Glossary
Term | Definition |
---|---|
amphigynous |
The antheridium is said to be amphigynous when it encircles the oogonial stalk, a condition brought on by the growth of the oogonial initial through the antheridial initial. Compare with paragynous. |
antheridium |
The male gametangium; a multinucleate, swollen hyphal tip affixed firmly to the basal side of the oogonium. |
aplerotic |
Not filled up. Refers to species of the Pythiaceae in which the oospore does not fill the oogonium. Compare with plerotic. |
bleeding |
The oozing of dark reddish-brown droplets of liquid through the bark. |
blight |
A disease characterized by rapid and extensive death of plant foliage. A general term applied to any of a wide range of unrelated plant diseases. (e.g., chestnut blight, fireblight, late blight, halo blight). |
bole |
The trunk of a tree, particularly a large tree with a distinct trunk. |
bullate |
Having bubble- or blister-like swellings |
caducous |
Pertaining to sporangia that become dislodged readily and separate from the sporangiophore (in contrast to being persistent). |
canker |
A plant disease characterized (in woody plants) by the death of cambium tissue and loss and/or malformation of bark, or (in non-woody plants) by the formation of sharply delineated, dry, necrotic, localized lesions on the stem; "canker" may also be used to refer to the lesion itself, particularly in woody plants |
chlamydospore |
An asexual spore, usually globose but occasionally ovoid, that is delimited from the mycelium by a septum; may be terminal or intercalary with a thickened inner wall; survives for long periods in soil. |
clade |
A taxonomic group of organisms classified together on the basis of homologous features traced to a common ancestor. |
clonal lineage |
A population of clonally reproducing individuals that descended from the same ancestor. |
close sympodium |
A simple sympodium in which the sporangiophores are very short. A clustered sympodium has short sporangiophores as well as short nodes between them. |
collar |
The portion of the seedling or plant near the surface of the soil; in grafted woody plants, the scion portion of the plant near the soil surface. |
compound sympodium |
A sympodium with a branched hyphal system from which the sporangiophores initiate, can be irregular or regular. Cf. simple sympodium. |
crown |
The junction of root and stem of a plant, usually at the soil line; in grafted woody plants, the rootstock portion of the plant near the soil surface. |
cyst |
An encysted zoospore, a short-lived resting structure enclosed within a cell wall. |
decline |
Plants are unthrifty and fail to grow, or the canopy may become “thin” due to loss of foliage. This is a gradual process that may take place over a period of several years. |
dieback |
Progressive death of shoots, leaves, or roots, beginning at the tips. |
ellipsoid |
Refers to a solid body that forms an ellipse in the longitudinal plane and a circle in cross section. Many fungal spores are ellipsoidal or elliptic. |
encyst |
To form a cyst or protective covering |
exit pore |
The opening through which zoospores pass when leaving a sporangium; papillate and semipapillate sporangia have exit pores 5 to 7 µm wide; the exit pores of nonpapillate sporangia are about 12 µm wide. |
extended proliferation |
A type of internal proliferation in which the sporangiophore originates inside an empty sporangium, and continues to grow through and out of the old sporangium. |
external proliferation |
External proliferation occurs from growth of a sporangiophore from beneath and external to a sporangium. Cf. extended proliferation. |
flag |
Isolated, wilted or necrotic branch with dead leaves attached. |
flagellum |
Whiplike or tinsel-like appendage of a zoospore that provides locomotion. (Pl. flagella) |
foliar |
Pertaining to leaves. |
fusiform |
Spindle-shaped; tapering at each end. |
globose |
To have a rounded form resembling that of a sphere. |
heterothallic |
Pertaining to sexual reproduction in which mating is possible only through interaction of different mating types. |
homothallic |
Pertaining to sexual reproduction that can take place without the interaction of two different mating types. |
hypha |
Single, tubular filament of a fungal (or oomycete) thallus or mycelium; the basic structural unit of a fungus. (Pl. hyphae) |
hyphal swelling |
Globular swelling that forms at a branch point or within the mycelium. It is by definition (Blackwell 1949) not separated from the coenocytic mycelium by a septum. When separated by a septum and having a thickened inner wall, it is termed a chlamydospore. |
intercalary |
Positioned within a hypha, not terminally. |
internal proliferation |
Internal proliferation occurs when the sporangiophore continues to grow through the empty sporangium. |
lax sympodium |
A sympodium in which the sporangiophores are long and loosely arranged. Compare with close sympodium. |