Uromyces major
| Uromyces major | ||||||||||||
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| Scientific name | ||||||||||||
| Uromyces major | ||||||||||||
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Uromyces major is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of the sweet grass Muehlenbergia reverchonii . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It occurs in southern North America .
features
Macroscopic features
Uromyces major 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 major growing 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-brown uredia of the fungus grow on both sides of the host leaves. Its cinnamon-brown uredospores are 23–26 × 21–23 µm in size, mostly ovate to broadly ellipsoidal and spiky. The bilateral growing parts of the species are blackish, powdery and exposed early. The chestnut-brown teliospores are unicellular, usually spherical to broadly ellipsoid and 23–28 × 22–26 µm in size. Their stalk is yellowish and up to 75 µm long.
distribution
The known distribution area of Uromyces major includes central Mexico and the US-American Texas .
ecology
The host plant of Uromyces major is Muehlenbergia reverchonii . 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 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 .