Puccinia mexicensis
| Puccinia mexicensis | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Puccinia mexicensis | ||||||||||||
| Greene & Cummins |
Puccinia mexicensis is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of crested curls and bluegrass . 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
Puccinia mexicensis can only be recognized with the naked eye by means of the spore beds emerging 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 Puccinia mexicensis grows as with all Puccinia TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Aecia or spermogonia of the species are not known. The uredia of the fungus grow on the underside of the host leaves. Its yellowish uredospores are 19–23 × 17–20 µm in size, mostly broadly ellipsoidal to spherical and finely spiky. The parts of the species growing underneath the leaves are blackish, powdery and uncovered early. The hazelnut-brown teliospores are two-celled, club-shaped to long club-shaped and 35–45 × 20–27 µm in size. Their stalk is brownish and 25–40 µm long.
distribution
The known distribution area of Puccinia mexicensis extends from the southern USA to central Mexico .
ecology
The host plants of Puccinia mexicensis are Stipa constricta , S. eminens and S. lettermani . 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 .