Conidial Development in the Fungi Imperfecti - Holoblastic Conidia and Poroconidia
This is a modal window.
The media could not be loaded, either because the server or network failed or because the format is not supported.
Formal Metadata
| Title |
| |
| Alternative Title |
| |
| Author | ||
| Contributors | ||
| License | No Open Access License: German copyright law applies. This film may be used for your own use but it may not be distributed via the internet or passed on to external parties. | |
| Identifiers | 10.3203/IWF/C-1304eng (DOI) | |
| IWF Signature | C 1304 | |
| Publisher | ||
| Release Date | ||
| Language | ||
| Other Version | ||
| Producer | ||
| Production Year | 1977 |
Technical Metadata
| IWF Technical Data | Film, 16 mm, LT, 91 m ; SW, 8 1/2 min |
Content Metadata
| Subject Area | ||
| Genre | ||
| Abstract |
| |
| Keywords | ||
| IWF Classification |
Transcript: English(auto-generated)
00:00
Conidial development in the fungi imperfecti, holoblastic conidia and poorer conidia. In the fungi imperfecti, the different modes of conidiogenesis include two basic types.
00:24
Holoblastic conidia develop de novo from conidiogenous cells by budding. Thallic conidia are formed by the conversion of one or more cells of the pre-existing fertile hyphae. In holoblastic conidial development, the conidium buds de novo from the conidiogenous cell.
00:44
All layers in the wall of the conidiogenous cell take part in forming the wall of the conidia. Holoblastic conidia may arise singly, in clusters or in chains. Conidiogenous cells may terminate growth with the initiation of conidiogenesis, or they
01:02
may elongate after each conidium has formed. A papilla appears at the apex of a determinate fertile cell of Negrospora aridze and increases by swelling to form a solitary holoblastic conidium.
01:30
As the conidium matures, its wall gradually becomes pigmented.
01:47
The conidiogenous cells of nodulosporium hinuleum likewise terminate growth with the initiation of conidiogenesis. After the first terminal conidium has developed, the secondary conidia arise successively and
02:02
precipitally, forming a cluster. Later, new conidia may develop below the apical cluster.
02:28
In Botryosporium longibrachiatum, Botrio's arrangements of holoblastic conidia form synchronously at the apices of the fertile branches of the conidiophore.
02:42
A large number of fertile branches of a conidiophore synchronously undergo conidiogenesis. Several kinds of proliferation are associated with holoblastic conidiogenesis.
03:02
The conidiogenous cell may elongate after the development of each conidium so that the new conidia develop in acropetal succession. The solitary conidia of Trityrhachium aurizae are formed successively by the conidiogenous
03:21
cell. After the first conidium has developed, the mother cell symposially continues growth and at each apex a new conidium develops. The primary holoblastic conidia of Gonatorbotrum apiculatum develop synchronously in a cluster.
03:45
Each primary conidium produces a new conidium at its apex and the process subsequently continues, giving rise to acropetal chains. On the right you see primary conidia developing at the apex of the conidiogenous cell.
04:05
On the left there are chains of secondary conidia being produced. The conidiogenous cell is able to proliferate at its apex.
04:25
In Spegatsinia, the conidiogenous cell proliferates by intercalary growth in the region just below the developed holoblastic conidium, leaving a cup-shaped structure at its base. The proliferate part of the conidiogenous cell and the conidium often sissied together.
04:46
In Spegatsinia thesarthra, the holoblastic conidium arises from the apex of a short mother cell on the vegetative hypha. The conidium becomes septate and pigmented. The conidiogenous cell subsequently elongates from a basal growing region.
05:17
In addition to development of these holoblastic conidia, there is a special mode of conidiogenesis,
05:24
poro-conedial development. There is a visible pore at the base of the conidium and at the conidiogenous cell apex after the conidium has detached. This sketch shows Botrio's poro-conedial development at the fertile apices of a determinate mother cell.
05:42
The first conidium of Eulocladium atrum is formed by the blowing of a restricted region of the conidiogenous cell apex. As the conidium matures, it becomes septate and pigmented.
06:07
The mother cell later proliferates below the base of the first conidium. The mother cell temporarily ceases proliferation and gives rise to the next conidium.
06:33
As shown with the scanning electron microscope, after a conidium of Eulocladium has detached, a pore is visible.
06:43
At the left, a new region of proliferation has already started. A poro-conidium develops at the new apex of a proliferated mother cell on Drexlera sorokiniana. The older conidium has already become pigmented and septate.
07:07
The poro-conidia of Dichotomophthora portulacea are formed synchronously at the apices of short branches of the conidiophore.
07:24
The synchronous conidial development is shown here more clearly.
07:49
As this scanning electron micrograph demonstrates, the poro-conidia of alternaria alternata form characteristic chains.