which form ectendomycorrhizas.

endodermis: The inner layer of root cortical cells which develop Casparian bands.

endophyte: An organism that colonizes plant tissues without causing any apparent injury.

entry point: In arbuscular mycorrhizas, a site along the root axis at which an hypha enters.

epigeous: Occurring on the surface of the ground.

exodermis: The outer layer of root cortical cells that develop Casparian bands, usually followed by suberin lamellae deposition.

extraradical hyphae: Vegetative mycorrhiza hyphae growing outside of the root into the soil microenvironment.

extraradical mycelium: Fungal hyphae that emanate from the surface of a mycorrhiza and grow into the substrate.

form-genus: An artificial taxonomic category of organisms for which the true relationships are obscure.

fruit-body: A general term for reproductive structure of many fungi.

fungal peg: A specialized hypha surrounded by finger-like projections of host cell wall within an epidermal cell in monotropoid mycorrhizas presumably for bi-directional transfer of nutrients.

germ tube: A hypha growing from a fungal spore.

glomalin: A glycoprotein produced by arbuscular mycorrhiza hyphae that has a role in soil aggregation.

glycogen: A polysaccharide stored in fungal cells.

hair roots: Very fine roots found in the families Ericaceae and Epacridaceae that have simple anatomy and become colonized by ericoid fungi.

Hartig net: Fungal hyphae that grow between epidermal and cortical cells in ectomycorrhizas.

heterotrophic: Unable to manufacture organic compounds from inorganic compounds.

hyaline: Lacking pigment.

hyphal bridge: A hyphal link (anastomosis) between two hyphal elements; it maintains protoplasmic continuity within the mycelial system and provides the avenue for nuclear exchange and genetic variation.

hyphal coil: A hypha that forms a loop within a root cell.

hyphal complex: A coiled, highly branched hypha found within a host cell.

hypogeous: Occurring under the surface of the ground.

inoculum: Viable fungal propagules that are capable of colonizing new plants.

intracellular: Inside a cell.

intracellular hyphae: Fungal hyphae growing within a plant cell.

intraradical: Inside the root.

mantle: A sheath of fungal hyphae enclosing a root; found in ectomycorrhizas, ectendomycorrhizas, arbutoid mycorrhizas, and monotropoid mycorrhizas.

medulla: The inner fungal tissue, or cortex, of a fungal sclerotium.

melanized: Darkened or pigmented fungal tissue due to deposition of melanin.

microsclerotium: An aggregation of hyphae that contain storage materials and are found within epidermal or cortical cells.

morphotype: A morphologically distinctive type of ectomycorrhiza.

mycelial fans: Mass of vegetative fungal hyphae radiating outwards into the soil or culture medium.

mycobiont: The fungal partner in a mutualistic (mycorrhizal) relationship between a plant and fungus.

myco-heterotrophic plants: Non-photosynthetic plants that depend on links with fungi for their source of carbon compounds from photosynthetic plants.

para-epidermal Hartig net: Morphogically modified fungal hyphae in intimate contact with the outer tangential walls and radial walls of root epidermal cells.

paradermal: A section or view which runs tangentially along the axis of the root epidermis.

peloton: Specialized hyphal complex in orchid host cells.

periarbuscular membrane: Host-derived plasma membrane that surrounds branches of an arbuscule.

peridium/rind: The melanized outermost tissue layer of a fungal sclerotium or a hypogeous fruit body.

perifungal membrane: Host-derived plasma membrane that surrounds fungal hyphae within a plant cell.

polyphosphate: A storage form of phosphate found in fungal vacuoles.

protocorm: In orchids, the stage between embryo and seedling.

rhizoid: An epidermal outgrowth in lower plants involved in nutrient acquisition.

rhizomorph: A linear aggregation of hyphae emanating from the surface of the mantle of many mycorrhizas.

rhizosphere: The region immediately surrounding roots.

saprotroph (saprobe): An organism that gains nutrients from non-living organic matter.

sclerophyllous: A type of vegetation which has hard leaves and short internodes (the distance between leaves along the stem). The word comes from the Greek sclero (hard) and phyllon (leaf). Sclerophyllous plants occur in all parts of the world but are very common in Australia.

sclerotium: A mass of hyphae that originate in the extraradical mycelium of an ectomycorrhiza. Hyphae are organized into a rounded structure covered by melanized hyphae (the rind) enclosing hyphae with various storage compounds.

septum (pl. septa): Crosswall between two contiguous fungal cells.

short roots: Lateral roots which arise from primary tap roots. Often called "feeder" roots, they are the main site of mineral and nutrient exchange between the roots, soil, and mycorrhizal fungi.

simple septum: A septum, or thin crosswall, which develops as an ingrowing ring from the lateral wall of a fungal hypha.

teleomorph: The sexual reproductive form of a fungus.

transfer cell: Parenchyma cell that becomes modified by the formation of ingrowths of primary cell wall enveloped by plasma membrane; found in root cells adjacent to Hartig net hyphae in some ectomycorrhizas.

transformed root: A root in which Ri T-DNA from Agrobacterium rhizogenes has been inserted into its cells causing proliferation of lateral roots.

tripartite: A three way relationship, for example between a plant host, a mycorrhizal fungus, and a bacteria such as Rhizobium.

tubercle: Cluster of ectomycorrhizas enclosed in a sheath (peridium) of hyphae.

uniserate: A single layer (usually of intercellular hyphae in the Hartig net or fungal mantle).

velamen: A multilayered structure (multiple epidermis) of dead cells with special thickenings in the walls, outside the exodermis in older orchid roots.

vesicle: A lipid-filled enlarged portion of a hypha that may develop a thickened wall found in arbuscular mycorrhizas.

vessel hyphae: Hyphae of large diameter located within rhizomorphs; involved with transport of water and mineral ions.

Woronin bodies: Spherical cytoplasmic organelles that can be observed on one or both sides of each septum in Ascomycete fungi. They function as a safety plug, blocking the septal pore to prevent cytoplasm loss in the event of mechanical damage to the mycelium.

Abbreviations:

CM - Confocal microscopy

LM - Light microscopy

FM - Fluorescence microscopy

SEM - Scanning electron microscopy

TEM - Transmission electron microscopy