Puccinia cnici
Puccinia cnici | ||||||||||||
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![]() Puccinia cnici |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Puccinia cnici | ||||||||||||
Martius |
Puccinia cnici is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of various thistles . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It iswidespread in the Holarctic .
features
Macroscopic features
Puccinia cnici can only be recognized with the naked eye by means of 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 Puccinia cnici grows as with all Puccinia TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Their spermogonia grow predominantly on the upper side of the host leaves. The aecia of the species, growing on both or mostly underside of the leaves, are surrounded by curly hyphae . Their cinnamon to golden brown aeciospores are 25–33 × 21–30 µm in size, spherical to broadly ellipsoidal and warty. The uredia of the mushroom, which grow on both sides, are chocolate brown. Their dark cinnamon-brown uredospores are 28–38 × 24–28 µm in size, broadly ellipsoidal to ovate and spiky. The parts of the species that grow on both or mainly underside of the leaves are chocolate brown, powdery and uncovered. The chestnut-brown teliospores are two-celled, usually ellipsoidal, wrinkled and usually 35–47 × 21–26 µm in size. Their stem is colorless.
distribution
The well-known distribution area of Puccinia cnici extends from the northern USA via Canada and Russia to Europe .
ecology
The host plants of Puccinia cnici are common thistle and other species of the genus Cirsium . Two varieties are known in Austria: Puccinia cnici var. Cnici occurs on the common scraper, whereas Puccinia cnici var. Crassiuscula occurs on the woolen scrub thistle . 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
- ↑ Peter Zwetko: The rust mushrooms Austria. Supplement and host-parasite directory to the 2nd edition of the Catalogus Florae Austriae, III. Part, Book 1: Uredinales. P. 26. online (PDF; 1.8 MB)