Puccinia orbicula
| Puccinia orbicula | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Puccinia orbicula | ||||||||||||
| Peck & Clinton |
Puccinia orbicula is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of hare lettuce . Symptoms of the infestation by the species are rust spots and pustules on the leaf surfaces of the host plants. It is common in eastern North America .
features
Macroscopic features
Puccinia orbicula can only be recognized with 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 Puccinia orbicula grows as with all Puccinia TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Your spermogonia grow on both sides of the host leaves. The aecia of the species growing underneath the leaves emerge from the epidermis through pores. Their hyaline aeciospores are 23–30 × 18–22 µm in size, spherical to broadly ellipsoidal and finely waxy. The uredia of the fungus, which usually grow on the underside of the leaves, are light cinnamon brown. The golden to cinnamon-brown uredospores are 25–29 × 23–25 µm in size, spherical to broadly ovate and spiky. The bilateral growing parts of the species are black-brown, powdery and uncovered. The chestnut-brown teliospores are two-celled, usually ellipsoidal to long-ellipsoidal, finely warty and mostly 33–42 × 21–25 µm in size. Their stem is colorless.
distribution
The known distribution area of Puccinia orbicula extends from Newfoundland to Saskatchewan and Virginia .
ecology
The host plants of Puccinia orbicula are various hare lettuce ( Prenanthes spp.). 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 .