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Russian Wheat Aphid
The Russian wheat aphid (''Diuraphis noxia'') is an aphid that can cause significant losses in cereal crops. The species was introduced to the United States in 1986 and is considered an invasive species there. This aphid is pale green and up to 2 mm long. Cornicles are very short, rounded, and appear to be lacking. There is an appendage above the cauda giving the aphid the appearance of having two tails. The saliva of this aphid is toxic to the plant and causes whitish striping on cereal leaves. Feeding by this aphid will also cause the flag leaf to turn white and curl around the head causing incomplete head emergence. Its host plants are cereal grain crops including wheat and barley and to a lesser extent, wild grasses such as wheatgrasses, brome-grasses, ryegrasses and anything in the grass family. The Russian wheat aphid is native to southwestern parts of Asia. It was introduced to many countries in Europe and Africa. It was first found in the U.S. in 1986 in Texas. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aphid
Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A typical life cycle involves flightless females giving live birth to female nymphs—who may also be already pregnant, an adaptation scientists call telescoping generations—without the involvement of males. Maturing rapidly, females breed profusely so that the number of these insects multiplies quickly. Winged females may develop later in the season, allowing the insects to colonize new plants. In temperate regions, a phase of sexual reproduction occurs in the autumn, with the insects often overwintering as eggs. The life cycle of some species involves an alternation between two species of host plants, for example between an annual crop and a woody plant. Some species feed on only one type of plant, while others are generalists, coloni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugarcane Mosaic Virus
''Sugarcane mosaic virus'' (SCMV) is a plant pathogenic virus of the family ''Potyviridae''. The virus was first noticed in Puerto Rico in 1916 and spread rapidly throughout the southern United States in the early 1920s. SCMV is of great concern because of the high economic impact it has on sugarcane and maize. Hosts Sugarcane mosaic virus causes mosaic symptoms in sugarcane, maize, sorghum, and other poaceous plants. In sugarcane, this is the most widespread virus and 21 strains of it have been found in the United States. The SCMV complex has been shown to consist of four distinct potyviruses and includes strains of '' Johnsongrass mosaic virus'' (JGMV), ''maize dwarf mosaic virus'' (MDMV), '' sorghum mosaic virus'' (SrMV), and SCMV. CABI ISCbr>19952304874 Vectors The aphid ''Myzus persicae'' was first found to vector SCMV from sorghum to sorghum by Anzalone 1962. Symptoms Symptoms of sugarcane mosaic virus include intense mottling throughout the laminar region of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrosiphini
Macrosiphini is an aphid tribe in the subfamily Aphidinae. Genera The tribe includes the following genera, listed in alphabetical order: '' Abstrusomyzus'' - '' Acaudella'' - '' Acaudinum'' - '' Acuticauda'' - '' Acutosiphon'' - ''Acyrthosiphon'' - '' Akkaia'' - '' Allocotaphis'' - '' Alphitoaphis'' - '' Amegosiphon'' - '' Ammiaphis'' - '' Amphicercidus'' - '' Amphorophora'' - '' Amphorosiphon'' - '' Anaulacorthum'' - '' Anthracosiphon'' - '' Antimacrosiphon'' - '' Anuraphis'' - '' Anuromyzus'' - '' Aphidura'' - '' Aphiduromyzus'' - '' Aphthargelia'' - '' Artemisaphis'' - '' Aspidaphis'' - '' Aspidophorodon'' - '' Atarsos'' - '' Aulacophoroides'' - '' Aulacorthum'' - '' Avicennina'' - '' Berberidaphis'' - '' Bipersona'' - '' Blanchardaphis'' - '' Brachycaudus'' - '' Brachycolus'' - '' Brachycorynella'' - '' Brachymyzus'' - '' Brachysiphoniella'' - '' Brevicoryne'' - '' Brevicorynella'' - '' Brevisiphonaphis'' - '' Burundiaphis'' - '' Cac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kansas State University
Kansas State University (KSU, Kansas State, or K-State) is a public land-grant research university with its main campus in Manhattan, Kansas, United States. It was opened as the state's land-grant college in 1863 and was the first public institution of higher learning in the state of Kansas. It had a record high enrollment of 24,766 students for the Fall 2014 semester. The university is classified among "R1: Doctoral Universities – Very high research activity". Kansas State's academic offerings are administered through nine colleges, including the College of Veterinary Medicine and the College of Technology and Aviation in Salina. Graduate degrees offered include 65 master's degree programs and 45 doctoral degrees. Branch campuses are in Salina and Olathe. The Kansas State University Salina Aerospace and Technology Campus is home to the College of Technology and Aviation. The Olathe Innovation Campus has a focus on graduate work in research bioenergy, animal health, pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States National Agricultural Library
The United States National Agricultural Library (NAL) is one of the world's largest agricultural research libraries, and serves as a national library of the United States and as the library of the United States Department of Agriculture. Located in Beltsville, Maryland, it is one of five national libraries of the United States (along with the Library of Congress, the National Library of Medicine, the National Transportation Library, and the National Library of Education). It is also the coordinator for the Agriculture Network Information Center (AgNIC), a national network of state land-grant institutions and coordinator for the U.S. Department of Agriculture (USDA) field libraries. NAL was established on May 15, 1862, by the signing of the Organic Act by Abraham Lincoln. It served as a departmental library until 1962, when the Secretary of Agriculture officially designated it as the National Agricultural Library. The first librarian, appointed in 1867, was Aaron B. Grosh, one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardiness (plants)
Hardiness of plants describes their ability to survive adverse growing conditions. It is usually limited to discussions of climatic adversity. Thus a plant's ability to tolerate cold, heat, drought, flooding, or wind are typically considered measurements of hardiness. Hardiness of plants is defined by their native extent's geographic location: longitude, latitude and elevation. These attributes are often simplified to a hardiness zone. In temperate latitudes, the term most often describes resistance to cold, or "cold-hardiness", and is generally measured by the lowest temperature a plant can withstand. Hardiness of a plant is usually divided into two categories: tender, and hardy. (Some sources also use the erroneous terms "Half-hardy" or "Fully hardy".) Tender plants are those killed by freezing temperatures, while hardy plants survive freezing—at least down to certain temperatures, depending on the plant. "Half-hardy" is a term used sometimes in horticulture to describe bed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomass (ecology)
The biomass is the mass of living biological organisms in a given area or ecosystem at a given time. Biomass can refer to ''species biomass'', which is the mass of one or more species, or to ''community biomass'', which is the mass of all species in the community. It can include microorganisms, plants or animals. The mass can be expressed as the average mass per unit area, or as the total mass in the community. How biomass is measured depends on why it is being measured. Sometimes, the biomass is regarded as the natural mass of organisms ''in situ'', just as they are. For example, in a salmon fishery, the salmon biomass might be regarded as the total wet weight the salmon would have if they were taken out of the water. In other contexts, biomass can be measured in terms of the dried organic mass, so perhaps only 30% of the actual weight might count, the rest being water. For other purposes, only biological tissues count, and teeth, bones and shells are excluded. In some appl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turgor Pressure
Turgor pressure is the force within the cell that pushes the plasma membrane against the cell wall. It is also called ''hydrostatic pressure'', and is defined as the pressure in a fluid measured at a certain point within itself when at equilibrium. Generally, turgor pressure is caused by the osmotic flow of water and occurs in plants, fungi, and bacteria. The phenomenon is also observed in protists that have cell walls. This system is not seen in animal cells, as the absence of a cell wall would cause the cell to lyse when under too much pressure. The pressure exerted by the osmotic flow of water is called turgidity. It is caused by the osmotic flow of water through a selectively permeable membrane. Movement of water through a semipermeable membrane from a volume with a low solute concentration to one with a higher solute concentration is called osmotic flow. In plants, this entails the water moving from the low concentration solute outside the cell into the cell's vacuole. Mec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stunt (botany)
In botany and agriculture, stunting describes a plant disease that results in dwarfing and loss of vigor. It may be caused by infectious or noninfectious means. Infectious A stunt caused by infectious means usually is too late to cure. * Nematodes (eelworm) * Fungi * Bacteria * Viruses Noninfectious A stunt caused by noninfectious means could sometimes be remedied. * Physical environment ** Excess of water ** Lack of water ** Too-deep planting ** Excess light * Nutrition-related ** Soil nutrient imbalance * Injuries ** Chemical injury ** Physical injury ** Pest feeding See also * Soil retrogression and degradation * Soil pH * Soil types * Ramu stunt disease The Ramu stunt disease is a disease of the sugarcane widespread throughout Papua New Guinea, but not detected in Australia. ''Eumetopina flavipes'', the island sugarcane planthopper, is a species of planthopper present throughout South East Asia ..., a disease of the sugarcane widespread throughout Papua New Guine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilting
Wilting is the loss of rigidity of non-woody parts of plants. This occurs when the turgor pressure in non-lignified plant cells falls towards zero, as a result of diminished water in the cells. Wilting also serves to reduce water loss, as it makes the leaves expose less surface area. The rate of loss of water from the plant is greater than the absorption of water in the plant. The process of wilting modifies the leaf angle distribution of the plant (or canopy) towards more erectophile conditions. Lower water availability may result from: * drought conditions, where the soil moisture drops below conditions most favorable for plant functioning; * the temperature falls to the point where the plant's vascular system cannot function; * high salinity, which causes water to diffuse from the plant cells and induce shrinkage; * saturated soil conditions, where roots are unable to obtain sufficient oxygen for cellular respiration, and so are unable to transport water into the plant; or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Necrosis
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated digestion of cell components. In contrast, apoptosis is a naturally occurring programmed and targeted cause of cellular death. While apoptosis often provides beneficial effects to the organism, necrosis is almost always detrimental and can be fatal. Cellular death due to necrosis does not follow the apoptotic signal transduction pathway, but rather various receptors are activated and result in the loss of cell membrane integrity and an uncontrolled release of products of cell death into the extracellular space. This initiates in the surrounding tissue an inflammatory response, which attracts leukocytes and nearby phagocytes which eliminate the dead cells by phagocytosis. However, microbial damaging substances released by leukocytes would crea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
