Exobasidium arescens
| Exobasidium arescens | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Exobasidium arescens | ||||||||||||
| Nannfeldt |
Exobasidium arescens is a mushroom art family of Nacktbasidienverwandten (Exobasidiaceae) from the order Ustilaginomycotina . It is an endoparasite of the bilberry ( Vaccinium myrtillum ) and perhaps also of Vaccinium oreophilum . Symptoms of infestation by the fungus are light-colored spots on the upper surface of the leaves and enlarged leaves of the host plants. The range of the species is in Europe , it may also occur in North America.
features
Macroscopic features
Exobasidium arescens is initially invisible to the naked eye. Symptoms of the infestation are light yellow to reddish spots about 5 mm in size on the upper side of the leaves and in the late stage mycelium protruding on the underside of the leaf .
Microscopic features
The mycelium of Exobasidium arescens grows as with all exobasidium intercellular and forms Saugfäden that grow into the storage tissue of the host. The rarely three-, mostly four-pore basidia are unseptate. They grow directly from the host epidermis or from stomata . The thick, banana-like spores are hyaline and 10–14 × 3–4.5 µm in size. At first they are unicellular, later they have one to three septa . The conidia are 5–10 × 0.8–1.5 µm in size and bacillus to approximately spindle or club-shaped.
distribution
The known distribution area of Exobasidum arescens includes Europe, its occurrence in North America is not certain.
ecology
The host plant of Exobasidium arescens is the bilberry ( Vaccinium myrtillum ) and possibly also Vaccinium oreophilum . The fungus feeds on the nutrients present in the storage tissue of the plants, its basidia later break through the leaf surface and release spores. The spores germinate into conidia, from which new mycelium then develops. The species occurs from planar to montane layers.
swell
- John Frithiof Nannfeldt: Exobasidium, a taxonomic reassessment applied to the European species . In: Symbolae Botanicae Upsalienses . tape 23 (2) , 1981, pp. 1-71 .