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Elm Yellows
Elm yellows is a plant disease of elm trees that is spread by leafhoppers or by root grafts."Elm Yellows." Elmcare.Com. 19 Mar. 2008 . Elm yellows, also known as elm phloem necrosis, is very aggressive, with no known cure. Elm yellows occurs in the eastern United States, and southern Ontario in Canada. It is caused by phytoplasmas which infect the phloem (inner bark) of the tree.Price, Terry. "Wilt Diseases." Forestpests.Org. 23 Mar. 2005. 19 Mar. 2008 . Similar phytoplasmas, also known confusingly as 'Elm yellows', also occur in Europe.Conti, M., D'Agostino, G., Mittembergher, L. (1987) A recent epiphytotic of elm yellows in Italy. ''Proceedings of the 7th Congress of the Mediterranean Phytopathological Union'', 208–209. Consejeria de Agricultura y Pesca de la Junta de Andalucia, Granada, Spain Infection and death of the phloem effectively girdles the tree and stops the flow of water and nutrients. The disease affects both wild-growing and cultivated trees. Importance Elms are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoplasma
Phytoplasmas are obligate intracellular parasites of plant phloem tissue and of the insect vectors that are involved in their plant-to-plant transmission. Phytoplasmas were discovered in 1967 by Japanese scientists who termed them mycoplasma-like organisms. Since their discovery, phytoplasmas have resisted all attempts at ''in vitro'' culture in any cell-free medium; routine cultivation in an artificial medium thus remains a major challenge. Phytoplasmas are characterized by the lack of a cell wall, a pleiomorphic or filamentous shape, a diameter normally less than 1 μm, and a very small genome. Phytoplasmas are pathogens of agriculturally important plants, including coconut, sugarcane, and sandalwood, in which they cause a wide variety of symptoms ranging from mild yellowing to death. Phytoplasmas are most prevalent in tropical and subtropical regions. They are transmitted from plant to plant by vectors (normally sap-sucking insects such as leafhoppers) in which they both sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
State College, Pennsylvania
State College is a home rule municipality in Centre County in the Commonwealth of Pennsylvania. It is a college town, dominated economically, culturally and demographically by the presence of the University Park campus of the Pennsylvania State University (Penn State). State College is the largest designated borough in Pennsylvania. It is the principal borough of the six municipalities that make up the State College area, the largest settlement in Centre County and one of the principal cities of the greater State College-DuBois Combined Statistical Area with a combined population of 236,577 as of the 2010 U.S. census. In the 2010 census, the borough population was 42,034 with approximately 105,000 living in the borough plus the surrounding townships often referred to locally as the "Centre Region". Many of these Centre Region communities also carry a "State College, PA" address although they are not part of the borough of State College. "Happy Valley" and "Lion Country" are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Wall
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mechanism. Cell walls are absent in many eukaryotes, including animals, but are present in some other ones like fungi, algae and plants, and in most prokaryotes (except mollicute bacteria). A major function is to act as pressure vessels, preventing over-expansion of the cell when water enters. The composition of cell walls varies between taxonomic group and species and may depend on cell type and developmental stage. The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicelluloses and pectin. Often, other polymers such as lignin, suberin or cutin are anchored to or embedded in plant cell walls. Algae possess cell walls made of glycoproteins and polysaccharides such as carrageenan and agar that are absent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosome
Ribosomes ( ) are macromolecular machines, found within all cells, that perform biological protein synthesis (mRNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA (mRNA) molecules to form polypeptide chains. Ribosomes consist of two major components: the small and large ribosomal subunits. Each subunit consists of one or more ribosomal RNA (rRNA) molecules and many ribosomal proteins (RPs or r-proteins). The ribosomes and associated molecules are also known as the ''translational apparatus''. Overview The sequence of DNA that encodes the sequence of the amino acids in a protein is transcribed into a messenger RNA chain. Ribosomes bind to messenger RNAs and use their sequences for determining the correct sequence of amino acids to generate a given protein. Amino acids are selected and carried to the ribosome by transfer RNA (tRNA) molecules, which enter the ribosome and bind to the messenger RNA chain via an anti-c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transfer RNA
Transfer RNA (abbreviated tRNA and formerly referred to as sRNA, for soluble RNA) is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length (in eukaryotes), that serves as the physical link between the mRNA and the amino acid sequence of proteins. tRNAs genes from Bacteria are typically shorter (mean = 77.6 bp) than tRNAs from Archaea (mean = 83.1 bp) and eukaryotes (mean = 84.7 bp). The mature tRNA follows an opposite pattern with tRNAs from Bacteria being usually longer (median = 77.6 nt) than tRNAs from Archaea (median = 76.8 nt), with eukaryotes exhibiting the shortest mature tRNAs (median = 74.5 nt). Transfer RNA (tRNA) does this by carrying an amino acid to the protein synthesizing machinery of a cell called the ribosome. Complementation of a 3-nucleotide codon in a messenger RNA (mRNA) by a 3-nucleotide anticodon of the tRNA results in protein synthesis based on the mRNA code. As such, tRNAs are a necessary component of translation, the biological sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetracycline
Tetracycline, sold under various brand names, is an oral antibiotic in the tetracyclines family of medications, used to treat a number of infections, including Acne vulgaris, acne, cholera, brucellosis, plague (disease), plague, malaria, and syphilis. Common side effects include vomiting, diarrhea, rash, and loss of appetite. Other side effects include poor tooth development if used by children less than eight years of age, kidney problems, and sunburning easily. Use during pregnancy may harm the baby. It works by inhibiting protein synthesis in bacteria. Tetracycline was patented in 1953 and came into commercial use in 1978. It is on the World Health Organization's List of Essential Medicines. Tetracycline is available as a generic medication. Tetracycline was originally made from bacteria of the genus ''Streptomyces''. Medical uses Spectrum of activity Tetracyclines have a broad spectrum of antibiotic action. Originally, they possessed some level of bacteriostatic acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trench Digger Lge
A trench is a type of excavation or in the ground that is generally deeper than it is wide (as opposed to a wider gully, or ditch), and narrow compared with its length (as opposed to a simple hole or pit). In geology, trenches result from erosion by rivers or by geological movement of tectonic plates. In civil engineering, trenches are often created to install underground utilities such as gas, water, power and communication lines. In construction, trenches are dug for foundations of buildings, retaining walls and dams, and for cut-and-cover construction of tunnels. In archaeology, the "trench method" is used for searching and excavating ancient ruins or to dig into strata of sedimented material. In geotechnical engineering, trenches serve for locating faults and investigating deep soil properties. In trench warfare, soldiers occupy trenches to protect them against weapons fire. Trenches are dug by use of manual tools such as shovels and pickaxes, or by heavy equipment such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birch Beer
Birch beer is a beverage, commonly found as a carbonated soft drink made from herbal extracts and birch bark. It was originally made from the extracts of both oak and pine barks (which are sometimes combined). There are dozens of brands of birch beer available. Ingredients The one ingredient used in all recipes of Birch beer is birch sap. Most recipes use some fermentation, but the amount of alcohol in the beverage depends on the brand. The process of fermenting birch syrup is done using baker's yeast. The process of fermentation is done to decompose sugar to alcohol. Other common ingredients include sugar, cinnamon, vanilla beans, and water. Homemade recipes of Birch beer also include honey and malt. Birch extract preparation Various types of birch beer made from birch bark are available as well, distinguished by color. The color depends on the species of birch tree from which the birch oil is extracted (though enhancements by artificial coloring are commonly present). Pop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Betula Lenta
''Betula lenta'' (sweet birch, also known as black birch, cherry birch, mahogany birch, or spice birch) is a species of birch native to eastern North America, from southern Maine west to southernmost Ontario, and south in the Appalachian Mountains to northern Georgia. Characteristics and habitat ''Betula lenta'' is a medium-sized deciduous tree reaching tall, exceptionally to with a trunk up to diameter. Heights of to are more typical. In younger trees the bark is characteristic of most birches, with smooth bark and distinct horizontal lenticels. It is sometimes mistakenly identified as a cherry tree. In older tree specimens the bark (unlike the more commonly known birches) develops vertical cracks into irregular scaly plates revealing rough dark brown bark patterns. This, however, only occurs in mature, or ancient, trees and these specimens are not often identified by the public as ''B. lenta'' due to the difference between the tree's smooth young bark (which the public ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allygus
''Allygus'' is a genus of true bugs belonging to the family Cicadellidae. The genus was first described by Fieber in 1875. The species of this genus are found in Europe and Northern America. Species: * ''Allygus mixtus'' References {{Taxonbar, from=Q10406490 Cicadellidae Hemiptera genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philaenus
''Philaenus'' is a genus of insects belonging to the family Aphrophoridae, the spittlebugs. The meadow spittlebug '' Philaenus spumarius'' is a common insect in much of the Northern Hemisphere, and it is sometimes a pest on crops such as alfalfa. It is important to science because its entire genome has been sequenced. It has also been the subject of many studies of genetic diversity because it displays marked color polymorphism. There are sixteen color phenotype In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...s, with individuals taking various dark, pale, mottled, and striped patterns. Most other ''Philaenus'' species are also color polymorphic. Many species are polyphagous, feeding on a number of plants. Some species specialize on one host plant, the common asphodel (''Asphod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
