Rhytisma vaccinii - Ритизма вакциниевая - Blueberry Tar Spot - Heidelbeer-Tarzfleckenpilz 8/14/15—4/23/23
Rhytisma vaccinii is an interesting species of fungi belonging to the family Rhytismataceae within the Ascomycota phylum. This fungus primarily infects plants in the Vaccinium genus, such as blueberries, cranberries, and lingonberries, causing a condition known as tar spot disease. It has been reported in various regions across North America and Europe, particularly in areas where these Vaccinium species are native or cultivated.
The fruiting bodies of Rhytisma vaccinii, called apothecia, appear as dark, tar-like spots on the surface of infected leaves. These spots may be surrounded by a yellowish or reddish halo, giving the infected leaves a distinctive appearance. The fungus overwinters on fallen leaves and releases spores during the following spring, which then infect new leaves.
The asci of Rhytisma vaccinii typically contain eight spores each, a characteristic feature of fungi in the Ascomycota phylum. The spores are elongated and needle-shaped, measuring approximately 40-70 x 1-2 µm, and are hyaline, which makes them almost transparent. They often appear in clusters or fascicles.
Rhytisma vaccinii is considered a plant pathogen, causing tar spot disease in Vaccinium species. While the disease can lead to unsightly leaf spots and potentially reduce photosynthesis, it rarely causes significant harm to the overall health of the plant. However, in some cases, severe infections may result in reduced growth, defoliation, or decreased fruit yield.
As Rhytisma vaccinii is a plant pathogen and not a mushroom-forming fungus, it is not edible. Its primary importance lies in its impact on the health of Vaccinium plants and as a subject of study for plant pathologists, mycologists, and naturalists.
To manage tar spot disease caused by Rhytisma vaccinii, it is recommended to collect and dispose of infected leaves during the fall season, which helps to reduce the source of inoculum and limit the spread of the fungus to new leaves in the following year. Fungicides are generally not recommended, as tar spot disease is usually not severe enough to warrant their use.
Rhytisma vaccinii - Ритизма вакциниевая - Blueberry Tar Spot - Heidelbeer-Tarzfleckenpilz