Uromyces tragi
| Uromyces tragi | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Uromyces tragi | ||||||||||||
| Wakefield & Hansford |
Uromyces tragi is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of the sweet grass tragus berteroanus . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It is common in sub- Saharan Africa.
features
Macroscopic features
Uromyces tragi 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 tragi grows as with all Uromyces TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Aecia or spermogonia of the species are not known. The cinnamon to yellow-brown uredia of the fungus grow on both sides or predominantly on top of the host leaves. Its golden to cinnamon-brown uredospores are 23–27 × 19–22 µm in size, mostly ellipsoidal to broadly ellipsoidal and spiky. The bilateral growing parts of the species are blackish and covered or arise from old uredia, they have no paraphyses. The chestnut-brown teliospores are unicellular, usually angular ovoid to oval and 23–30 × 17–22 µm in size. Their stem is colorless and up to 25 µm long.
distribution
The known distribution area of Uromyces tragi extends from Kenya and Uganda to South Africa .
ecology
The host plant of Uromyces tragi is Tragus berteroanus . 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 has a development cycle of which only Telien and Uredien and their host are known; Spermogonia and aecia could not be assigned to the fungus.
literature
- George Baker Cummins: The Rust Fungi of Cereals, Grasses and Bamboos . Springer, Berlin 1971, ISBN 3-540-05336-0 .