Scleroderris canker
Encyclopedia
Scleroderris canker or Brunchorstia disease (Europe
an name), Gremmeniella abietina, is a species
of fungal diseases infecting coniferous forests. The main symptom is the death of the needle
s, leading to the death of the tree. In the forest industry, fighting off an infection of Scleroderris canker is usually not cost-effective. Clearing is often preferred over fungicidal
methods, as the latter is harmful to other living organisms.
. The American strain limits itself to north of 44°N
.
There are two strains
of the fungus in existence, the North American and European. The latter is more virulent, capable of infecting an entire tree and killing it over a few years time, whereas the North American strain limits itself to the first few metres of the stem. Another reason behind the high potency of the European strain is that trees are unable to defend themselves from the fungus during winters, as the fungus can remain active at temperatures as low as -5°C
Early signs of a Scleroderris canker infection includes a purple tint in the needles and, more evidently, the falling off the needles in the wrong season. A severe Scleroderris canker infection can sometimes be disastrous, as the fungus survives on the pine cones, killing any new seedlings within two years.
Chances of infection increase greatly if the previous winter has been mild and the spring season is cool and wet, due to the active temperature. Infection occurs in damaged bud
s and proceeds downwards into the stem, and ascospores are released from November to July.
can be used to ward off the disease in nurseries. However, it is ineffective in adult populations.
s. Regulating such imports can limit the spread of the disease.
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an name), Gremmeniella abietina, is a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of fungal diseases infecting coniferous forests. The main symptom is the death of the needle
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
s, leading to the death of the tree. In the forest industry, fighting off an infection of Scleroderris canker is usually not cost-effective. Clearing is often preferred over fungicidal
Fungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality and profit. Fungicides are used both in agriculture and to fight fungal infections in animals...
methods, as the latter is harmful to other living organisms.
Geographical distribution
The European strain is present throughout all of Europe, including the European part of RussiaRussia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
. The American strain limits itself to north of 44°N
Latitude
In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...
.
Cause and symptoms
Strain (biology)
In biology, a strain is a low-level taxonomic rank used in three related ways.-Microbiology and virology:A strain is a genetic variant or subtype of a micro-organism . For example, a "flu strain" is a certain biological form of the influenza or "flu" virus...
of the fungus in existence, the North American and European. The latter is more virulent, capable of infecting an entire tree and killing it over a few years time, whereas the North American strain limits itself to the first few metres of the stem. Another reason behind the high potency of the European strain is that trees are unable to defend themselves from the fungus during winters, as the fungus can remain active at temperatures as low as -5°C
Early signs of a Scleroderris canker infection includes a purple tint in the needles and, more evidently, the falling off the needles in the wrong season. A severe Scleroderris canker infection can sometimes be disastrous, as the fungus survives on the pine cones, killing any new seedlings within two years.
Chances of infection increase greatly if the previous winter has been mild and the spring season is cool and wet, due to the active temperature. Infection occurs in damaged bud
Bud
In botany, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a leaf or at the tip of the stem. Once formed, a bud may remain for some time in a dormant condition, or it may form a shoot immediately. Buds may be specialized to develop flowers or short shoots, or may have...
s and proceeds downwards into the stem, and ascospores are released from November to July.
Chemical
The fungicide ChlorothalonilChlorothalonil
Chlorothalonil is a polychlorinated aromatic mainly used as a broad spectrum, non-systemic fungicide, with other uses as a wood protectant, pesticide, acaricide, and to control mold, mildew, bacteria, algae. Chlorothalonil-containing products are sold under the names Bravo, Echo, and Daconil. It...
can be used to ward off the disease in nurseries. However, it is ineffective in adult populations.
Regulatory
It has been found that the European strain can spread via the import of Christmas treeChristmas tree
The Christmas tree is a decorated evergreen coniferous tree, real or artificial, and a tradition associated with the celebration of Christmas. The tradition of decorating an evergreen tree at Christmas started in Livonia and Germany in the 16th century...
s. Regulating such imports can limit the spread of the disease.
Synonyms
- Lagerbergia abietina (Lagerberg)
- Ascocalyx abietina (Lagerberg)
- Scleroderris abietina (Lagerberg)
- Scleroderris lagerbergii