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Gibberellin
Gibberellins (GAs) are plant hormones that regulate various developmental processes, including stem elongation, germination, dormancy, flowering, flower development, and leaf and fruit senescence. GAs are one of the longest-known classes of plant hormone. It is thought that the selective breeding (albeit unconscious) of crop strains that were deficient in GA synthesis was one of the key drivers of the "green revolution" in the 1960s, a revolution that is credited to have saved over a billion lives worldwide. History The first inroads into the understanding of GAs were developments from the plant pathology field, with studies on the ''bakanae'', or "foolish seedling" disease in rice. Foolish seedling disease causes a strong elongation of rice stems and leaves and eventually causes them to topple over. In 1926, Japanese scientist Eiichi Kurosawa identified that foolish seedling disease was caused by the fungus ''Gibberella fujikuroi.'' Later work at the University of Tokyo showed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paclobutrazol
Paclobutrazol (PBZ) is the ISO common name for an organic compound that is used as a plant growth retardant and triazole fungicide. It is a known antagonist of the plant hormone gibberellin, acting by inhibiting gibberellin biosynthesis, reducing internodal growth to give stouter stems, increasing root growth, causing early fruitset and increasing seedset in plants such as tomato and pepper. PBZ has also been shown to reduce frost sensitivity in plants. Moreover, paclobutrazol can be used as a chemical approach for reducing the risk of lodging in cereal crops. PBZ has been used by arborists to reduce shoot growth and shown to have additional positive effects on trees and shrubs. Among those are improved resistance to drought stress, darker green leaves, higher resistance against fungi and bacteria, and enhanced development of roots. Cambial growth, as well as shoot growth, has been shown to be reduced in some tree species. Structure and synthesis The first synthesis of pacl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Revolution
The Green Revolution, also known as the Third Agricultural Revolution, was a period of technology transfer initiatives that saw greatly increased crop yields and agricultural production. These changes in agriculture began in developed countries after World War II and spread globally till the late 1980s. In the late 1960s, farmers began incorporating new technologies such as high-yielding varieties of cereals, particularly dwarf wheat and rice, and the widespread use of chemical fertilizers, pesticides, and controlled irrigation. Agriculture also saw the adoption of newer methods of cultivation, including mechanization. These changes were often implemented as a package of practices meant to replace traditional agricultural technology. Both the Ford Foundation and the Rockefeller Foundation were heavily involved in its initial development in Mexico. One key leader was agricultural scientist Norman Borlaug, the "Father of the Green Revolution", who received the Nobel Peace P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germination
Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ferns, bacteria, and the growth of the pollen tube from the pollen grain of a seed plant. Seed plants Germination is usually the growth of a plant contained within a seed; it results in the formation of the seedling. It is also the process of reactivation of metabolic machinery of the seed resulting in the emergence of radicle and plumule. The seed of a vascular plant is a small package produced in a fruit or cone after the union of male and female reproductive cells. All fully developed seeds contain an embryo and, in most plant species some store of food reserves, wrapped in a seed coat. Some plants produce varying numbers of seeds that lack embryos; these are empty seeds which never germinate. Dormant seeds are viable seeds th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sultana (grape)
The sultana is a "white" (pale green), oval seedless grape variety also called the sultanina, Thompson Seedless (United States), Lady de Coverly (England), and oval-fruited Kishmish ( Iraq, Iran, Israel, Palestine, Pakistan, Afghanistan, India). It is also known as İzmir üzümü (grape of İzmir) in Turkey since this variety has been extensively grown in the region around İzmir. It is assumed to originate from Asia Minor, which later became part of the Ottoman Empire. In some countries, especially Commonwealth countries, the name ''sultana'' is used for the raisin made from it or larger seedless grapes; such ''sultana raisins'' are often called sultanas or sultanis. History American sultana grapes are almost invariably Thompson Seedless, a name that refers to William Thompson, a viticulturist who was an early grower in California and is sometimes credited with introducing the variety. According to the US Code of Federal Regulations, the two names are synonymous. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gibberellic Acid
Gibberellic acid (also called gibberellin A3, GA, and GA3) is a hormone found in plants and fungi. Its chemical formula is C19H22O6. When purified, it is a white to pale-yellow solid. Plants in their normal state produce large amounts of GA3. It is possible to produce the hormone industrially using microorganisms.Camara, M. C. et al (2015) General Aspects and Applications of Gibberelins and Gibberellic Acid in Plants. In: Hardy, J.. (Org.). Gibberellins and Gibberellic Acid: Biosynthesis, Regulation and Physiological Effects. 1ed.Hauppauge: Nova Science Publishers, 2015, v., p. 1-21. Gibberellic acid is a simple gibberellin, a pentacyclic diterpene acid promoting growth and elongation of cells. It affects decomposition of plants and helps plants grow if used in small amounts, but eventually plants develop tolerance to it. GA stimulates the cells of germinating seeds to produce mRNA molecules that code for hydrolytic enzymes. Gibberellic acid is a very potent hormone whose natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gibberella Fujikuroi
''Gibberella fujikuroi'' is a fungal plant pathogen. It causes ''bakanae'' disease in rice seedlings. Another name is foolish seedling disease. It gets that name because the seeds can be infected, leading to disparate outcomes for the plant. There are not many diseases that initiate similar symptoms as bakanae. Hosts and symptoms ''Gibberella fujikuroi'' is most widely known for its disease producing capabilities in rice, but barley, millet, sugarcane and maize are also susceptible. In all infected plants, similar symptoms have been found, though rice has been most predominantly studied. The most telltale symptom of Bakanae is the tall, spindly look of the plant. This is a result of the gibberellins, or growth hormones, the fungus secretes. Infected plants are easy to pick out, then, as they often rise above the rest of the healthy plants with regularly secreted growth hormones. However, it is also possible that stunting may occur, along with Chlorosis of the leaves of the pl ... [...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'' (African rice). The name wild rice is usually used for species of the genera '' Zizania'' and '' Porteresia'', both wild and domesticated, although the term may also be used for primitive or uncultivated varieties of '' Oryza''. As a cereal grain, domesticated rice is the most widely consumed staple food for over half of the world's 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 maize crops are used for purposes other than human consumption, rice is the most important food crop with regard to human nutrition and caloric intake, providing more than one-fifth of the calories consumed worldwide by humans. There are many varieties of rice and culinary preferences tend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gibberellic Acid
Gibberellic acid (also called gibberellin A3, GA, and GA3) is a hormone found in plants and fungi. Its chemical formula is C19H22O6. When purified, it is a white to pale-yellow solid. Plants in their normal state produce large amounts of GA3. It is possible to produce the hormone industrially using microorganisms.Camara, M. C. et al (2015) General Aspects and Applications of Gibberelins and Gibberellic Acid in Plants. In: Hardy, J.. (Org.). Gibberellins and Gibberellic Acid: Biosynthesis, Regulation and Physiological Effects. 1ed.Hauppauge: Nova Science Publishers, 2015, v., p. 1-21. Gibberellic acid is a simple gibberellin, a pentacyclic diterpene acid promoting growth and elongation of cells. It affects decomposition of plants and helps plants grow if used in small amounts, but eventually plants develop tolerance to it. GA stimulates the cells of germinating seeds to produce mRNA molecules that code for hydrolytic enzymes. Gibberellic acid is a very potent hormone whose natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dormancy
Dormancy is a period in an organism's life cycle when growth, development, and (in animals) physical activity are temporarily stopped. This minimizes metabolic activity and therefore helps an organism to conserve energy. Dormancy tends to be closely associated with environmental conditions. Organisms can synchronize entry to a dormant phase with their environment through predictive or consequential means. Predictive dormancy occurs when an organism enters a dormant phase ''before'' the onset of adverse conditions. For example, photoperiod and decreasing temperature are used by many plants to predict the onset of winter. Consequential dormancy occurs when organisms enter a dormant phase ''after'' adverse conditions have arisen. This is commonly found in areas with an unpredictable climate. While very sudden changes in conditions may lead to a high mortality rate among animals relying on consequential dormancy, its use can be advantageous, as organisms remain active longer an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bakanae
or bakanae disease (, , ), from the Japanese for "foolish seedling", is a disease that infects the rice plant. It is caused by the fungus ''Gibberella fujikuroi'', the metabolism of which produces a surplus of gibberellic acid. In the plant, this acts as a growth hormone, causing hypertrophy. The affected plants, which are visibly etiolated and chlorotic, are at best infertile with empty panicles, producing no edible grains; at worst, they are incapable of supporting their own weight, topple over, and die (hence "foolish seedling disease"). The earliest known report of ''bakanae'' is from 1828; it was first described scientifically in 1898 by Japanese researcher Shotaro Hori, who showed that the causative agent was fungal. at Plant-Hormones.info The fungus affects rice crops in Asia, Africa, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Hormone
Plant hormone (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, from embryogenesis, the regulation of organ size, pathogen defense, stress tolerance and through to reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book. Phytohormones occur across the plant kingdom, and even in algae, where they have similar functions to those seen in higher plants. Some phytohormones also occur in microorganisms, such as unicellular fungi and bacteria, however in these cases they do not play a hormonal role and can better be regarded as secondary metabolites. Characteristics The word hormone is derived from Greek, meaning ''set in motion''. Plant hormones affect gene expre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactone
Lactones are cyclic carboxylic esters, containing a 1-oxacycloalkan-2-one structure (), or analogues having unsaturation or heteroatoms replacing one or more carbon atoms of the ring. Lactones are formed by intramolecular esterification of the corresponding hydroxycarboxylic acids, which takes place spontaneously when the ring that is formed is five- or six-membered. Lactones with three- or four-membered rings (α-lactones and β-lactones) are very reactive, making their isolation difficult. Special methods are normally required for the laboratory synthesis of small-ring lactones as well as those that contain rings larger than six-membered. Nomenclature Lactones are usually named according to the precursor acid molecule (''aceto'' = 2 carbon atoms, ''propio'' = 3, ''butyro'' = 4, ''valero'' = 5, ''capro'' = 6, etc.), with a ''-lactone'' suffix and a Greek letter prefix that specifies the number of carbon atoms in the heterocycle — that is, the distance between the relevant -OH ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
