Exobasidium cassandrae
| Exobasidium cassandrae | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Exobasidium cassandrae | ||||||||||||
| Peck |
Exobasidium cassandrae is a mushroom art family of Nacktbasidienverwandten (Exobasidiaceae) from the order Ustilaginomycotina . It is an endoparasite of the peat turf ( Chamaedaphne calyculata ). Symptoms of infection by the fungus are galls and spots of red color on the leaves of the host plants. The range of the species is in the northern Holarctic .
features
Macroscopic features
Exobasidium cassandrae is initially invisible to the naked eye. Symptoms of the infestation are reddish, about 5–10 mm large or galls or thickened spots on the upper surface of the leaves and, in the late stages, mycelium protruding on the lower surface of the leaf .
Microscopic features
The mycelium of Exobasidium cassandrae grows as with all exobasidium intercellular and forms Saugfäden that grow into the storage tissue of the host. The four-pore basidia are unseptate. They grow directly from the host epidermis or from stomata . The thick, banana-like spores are hyaline and 12–15 × 3–4 µm in size. The conidia are 6–10 × 2–2.5 µm in size and ellipsoidal to club-shaped.
distribution
The known distribution area of Exobasidum cassandrae covers the northern regions of the Holarctic from Europe to North America.
ecology
The host plant of Exobasidium cassandrae is the peat turf ( Chamaedaphne calyculata ). 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.
swell
- John Frithiof Nannfeldt: Exobasidium, a taxonomic reassessment applied to the European species . In: Symbolae Botanicae Upsalienses . tape 23 (2) , 1981, pp. 1-71 .