Uromyces pressus
| Uromyces pressus | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Uromyces pressus | ||||||||||||
| Arthur & Holw. |
Uromyces pressus is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of the daisy family Vernonia deppeana . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It is common in Central America .
features
Macroscopic features
Uromyces pressus can only be recognized with the naked eye by 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 pressus grows as with all Uromyces TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Their spermogonia grow on the underside in small groups on the surface of the host leaves. The aecia of the species, mostly growing underneath the leaves, are light yellow-brown. Their golden to yellowish aeciospores are 26–29 × 23–26 µm in size, broadly ovate to broadly ellipsoidal and warty. The uredia of the fungus, which mainly grow on the underside of the leaves, are light yellow-brown. The yellowish to golden uredospores are 18–21 × 18–22 µm in size, broadly ovate to broadly ellipsoidal and spiky. The predominantly underside of the leaf growing parts of the species are whitish, compact and uncovered. The colorless teliospores are unicellular, usually ellipsoidal to long-ellipsoidal, smooth and mostly 30–37 × 16–19 µm in size. Their stem is colorless and up to 30 µm long.
distribution
The known distribution area of Uromyces pressus includes Guatemala and Costa Rica .
ecology
The host plant of Uromyces pressus is Vernonia deppeana and possible other species of Vernonia . 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 macrocyclical development cycle with Spermogonia, Aecien, Telien and Uredien. As an auto-ecologic parasite, it does not change host .
literature
- George Baker Cummins : Rust Fungi on Legumes and Composites in North America . University of Arizona Press, Tucson 1978, ISBN 0-8165-0653-1 .
Individual evidence
- ^ DF Farr, AY Rossman: Uromyces pressus. (No longer available online.) In: Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Archived from the original on March 4, 2016 ; Retrieved May 17, 2013 . Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
