Puccinia borealis is a stand fungal art from the order of the rust fungi (Pucciniales). The fungus is an endoparasite of alpine meadow rue and ostrich grasses . Symptoms of infestation by the species are yellow spots of rust and pustules on the leaf surfaces of the host plants. The distribution area includes Northern Europe to the Alps.
Puccinia borealis 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 or blackish spots and pustules on the leaf surfaces.
The mycelium of Puccinia borealis grows as with all Puccinia TYPES intercellular and forms Saugfäden that grow into the storage tissue of the host. Pyknia does not appear to be present. The aecia of the species grow on the underside of the leaves in small groups on reddish spots. They have finely dotted aecidiospores 13 µm in diameter. The uredia grow in oblong, orange piles on pale spots. Their uredospores are 21–30 × 18–23 µm in size, orange and spiky. The parts of the species grow in elongated piles and are black. The teleutospores are two-celled, variably shaped and 26–47 × 12–20 µm in size. They are brown, their stem is short. The basidia and basidiospores are orange.
Puccinia borealis has a distribution area that extends over northern Europe and the Alps .
The host plants of Puccinia borealis are as Haplont alpine meadow rue ( Thalictrum alpinum ) and ostrich grasses ( Agrostris spp.) For the dikaryote . 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 with Uredien, Telien and Aecidien.
- Ernst Gäumann: The rust fungi of Central Europe. With special consideration of Switzerland . In: Contributions to the cryptogam flora in Switzerland . tape XII . Commission publisher Buchdruckerei Büchler & Co, Bern 1959.