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abaxial: the upper surface of a leaf or needle.
acute: pointed, sharp-edged, less than a right angle.
acyanophilous (cf. cyanophilous): not readily absorbing a blue stain such as cotton blue or gentian violet.
advanced decay: advanced destruction of plant or animal matter by fungi or other micro-organisms. Wood tissue is generally soft.
aeciospore: binucleate asexual spores of rust fungi formed as a result of the sexual fusion of cells but not of the nuclei.
aecium (pl. -ia): site of production of aeciospores in the rust fungi.
alternate host: one or the other of the two unlike hosts of a heteroecious rust fungus.
amphigenous: growing all around or on both sides of a leaf or needle.
amyloid: spores and hyphae are designated as amyloid if they turn grey or blue-black upon treatment with Melzer's Iodine reagent (see dextrinoid, IKI-).
annual: a plant that completes its life cycle within 1 year and then dies.
annulus: the ring of tissue left on the stalk (stipe) of a mushroom when the partial veil (pileus) breaks.
apiculus: a short projection at one end of a spore.
apothecium (pl. -ca): the cup or saucer-shaped fruiting body of the Ascomycotina.
arthroconidium (pl. -ia): an asexual spore produced from the division a hypha into separate cells.
aseptate: without crosswalls, generally referring to fungal hyphae.
ascus (pl. -ci): a sac-like cell of an Ascomycete within which two haploid nuclei fuse, after which three divisions occur, two of them meiotic, resulting in eight ascospores.
ascospore: a sexually generated propagative unit of the Ascomycotina, a spore produced within an ascus.
ascostroma (pl. -mata): a stroma containing asci.
asexual stage (cf. sexual stage): that part of a life cycle where reproduction does not involve the fusion of gametes and meiosis.
bacillar: rod-like in form.
basidiospore: a propagative cell of the Basidiomycotina containing one or two haploid nuclei produced, after meiosis, on a basidium.
bilabiate: from the Latin two-lipped, describing a dehiscence mechanism in bitunicate asci where the tip of the ascus splits to form two lips
biseriate: arranged in or having two series or rows.
bitunicate: having two walls, as in the asci of Loculoascomycetes.
callus: wound tissue, composed of soft parenchymatous tissue formed on or about injured surfaces of stems and roots.
cambium: a persistent layer of generative, meristematic cells that gives rise to secondary wood (xylem) and secondary inner bark (phloem).
canker: a disease of woody plants characterized by sharply delimited necrosis of the cortical tissues and malformation of the bark caused by recurring localized killing of the cambium layer.
caulicolous: living on herbaceous stems.
chlamydospore: an asexual spore (primarily for survival, not dissemination) formed by modification of a hyphal segment.
chlorosis (adj. chlorotic): an unseasonable yellowing of the foliage, symptomatic of a chlorophyll deficiency in the leaf tissues.
circumscissile: opening or cracking along a circle.
clamp connection (also clamp): a bridge-like hyphal connection characteristic of the secondary mycelium of many Basidiomycetes.
clavate: club-like, narrowed at the base.
clypeus: a shield-like growth over a perithecium.
concolorous: of one colour
conidium (pl. -ia): an asexual fungal spore.
conidiophores: a specialized hypha from which conidia are produced.
conk: a fruiting body of a wood-destroying fungus.
context: the inner or body tissue of a fruiting body that supports the fruiting surface.
cyanophilous (cf. acyanophilous): readily absorbing a blue stain such as cotton blue or gentian violet.
cystidium (pl. -ia): a sterile structure, frequently of distinctive shape, generally occurring on the hymenial surface of a basidiomycete fruiting body.
daedaloid: pores that are irregularly lobed and sinuous in outline, labyrinthiform.
dextrinoid: spores and hyphae are designated as dextrinoid if they turn reddish-brown upon treatment with Melzer's Iodine reagent (see amyloid, IKI-).
dieback: the progressive dying, from the tip downward, of twigs, branches, tops, or roots of plants.
echinulate: covered with slender sharp spines, here referring to spore surface characteristics.
effused-reflexed: spread out over the substratum and turned back at the margin; refers to the growth form of polypore fruiting bodies.
epidemic: a widespread high level of disease incidence beyond normal proportions.
epidermis: a superficial layer of cells occurring on all parts of the primary plant body; stems, leaves, roots, flowers, and seeds.
epiphyllous: growing on the upper, adaxial surface of a leaf or needle.
episporium (also epispore): the thick fundamental layer that determines the shape of the spore.
erumpent: bursting through the bark.
excipulum: tissues of the apothecium; ectal-, forms outermost layers, including the margin, and medullary-, the zone enclosed by the ectal excipulum and the hypothecium.
flag (also flagging): a dying, or recently dead, twig or branch, the foliage of which contrasts in colour with the normal green foliage of living trees.
fruiting body (also sporophore, conk): a structure that bears the spore-producing structures and spores in fleshy and woody higher fungi.
fungus (pl. -gi): one group of the lower plants that lack chlorophyll, thus requiring a host from which to obtain food.
fusoid: almost fusiform.
fusiform: spindle shaped, tapering at both ends.
generative hyphae: the hyphal type present in all basidiocarps, typically thin-walled, with clamps or simple-septate; from them develop the hymenial elements, and in some species, the skeletal and binding hyphae.
geniculate: bent like a knee.
germ pore: a thin circular area in the spore wall through which the germ tube develops.
guttulate: having one or more oil drops inside.
heartwood: the central part of a tree that is no longer active in the transport or storage of water or nutrients.
host: a plant or other organism that furnishes subsistence to, or harbours, a parasite.
hypha (pl. -ae): a fungal thread or filament.
hyaline: transparent, colourless.
hymenium: the spore bearing layer of a fungal fruiting structure.
hyperparasite (adj. -itic): a parasite that is parasitic on another parasite.
hypertrophy: the state of having growth greater than normal.
hypophyllous: growing on the lower, abaxial surface of a leaf or needle.
hypothecium: the hyphal layer under the hymenium of an apothecium.
hysterothecium (pl. -cia): an elongated ascocarp with an longitudinal slit; characteristic of some needle-cast fungi.
IKI-: no colour response when treated with Melzer's Iodine reagent; sometimes referred to as inamyloid (see amyloid, dextrinoid).
incipient decay: an early stage in decay in which the wood may show discoloration but is not otherwise visibly altered. The wood is generally firm and sound.
indeterminate: having the edge not well defined, especially of fruit-bodies and leaf-spots; continuing growth indefinitely.
infection court: the site of invasion of a host by a pathogen.
inoculum: spores or tissue of a pathogen that serve to initiate disease in a plant.
intercalary: between apex and base.
J-: does not stain in iodine; common usage in Ascomycete identification.
laccate: polished, varnished, shining.
laminate: separated into sheets or layers (lamellae).
lenticular: like a double convex lens in form.
lesion: a definite, localized area of dead tissue, a circumscribed diseased area.
locule: a cavity in a stroma.
Melzer's reagent: a solution consisting of 2.5 g iodine, 7.5 g potassium iodide, and 100 g chloral hydrate per 100 mL of water used to detect amyloid and dextrinoid reactions.
monostichous: forming in a line; refers here to the alignment of ascospores in as ascus.
mycelial fan: a fan-shaped mycelial mat forming under the bark of roots and lower stems of trees; often associated with Armillaria root rot.
mycelium: collective term for hyphae or fungus Filaments.
necrosis: death of the affected tissues.
obligate parasite: a parasite that is incapable of existing independently of living tissues.
ostiole: a pore through which spores are freed from a perithecium or pycnidium.
papillate: small, rounded.
paraphyses: sterile structures in a hymenium.
parasite: an organism that draws a part or the whole of its nourishment from another living organism.
parenchyma: tissue composed of more or less isodiametric cells, usually thin-walled with intercellular spaces (cf. pseudoparenchyma).
pathogen: an organism capable of causing disease.
pathogenic: disease-causing or able to be so.
penicillate: like a little brush.
perennial: an organism that lives from year-to-year.
Peridium (pl. -ia): the wall or limiting membrane of a sporangium or other fungal fruiting structure
periderm: the outermost, corky layer of bark of a tree.
peridermioid: more or less like the peridermium.
peridermium (pl. -ia): an aecium with a blister-like, tongue-shaped, or cylindrical peridium.
perithecium: the sub-globose or flask-shaped ascocarp of an Ascomycete fungus.
phloem: food-conducting tissue, consisting of sieve tubes, companion cells, phloem parenchyma, and fibers.
phialide (adj. phialidic): a type of conidiogenous cell that produces conidia through a special opening where neither wall contributes toward formation of the conidium; conidia are produced basipetally with no detectable increase in length.
plectenchyma: fungaL tissue formed by hyphae becoming twisted and fixed together.
pore: an opening on the fertile surface of bolete and polypore fungi, through which basidiospores are disseminated.
pore surface: the surface of polypore or bolete fruiting body bearing pores through with basidiospores are disseminated.
poroid: with pores.
pseudooperculum: characteristic of one of nine structural types of ascus (pseudooperculate).
pseudoparaphyses: sterile hyphal structures connected to both the upper and lower surface of and ascocarp.
pseudoparenchyma: plant tissue composed of more or less isodiametric cells.
punk knot: decayed branch stubs that often indicate the presence of decay in a tree.
pustule: a blister-like, frequently erumpent, spot or spore-mass.
pycnidium: a flask-shaped, asexual fruiting body lined with conidiophores.
resinosis: an abnormal exudation of resin or pitch from conifers.
resupinate: a fruiting body reclined or flat on the substratum.
reverse: refers to the colour of the bottom of a petri plate on which a fungal culture is growing.
rhizomorph: a strand or cord of compact mycelium, often dark coloured; characteristic of Armillaria spp.
rugulose: delicately wrinkled.
semipileate: with a cap that is partially appressed to the substrate.
saprophyte: an organism using dead organic material as food.
septate: possessing a cross-wall forming a division in a spore or hypha.
seta: a stiff hair or bristle.
sexual stage (cf. asexual stage): that part of a life cycle where reproduction involves the fusion of gametes and meiosis.
sign: visible evidence of a disease organism, (e.g., mycelium, fruiting bodies).
skeletal hyphae: thick-walled hyphae, branched or unbranched, aseptate, straight or slightly flexuous with thin-walled apices.
spermatium (pl. -ia): non-motile, uninucleate, spore-like male structure serving as a gamete in sexual reproduction.
spermagonium (pl. -ia): a fruiting structure in which spermatia are produced, sometimes referred to as a pycnium in some rust fungus literature.
spore: the reproductive structure of fungi and other cryptograms, corresponding to a seed in flowering plants.
sporodochium (a): a cushion-shaped conidial fruiting structure in which the spore mass is supported by a stroma covered by short conidiophores.
sporophore: see fruiting body.
sterigma (pl. -ata): a tapering projection on a basidium on which basidiospores develop.
sterile conk: a conk not producing spores or a sporocarp.
stipe: a stalk-like or stem-like structure that supports the pileus of a basidiomycete fruiting body.
stipitate: possessing a stipe.
stroma (pl. -ata): a mass or matrix of vegetative hyphae, with or without tissue of the host or substrate, sometimes sclerotium-like in form, in or on which spores are produced.
subcuticular: underlying the cuticle.
subhypodermal: underlying the hypodermis.
subiculum: a net-like, or crust-like growth of mycelium from which fruiting bodies are formed.
subulate: tapering to a point; awl-shaped.
symptom: the noticeable evidence of change in the physiology or morphology of a host as a result of disease.
systemic: a parasite which spreads throughout the host; a fungicide that is absorbed by the roots and is translocated to other parts of the plant.
telium (pl. -ia): a sorus producing teliospores; refers to rust fungi.
teliospore: a spore (commonly a winter or resting spore) of the rust fungi from which the basidium is produced.
terminal vesicle: the swollen apex of the conidiophore or hypha.
tramal hyphae: the layer of hyphae in the central part of a lamella of an agaric, a spine of Hydnaceae, or the partition between pores in a polyphore.
tuberculate: having tubercles, having small wart-like processes.
tubes: spore-bearing structures in polypores and boletes, aligned vertically and terminating in openings on the pore surface.
uniseriate: arranged in or having one series or row.
urediniospore: a binucleate spore borne in a uredinium and capable of infecting the same host on which it originated, usually echinulate.
uredinium (pl. -ia): a sorus that produces urediniospores, produced after the aecium and after the telium in the life cycle of rust fungi.
verruculose: possessing delicate, small rounded processes or warts.
verticillate: having parts in rings (verticils), whorled.
virulence: degree of pathogenicity of a pathogen, the relative capacity of a pathogen to cause disease.
xylem: a plant tissue consisting of tracheids, vessels, parenchyma cells and fibers; wood.
zone lines: narrow, dark-brown or black lines in decayed wood, generally resulting from the interaction of different strains or species of fungi.