Uredospores, septa of Basidiomycetes), spirals, reticulations, rings, &c. (capillitium fibres of Podaxon, Calostoma, Battarrea), occur as in the vessels of higher plants, while sculptured networks, pittings and so forth are as common on fungus-spores as they are on pollen grains.
(After Sachs.) C, Mass of uredospores (ur), with one teleutospore (t).
When the sporidia infect a plant the mycelium so produced gives origin to aecidiospores and spermatia; the aecidiospores on infection produce a mycelium which bears uredospores and later teleutospores.
This is the lifehistory of the most complicated forms, of the so-called eu forms. In the opsis forms the uredospores are absent, the mycelium from the aecidiospores producing directly the teleutospores.
In brachy and hemi the aecidiospores are absent, the mycelium from the sporidia giving origin directly to the uredospores; the former possess spermatia, in the latter they are absent.
In lepto and micro forms both aecidiospores and uredospores are absent, the sporidia producing a mycelium which gives rise directly to teleutospores; in the lepto forms the teleutospores can germinate directly, in the micro forms only after a period of rest.
Host on which the uredospores (if present) and the teleutospores are developed.
Uredospores in the hemi and a, Fertile cells; at a 2 the brachy forms, and before the passage of a nucleus from formation of teleutospores in the adjoining cell is seen.
(After Blackman.) uredospores _ l ?
Just as the uredospores and aecidiospores both show these specialized characters in the case of Puccinia graminis so we find that both the conidia and ascospores of E.
These coloured spots are due to the presence of a sorus or layer of countless numbers of minute brown spores, the uredospores of the summer fruiting form.
Towards the end of the summer the uredospores are replaced by the winter resting-spores, called teleutospores, which are larger, thicker-walled and darker in colour.
Infection of the leaves of the young wheat plants follows on the scattering of the aecidiospores: a sorus of the rusty uredospores is produced, and the life-cycle is complete.
(After Sachs.) C, Mass of uredospores (ur) with one teleutospore (t).
(After De Bary.) uredospores probably survive the winter in Europe as well as in Australia and give rise to the rust of the following year.