Uromyces occidentalis
| Uromyces occidentalis | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Uromyces occidentalis | ||||||||||||
| Dietel |
Uromyces occidentalis is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of milkweed and lupins . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It is common in North America.
features
Macroscopic features
Uromyces occidentalis can only be recognized by the naked eye from 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 occidentalis grows as with all Uromyces TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Your spermogonia grow on the underside of the host leaves. The aecia of the species, which also grow on the underside of the leaves, are short and scattered. Their hyaline aeciospores are 19–24 × 15–20 µm in size, spherical to broadly ellipsoidal and warty. The uredia of the fungus growing underneath the leaves are yellow-brown. The yellowish to golden brown uredospores are 22–27 × 18–21 µm in size, spherical to broadly ellipsoidal and spiky. The predominantly leaf underside growing in circles Telien the way are chocolate brown, powdery and uncovered. The teliospores are unicellular, usually ovoid to broadly ellipsoid, warty and usually 19-25 × 16-20 µm in size. Their stem is colorless.
distribution
The known distribution area of Uromyces occidentalis extends from Wyoming to Mexico .
ecology
The host plants of Uromyces occidentalis are for the Haplonten milkweed ( Euphorbia spp.) And various lupins ( Lupinus spp.) For the Dikaryonten . 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 a heterosexual parasite, it changes 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 .