Puccinia negrensis
| Puccinia negrensis | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Puccinia negrensis | ||||||||||||
| Hennings |
Puccinia negrensis is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of Panicum millet. Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It occurs in Brazil and the Congo .
features
Macroscopic features
Puccinia negrensis 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 negrensis 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 cinnamon-brown uredia of the species grow on both sides of the leaves of the host plants. Their golden to cinnamon - brown uredospores are mostly broad ellipsoid, 24–27 × 17–21 µm in size and finely spiky. The underside growing parts are black-brown, uncovered early and compact. The golden to hazel-brown teliospores are two-celled, generally longitudinally septate, broadly ellipsoidal to spherical and 24–26 × 19–22 µm in size. Their stem is colorless to yellowish and up to 50 µm long.
distribution
The known distribution area of Puccinia negrensis includes the Republic of the Congo and Brazil .
ecology
The host plants of Puccinia negrensis are Panicum millegrana and P. aff. ramosum . 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 .