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Cryptosporella Suffusa
''Cryptosporella suffusa'' is a species of fungus that causes canker A plant canker is a small area of dead tissue, which grows slowly, often over years. Some cankers are of only minor consequence, but others are ultimately lethal and therefore can have major economic implications for agriculture and horticultur ... in alder trees. In 2003 in Alaska, many individual thinleaf alder trees (''Alnus incana'' subsp. ''tenuifolia'') were observed to be dying back, with hundreds or thousands of acres of riparian woodland being affected. Individual trunks and whole clumps were involved, dying within two weeks of the onset of the disease. The cause was found to be the fungus ''Cryptosporella suffusa'', which may also have been responsible for a similar mass mortality of alders in the area in the 1950s. The affected trees seemed to be those suffering from stress, perhaps brought on by drought or resulting from defoliating insects such as the woolly alder sawfly. References {{Tax ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can reproduction, produce Fertility, fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canker
A plant canker is a small area of dead tissue, which grows slowly, often over years. Some cankers are of only minor consequence, but others are ultimately lethal and therefore can have major economic implications for agriculture and horticulture. Their causes include a wide range of organisms as fungi, bacteria, mycoplasmas and viruses. The majority of canker-causing organisms are bound to a unique host species or genus, but a few will attack other plants. Weather and animals can spread canker, thereby endangering areas that have only slight amount of canker. Although fungicides or bactericides can treat some cankers, often the only available treatment is to destroy the infected plant to contain the disease. Examples * Apple canker, caused by the fungus '' Neonectria galligena'' * Ash bacterial canker, now understood to be caused by the bacterium ''Pseudomonas savastanoi'', rather than '' Pseudomonas syringae''. After DNA-relatedness studies ''Pseudomonas savastanoi'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alder
Alders are trees comprising the genus ''Alnus'' in the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few species extending into Central America, as well as the northern and southern Andes. Description With a few exceptions, alders are deciduous, and the leaves are alternate, simple, and serrated. The flowers are catkins with elongate male catkins on the same plant as shorter female catkins, often before leaves appear; they are mainly wind-pollinated, but also visited by bees to a small extent. These trees differ from the birches (''Betula'', another genus in the family) in that the female catkins are woody and do not disintegrate at maturity, opening to release the seeds in a similar manner to many conifer cones. The largest species are red alder (''A. rubra'') on the west coast of North America, and black alder (''A. glutinosa''), nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alnus Incana
''Alnus incana'', the grey alder or speckled alder, is a species of multi-stemmed, shrubby tree in the birch family, with a wide range across the cooler parts of the Northern Hemisphere. Tolerant of wetter soils, it can slowly spread with runners and is a common sight in swamps and wetlands. It is easily distinguished by its small cones, speckled bark and broad leaves. Description It is a small- to medium-sized tree tall with smooth grey bark even in old age, its life span being a maximum of 60 to 100 years. The leaves are matte green, ovoid, long and broad. The flowers are catkins, appearing early in spring before the leaves emerge, the male catkins pendulous and long, the female catkins long and one cm broad when mature in late autumn. The seeds are small, long, and light brown with a narrow encircling wing. The grey alder has a shallow root system, and is marked not only by vigorous production of stump suckers, but also by root suckers, especially in the northern part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eriocampa Ovata
''Eriocampa ovata'', known generally as the alder sawfly or woolly alder sawfly, is a species of common sawfly in the family Tenthredinidae. The larvae feed on the leaves of the common alder (''Alnus glutinosa'') and the grey alder (''Alnus incana''), sometimes causing defoliation. Description The adult female is about long and mainly black, with the exception of the first two segments of the thorax, which are red, and the underside of the tips of the antennae, the inner side of the fore-tibia and the basal part of the hind femur, which are whitish. The head has numerous large puncture marks while the thorax has scattered smaller ones; the abdomen has faint transverse sculpturings. The wings are translucent with black veins. Adult males are unknown in North America, and rare in Europe, the females breeding by parthenogenesis. The larvae grow to a length of . They are white, apart from a brown mark on the head, and are covered with a glossy, white woolly secretion produced b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
