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Blight
Blight refers to a specific symptom affecting plants in response to infection by a pathogenic organism. Description Blight is a rapid and complete chlorosis, browning, then death of plant tissues such as leaves, branches, twigs, or floral organs. Accordingly, many diseases that primarily exhibit this symptom are called blights. Several notable examples are: * Late blight of potato, caused by the water mold '' Phytophthora infestans'' (Mont.) de Bary, the disease which led to the Great Irish Famine * Southern corn leaf blight, caused by the fungus ''Cochliobolus heterostrophus'' (Drechs.) Drechs, anamorph ''Bipolaris maydis'' (Nisikado & Miyake) Shoemaker, incited a severe loss of corn in the United States in 1970. * Chestnut blight, caused by the fungus ''Cryphonectria parasitica'' (Murrill) Barr, has nearly completely eradicated mature American chestnuts in North America. * Citrus blight, caused by an unknown agent, infects all citrus scions. * Fire blight of pome fruits, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citrus Blight
Citrus blight is a type of blight that occurs in tropical and semi-tropical regions. Specializing in infecting citrus trees, the blight is found in North America, the Caribbean, South America, South Africa and Australia. The blight injures plants by forming blockages in xylem and phloem, inhibiting resource distribution and resulting in plant die-back and smaller fruit yields. As of 2020 there is no cure for the blight, and neither the causal agent nor spreading mechanism is known. Description Citrus blight is a type of plant blight. The effects of citrus blight were first documented in the early 20th century. The disease afflicts plants in tropical and subtropical environments; regions impacted by the disease include North America and South America, the Caribbean, South Africa, and Australia. The important citrus-growing regions of California and the Mediterranean have not been effected. The blight spreads through an infected tree, invading and colonizing the plant's roots, le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symptom
Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showing on a medical scan. A symptom is something out of the ordinary that is experienced by an individual such as feeling feverish, a headache or other pain or pains in the body. Signs and symptoms Signs A medical sign is an objective observable indication of a disease, injury, or abnormal physiological state that may be detected during a physical examination, examining the patient history, or diagnostic procedure. These signs are visible or otherwise detectable such as a rash or bruise. Medical signs, along with symptoms, assist in formulating diagnostic hypothesis. Examples of signs include elevated blood pressure, nail clubbing of the fingernails or toenails, staggering gait, and arcus senilis and arcus juvenilis of the eyes. Indicati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacterium
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascomycota
Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The defining feature of this fungal group is the " ascus" (), a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of the Ascomycota are asexual, meaning that they do not have a sexual cycle and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens (loosely termed "ascolichens") such as ''Cladonia'' belong to the Ascomycota. Ascomycota is a monophyletic group (it contains all descendants of one common ancestor). Previously placed in the Deuteromycota along with asexual species from other fungal taxa, asexual (or anamorphic) ascomyce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bur Oak Blight
Bur oak blight (BOB) is a fungal disease that is relatively new to the plant pathogen field. BOB started to appear in Midwestern states in the 1990s. The first few diagnoses pointed to a common fungus, ''Tubakia dryina'', as the culprit. However upon further research BOB was said to be caused by a new unnamed species of '' Tubakia'', later named ''Tubakia iowensis''. BOB has severe symptoms and is a serious new problem. Hosts and symptoms The host for this disease is the bur oak ''Quercus macrocarpa'', the bur oak or burr oak, is a species of oak tree native to eastern North America. It is in the white oak section, ''Quercus'' sect. ''Quercus'', and is also called mossycup oak, mossycup white oak, blue oak, or scrub oa ..., ''Quercus macrocarpa''. Research shows that ''Q. macrocarpa var. olivaeformis'' tends to be the most susceptible to the pathogen, but the more common and widespread ''Q. macrocarpa var. macrocarpa'' has also been affected by BOB. ''Q. macrocarpa var. olivae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alternaria Triticina
''Alternaria triticina'' is a fungal plant pathogen that causes leaf blight on wheat. ''A. triticina'' is responsible for the largest leaf blight issue in wheat and also causes disease in other major cereal grain crops. It was first identified in India in 1962 and still causes significant yield loss to wheat crops on the Indian subcontinent. The disease is caused by a fungal pathogen and causes necrotic leaf lesions and in severe cases shriveling of the leaves. Hosts and symptoms Successful inoculation of ''A. triticina'' has been repeatedly confirmed in ''Triticum turgidum'' subsp. ''Durum'' (durum wheat) and ''Triticum aestivum'' (common wheat, bread wheat) with bread wheat varieties showing more severe infection.Systematic Mycology & Microbiology Laboratory “Alternaria Triticina (Leaf Blight of Wheat).” Invasive Species Compendium, CAB International, 2 Oct. 2019, www.cabi.org/isc/datasheet/4534. Barley, sorghum, triticale, oats, rye, and millet have all been experimentall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascochyta
''Ascochyta'' is a genus of ascomycete fungi, containing several species that are pathogenic to plants, particularly cereal crops. The taxonomy of this genus is still incomplete. The genus was first described in 1830 by Marie-Anne Libert, who regarded the spores as minute asci and the cell contents as spherical spores. Numerous revisions to the members of the genus and its description were made for the next several years. Species that are plant pathogenic on cereals include, '' A. hordei'', '' A. graminea'', '' A. sorghi'', '' A. tritici''. Symptoms are usually elliptical spots that are initially chlorotic and later become a necrotic brown. Management includes fungicide applications and sanitation of diseased plant tissue debris. Some of these pathogens in the genus ''Ascochyta'' affect grass species, including grains. Some species of ''Ascochyta'' *'' Ascochyta asparagina'', Ascochyta blight *'' Ascochyta bohemica'' *'' Ascochyta boltshauseri'' *'' Ascochyta caricae'', S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alternaria
''Alternaria'' is a genus of Deuteromycetes fungi. All species are known as major plant pathogens. They are also common allergens in humans, growing indoors and causing hay fever or hypersensitivity reactions that sometimes lead to asthma. They are present in the human mycobiome and readily cause opportunistic infections in immunocompromised people such as AIDS patients. There are 299 species in the genus; they are ubiquitous in the environment and are a natural part of fungal flora almost everywhere. They are normal agents of decay and decomposition. The spores are airborne and found in the soil and water, as well as indoors and on objects. The club-shaped spores are single or form long chains. They can grow thick colonies which are usually green, black, or gray. At least 20% of agricultural spoilage is caused by ''Alternaria'' species, with the most severe losses reaching 80% of yield. Many human health disorders can be caused by these fungi, which grow on skin and mucous me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burkholderia Plantarii
''Burkholderia plantarii'' is a Gram-negative soil bacterium. Its specific name comes from the Latin ''plantarium'' (seedbed).Garrity, George M.; Brenner, Don J.; Krieg, Noel R.; Staley, James T. (eds.) (2005). Bergey's Manual of Systematic Bacteriology, Volume Two: The Proteobacteria, Part C: The Alpha-, Beta-, Delta-, and Epsilonproteobacteria. New York, New York: Springer. . ''Burkholderia vandii'' is a synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ... of this species, which was named after the orchid '' Vanda'', where it was first found. References External linksType strain of ''Burkholderia plantarii'' at Bac''Dive'' - the Bacterial Diversity Metadatabase Burkholderiaceae Bacteria described in 1994 {{Betaproteobacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenazine
Phenazine is an organic compound with the formula (C6H4)2N2. It is a dibenzo annulation, annulated pyrazine, and the parent substance of many dyestuffs, such as the toluylene red, indulines, and safranines (and the closely related eurhodines). Phenazine crystallizes in yellow needles, which are only sparingly soluble in ethanol, alcohol. Sulfuric acid dissolves it, forming a deep-red solution. Synthesis Classically phenazine are prepared by the reaction of nitrobenzene and aniline in the Wohl-Aue reaction. Other methods include: * pyrolysis of the barium salt (chemistry), salt of azobenzoate * oxidation of aniline with lead oxide * oxidation of dihydrophenazine, which is prepared by heating pyrocatechin with o-phenylenediamine. * oxidation of ortho-aminodiphenylamine with lead peroxide. Derivatives * The more complex phenazines, such as the naphthophenazines, naphthazines, and naphthotolazines, may be prepared by condensing Toluidine, ortho-diamines with quinone, ortho-quinones or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthomonas Oryzae
''Xanthomonas oryzae'' is a species of bacteria. The major host of the bacterium is rice. The species contains two pathovars, neither of which is native to Europe: ''X. o.'' pv. ''oryzae'' and ''X. o.'' pv. ''oryzicola''. ''Xanthomonas oryzae'' epidemics can cause yield losses ranging from 2-74%, and the bacteria can be carried on rice seeds, causing further disease spread. The host resistance gene, ''Xa21'', from ''Oryza longistaminata'', is integrated into the genome of ''Oryza sativa ''Oryza sativa'', commonly known as Asian rice or indica rice, is the plant species most commonly referred to in English as ''rice''. It is the type of farmed rice whose cultivars are most common globally, and was first domesticated in the Yan ...'' for its broad-range resistance to rice leaf blight caused by ''X. o.'' pv. ''oryzae''. References External links Xanthomonas Genomics Resource web-based database and communication forum to facilitate genomic approaches to the study of xant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rice
Rice is the seed of the grass species ''Oryza sativa'' (Asian rice) or less commonly ''Oryza glaberrima ''Oryza glaberrima'', commonly known as African rice, is one of the two domesticated rice species. It was first domesticated and grown in West Africa around 3,000 years ago. In agriculture, it has largely been replaced by higher-yielding Asian r ...'' (African rice). The name wild rice is usually used for species of the genera ''Zizania (genus), Zizania'' and ''Porteresia'', both wild and domesticated, although the term may also be used for primitive or uncultivated varieties of ''Oryza''. As a cereal, cereal grain, domesticated rice is the most widely consumed staple food for over half of the world's World population, human population,Abstract, "Rice feeds more than half the world's population." especially in Asia and Africa. It is the agricultural commodity with the third-highest worldwide production, after sugarcane and maize. Since sizable portions of sugarcane and ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
