Uropyxis holwayi
| Uropyxis holwayi | ||||||||||||
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| Scientific name | ||||||||||||
| Uropyxis holwayi | ||||||||||||
| ( Arthur ) Arthur |
Uropyxis holwayi is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of the legume genera Diphysa and Eisenhardtia . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It is common in southern North America .
features
Macroscopic features
Uropyxis holwayi 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 Uropyxis holwayi grows as with all Uropyxis TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Their spermogonia grow in large numbers on the upper surfaces of the host leaves. The aecia of the species are not known. The same applies to the uredia of the mushroom, it may not develop any. The parts of the species, which usually grow around the spermogonia on the upper side of the leaves, are black to cinnamon-brown, powdery, confluent and uncovered early. The chestnut-brown teliospores are two-celled and double-walled, usually ellipsoidal to long-ellipsoidal and mostly 46–56 × 28–34 µm in size. Its stalk is colorless and swollen apically 30–60 µm thick and 40–60 µm long.
distribution
The known distribution area of Uropyxis holwayi includes Arizona and Guatemala .
ecology
The host plants of Uropyxis holwayi are Diphysa floribunda and various Eisenhardtia species. 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 microcyclic development cycle with spermogonia, aecia and telia. 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 .