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Cypress Canker
Cypress canker is a disease affecting ''Cupressus'' species, caused by one of several species of fungus in the genus ''Seiridium''. Infection causes die-back of twigs and branches in susceptible cypress trees, with rapidly increasing amounts of damage and the death of the tree. History The first epidemic of cypress canker was recorded in California in 1928, with Monterey cypress (''Cupressus macrocarpa'') being affected. Within a few years the local populations of this tree had been killed. The species is widely traded as an ornamental tree and the disease had soon spread worldwide, probably with nursery stock. Within five decades the disease had reached New Zealand, France, Chile, Italy, Argentina, Greece, most of Europe, Canada, North Africa, South Africa and Australia. The causal agent of this pandemic spread was the pathogenic fungus ''Seiridium cardinale'', with '' Seiridium cupressi'' and '' Seiridium unicorne'' sometimes being involved, but being less aggressive; other pat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seiridium
''Lepteutypa'' is a genus of plant pathogens in the family Amphisphaeriaceae. First described by the Austrian mycologist Franz Petrak in 1923, the genus contains 10 species according to a 2008 estimate. The genus ''Lepteutypa'' is teleomorphic (reproducing sexually) and the corresponding anamorphic name, used to describe the asexual form, is ''Seiridium'' (formerly ''Coryneum''). For instance, the name ''Seiridium cupressi'' can still be used for the anamorphic form of that species, but now that it is known that a sexual stage exists, the name ''Lepteutypa cupressi'' should be preferred for the species as a whole. On the other hand, no sexual stage of species ''Seiridium cardinale'' is known, so that is its only name. ''Seiridium cardinale'' and ''L. cupressi'' are important to gardeners and foresters as they cause the devastating Cyprus canker disease of ''Cupressus'', ''Thuja ''Thuja'' ( ) is a genus of coniferous tree or shrub in the Cupressaceae (cypress family). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juniperus Sabina
''Juniperus sabina'', the savin juniper or savin, is a species of juniper native to the mountains of central and southern Europe and western and central Asia, from Spain to eastern Siberia, typically growing at altitudes of .Farjon, A. (2005). ''Monograph of Cupressaceae and Sciadopitys''. Royal Botanic Gardens, Kew. Adams, R. P. (2004). ''Junipers of the World''. Trafford. Description The shrub is very variable in shape, up to tall. The leaves are of two forms, juvenile needle-like leaves long, and adult scale-leaves 1–2 mm long on slender shoots 0.8–1 mm thick. Juvenile leaves are found mainly on seedlings but mature shrubs sometimes continue to bare some juvenile leaves as well as adult, particularly on shaded shoots low in the crown. It is largely dioecious with separate male and female plants, but some individual plants produce both sexes. The cones are berry-like, 5–9 mm in diameter, blue-black with a whitish waxy bloom, and contain 1-3 (rarely 4 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinara Cupressi
''Cinara cupressi'', the cypress aphid, is a brownish soft-bodied aphid. It sucks sap from twigs of conifers, and can cause damage to the tree, ranging from discoloring of the affected twig to the death of the tree. This insect appears to have originated in the Middle East and has been increasing its range and is considered to be an invasive species in Africa and Europe. It has been included in the List of the world's 100 worst invasive species. Taxonomy Several species of aphid have been described on cypresses and related trees in various parts of the world. In North America, these are ''Cinara canadensis'' on ''Juniperus virginiana'', ''Cinara sabinae'' on ''Juniperus sabina'', and ''Cinara cupressi'' on Cupressaceae species in North America. ''C. cupressi'' was also described from Cupressaceae in the United Kingdom. The species ''Lachnus juniperinus'' was described from Poland on ''Juniperus communis'' and ''Thuja occidentalis'', but all these species have since been synonymis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phloeosinus
''Phloeosinus'' is a genus of cedar bark beetles in the family Curculionidae The Curculionidae are a family of weevils, commonly called snout beetles or true weevils. They are one of the largest animal families, with 6,800 genera and 83,000 species described worldwide. They are the sister group to the family Brentidae. T .... There are at least 20 described species in ''Phloeosinus''. Species References Further reading * * * * Scolytinae {{Scolytinae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vector (epidemiology)
In epidemiology, a disease vector is any living agent that carries and transmits an infectious pathogen to another living organism; agents regarded as vectors are organisms, such as parasites or microbes. The first major discovery of a disease vector came from Ronald Ross in 1897, who discovered the malaria pathogen when he dissected a mosquito. Arthropods Arthropods form a major group of pathogen vectors with mosquitoes, flies, sand flies, lice, fleas, ticks, and mites transmitting a huge number of pathogens. Many such vectors are haematophagous, which feed on blood at some or all stages of their lives. When the insects feed on blood, the pathogen enters the blood stream of the host. This can happen in different ways. The ''Anopheles'' mosquito, a vector for malaria, filariasis, and various arthropod-borne-viruses (arboviruses), inserts its delicate mouthpart under the skin and feeds on its host's blood. The parasites the mosquito carries are usually located in its salivary gla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conidium
A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to the way they are generated through the cellular process of mitosis. The two new haploid cells are genetically identical to the haploid parent, and can develop into new organisms if conditions are favorable, and serve in biological dispersal. Asexual reproduction in ascomycetes (the phylum Ascomycota) is by the formation of conidia, which are borne on specialized stalks called conidiophores. The morphology of these specialized conidiophores is often distinctive between species and, before the development of molecular techniques at the end of the 20th century, was widely used for identification of (''e.g.'' ''Metarhizium'') species. The terms microconidia and macroconidia are sometimes used. Conidiogenesis There are two main types of co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resin
In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on naturally occurring resins. Plants secrete resins for their protective benefits in response to injury. The resin protects the plant from insects and pathogens. Resins confound a wide range of herbivores, insects, and pathogens, while the volatile phenolic compounds may attract benefactors such as parasitoids or predators of the herbivores that attack the plant. Composition Most plant resins are composed of terpenes. Specific components are alpha-pinene, beta-pinene, delta-3 carene, and sabinene, the monocyclic terpenes limonene and terpinolene, and smaller amounts of the tricyclic sesquiterpenes, longifolene, caryophyllene, and delta-cadinene. Some resins also contain a high proportion of resin acids. Rosins on the other hand are less ... [...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'' has bee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Host (biology)
In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasite, parasitic, a mutualism (biology), mutualistic, or a commensalism, commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include animals playing host to parasitic worms (e.g. nematodes), cell (biology), cells harbouring pathogenic (disease-causing) viruses, a Fabaceae, bean plant hosting mutualistic (helpful) Rhizobia, nitrogen-fixing bacteria. More specifically in botany, a host plant supplies nutrient, food resources to micropredators, which have an evolutionarily stable strategy, evolutionarily stable relationship with their hosts similar to ectoparasitism. The host range is the collection of hosts that an organism can use as a partner. Symbiosis Symbiosis spans a wide variety of possible relationships between organisms, differing in their permanence and their effects on the two parties. If one of the partners in an ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phloem
Phloem (, ) is the living biological tissue, tissue in vascular plants that transports the soluble organic compounds made during photosynthesis and known as ''photosynthates'', in particular the sugar sucrose, to the rest of the plant. This transport process is called translocation. In trees, the phloem is the innermost layer of the bark (botany), bark, hence the name, derived from the Ancient Greek word (''phloiós''), meaning "bark". The term was introduced by Carl Nägeli in 1858. Structure Phloem tissue consists of conducting Cell (biology), cells, generally called sieve elements, Ground tissue#Parenchyma, parenchyma cells, including both specialized companion cells or albuminous cells and unspecialized cells and supportive cells, such as fibres and sclereids. Conducting cells (sieve elements) Sieve elements are the type of cell that are responsible for transporting sugars throughout the plant. At maturity they lack a Cell nucleus, nucleus and have very few organelles, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thallus
Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms were previously known as the thallophytes, a polyphyletic group of distantly related organisms. An organism or structure resembling a thallus is called thalloid, thallodal, thalliform, thalline, or thallose. A thallus usually names the entire body of a multicellular non-moving organism in which there is no organization of the tissues into organs. Even though thalli do not have organized and distinct parts (leaves, roots, and stems) as do the vascular plants, they may have analogous structures that resemble their vascular "equivalents". The analogous structures have similar function or macroscopic structure, but different microscopic structure; for example, no thallus has vascular tissue. In exceptional cases such as the Lemnoideae, where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mediterranean Climate
A Mediterranean climate (also called a dry summer temperate climate ''Cs'') is a temperate climate sub-type, generally characterized by warm, dry summers and mild, fairly wet winters; these weather conditions are typically experienced in the majority of Mediterranean-climate regions and countries, but remain highly dependent on proximity to the ocean, altitude and geographical location. This climate type's name is in reference to the coastal regions of the Mediterranean Sea within the Mediterranean Basin, where this climate type is most prevalent. The "original" Mediterranean zone is a massive area, its western region beginning with the Iberian Peninsula in southwestern Europe and coastal regions of northern Morocco, extending eastwards across southern Europe, the Balkans, and coastal Northern Africa, before reaching a dead-end at the Levant region's coastline. Mediterranean climate zones are typically located along the western coasts of landmasses, between roughly 30 and 45 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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