Uromyces holci
| Uromyces holci | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Uromyces holci | ||||||||||||
| Jørstad |
Uromyces Holci is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of the sweet grasses Holcus setiger and Schismus scaberrimus . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. She is endemic to South Africa .
features
Macroscopic features
Uromyces holci can only be recognized with the naked eye by means of the spore beds protruding on the surface of the host. They grow in nests that appear as yellowish to brown spots and pustules on the leaf surfaces.
Microscopic features
The mycelium of Uromyces Holci grows as with all Uromyces TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. The spermogonia and aecia of the species are not known. The orange-yellow uredia of the fungus grow on the upper side of the host leaves. Its pale yellowish uredospores are 22–26 × 20–23 µm in size, mostly broadly ovate to broadly ellipsoidal and spiky. The bilateral growing parts of the species are blackish and loosely covered. The golden to chestnut-brown teliospores are unicellular, usually ovoid and 20-25 × 17-21 µm in size. Their stem is up to 60 µm long.
distribution
The known distribution area of Uromyces holci only includes South Africa .
ecology
The host plants of Uromyces holci are Holcus setiger and Schismus scaberrimus . The fungus feeds on the nutrients present in the storage tissue of the plants, its spore beds later break through the leaf surface and release spores. The species goes through a development cycle of which only Telien and Uredien and their host are known; Spermogonia and Aecien could not be assigned to her.
literature
- George Baker Cummins: The Rust Fungi of Cereals, Grasses and Bamboos . Springer, Berlin 1971, ISBN 3-540-05336-0 .