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Sweet Potato Leaf Curl Virus
''Sweet potato leaf curl virus'' is commonly abbreviated SPLCV. Select isolates are referred to as SPLCV followed by an abbreviation of where they were isolated. For example, the Brazilian isolate is referred to as SPLCV-Br. The ''sweet potato leaf curl virus'' is one of more than 20 viruses known to infect the sweet potato. It is part of a group of sweet potato-infecting ''Begomoviruses'' generally known as "sweepoviruses". Viruses are common among sweet potatoes because their propagation is commonly dependent on stored roots or stems. Therefore, viruses can build up and have delayed emergence over the years. Viruses in sweet potatoes are problematic because they decrease crop yield and quality of storage roots. This is problematic as sweet potatoes are ranked seventh for global food crops. ''Sweet potato leaf curl virus'' is commonly transmitted from insect to plant by whiteflies (''Bemisia tabaci''). Additionally, it can be transmitted from plant to plant via vegetative propa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geminiviruses Drawing
''Geminiviridae'' is a family of plant viruses that encode their genetic information on a circular genome of single-stranded (ss) DNA. There are 520 species in this family, assigned to 14 genera. Diseases associated with this family include: bright yellow mosaic, yellow mosaic, yellow mottle, leaf curling, stunting, streaks, reduced yields. They have single-stranded circular DNA genomes encoding genes that diverge in both directions from a virion strand origin of replication (i.e. geminivirus genomes are ambisense). According to the Baltimore classification they are considered class II viruses. It is the largest known family of single stranded DNA viruses. Mastrevirus and curtovirus transmission is via various leafhopper species (e.g. maize streak virus and other African streak viruses are transmitted by ''Cicadulina mbila''), the only known topocuvirus species, ''Tomato pseudo-curly top virus'', is transmitted by the treehopper ''Micrutalis malleifera'', and begomoviruses are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buprofezin
Buprofezin is an insecticide used for control of insect pests such as mealybugs, leafhoppers and whitefly on vegetable crops. It is a growth regulator, acting as an inhibitor of chitin Chitin ( C8 H13 O5 N)n ( ) is a long-chain polymer of ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is probably the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chit ... synthesis. It is banned in some countries due to its negative environmental impacts, being especially toxic to aquatic organisms as well as non-target insects, though is of low toxicity to humans and other mammals.Qureshi IZ, Bibi A, Shahid S, Ghazanfar M. Exposure to sub-acute doses of fipronil and buprofezin in combination or alone induces biochemical, hematological, histopathological and genotoxic damage in common carp (Cyprinus carpio L.). ''Aquat Toxicol''. 2016 Oct;179:103-14. doi: 10.1016/j.aquatox.2016.08.012. References {{insecticides I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neonicotinoid
Neonicotinoids (sometimes shortened to neonics ) are a class of neuro-active insecticides chemically similar to nicotine, developed by scientists at Shell and Bayer in the 1980s. The neonicotinoid family includes acetamiprid, clothianidin, dinotefuran, imidacloprid, nitenpyram, nithiazine, thiacloprid and thiamethoxam. Imidacloprid has been the most widely used insecticide in the world from 1999 through . Compared to organophosphate and carbamate insecticides, neonicotinoids are less toxic to birds and mammals. Neonicotinoid use has been studied in relation to adverse ecological effects, including honey-bee colony collapse disorder (CCD), and declining populations of insect-eating birds. In 2013, the European Union and some neighbouring countries restricted the use of certain neonicotinoids. In 2018 the EU banned the three main neonicotinoids ( clothianidin, imidacloprid and thiamethoxam) for all outdoor uses, but in 2020, France re-allowed the use of neonicotinoids on sug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetamiprid
Acetamiprid is an organic compound with the chemical formula C10H11ClN4. It is an odorless neonicotinoid insecticide produced under the trade names Assail, and Chipco by Aventis CropSciences. It is systemic and intended to control sucking insects (Thysanoptera, Hemiptera, mainly aphids) on crops such as leafy vegetables, citrus fruits, pome fruits, grapes, cotton, cole crops, and ornamental plants. It is also a key pesticide in commercial cherry farming due to its effectiveness against the larvae of the cherry fruit fly. Acetamiprid is an insecticide belonging to the chloropyridinyl neonicotinoids, this family of insecticides was introduced in the early 1990s. This compound is an insecticide that is introduced for controlling pests, but also for domestic use to control fleas on cats and dogs. Structure and reactivity Acetamiprid is an α-chloro-N-heteroaromatic compound. It is a neonicotinoid with a chloropyridinyl group and it is comparable to other neonicotinoids such as imi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyriproxyfen
Pyriproxyfen is a pesticide which is found to be effective against a variety of insects. It was introduced to the US in 1996, to protect cotton crops against whitefly. It has also been found useful for protecting other crops. It is also used as a prevention for flea control on household pets, for killing indoor and outdoor ants and roaches. Methods of application include aerosols, bait, carpet powders, foggers, shampoos and pet collars. Pyriproxyfen is a juvenile hormone analog and an insect growth regulator. It prevents larvae from developing into adulthood and thus rendering them unable to reproduce. In the US, pyriproxyfen is often marketed under the trade name ''Nylar''. In Europe, pyriproxyfen is known under the brand names Cyclio ( Virbac) and Exil Flea Free TwinSpot (Emax). Toxicity in mammals Pyriproxyfen has low acute toxicity. According to WHO and FAO, at elevated doses exceeding 5000 mg/kg of body weight, pyriproxyfen affects the liver in mice, rats and dog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imidacloprid
Imidacloprid is a systemic insecticide belonging to a class of chemicals called the neonicotinoids which act on the central nervous system of insects. The chemical works by interfering with the transmission of stimuli in the insect nervous system. Specifically, it causes a blockage of the nicotinergic neuronal pathway. By blocking nicotinic acetylcholine receptors, imidacloprid prevents acetylcholine from transmitting impulses between nerves, resulting in the insect's paralysis and eventual death. It is effective on contact and via stomach action. Because imidacloprid binds much more strongly to insect neuron receptors than to mammal neuron receptors, this insecticide is more toxic to insects than to mammals. From 1999 through , imidacloprid was the most widely used insecticide in the world. Although it is now off patent, the primary manufacturer of this chemical is Bayer CropScience (part of Bayer AG). It is sold under many names for many uses; it can be applied by soil inj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymerase Chain Reaction
The polymerase chain reaction (PCR) is a method widely used to rapidly make millions to billions of copies (complete or partial) of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it (or a part of it) to a large enough amount to study in detail. PCR was invented in 1983 by the American biochemist Kary Mullis at Cetus Corporation; Mullis and biochemist Michael Smith, who had developed other essential ways of manipulating DNA, were jointly awarded the Nobel Prize in Chemistry in 1993. PCR is fundamental to many of the procedures used in genetic testing and research, including analysis of ancient samples of DNA and identification of infectious agents. Using PCR, copies of very small amounts of DNA sequences are exponentially amplified in a series of cycles of temperature changes. PCR is now a common and often indispensable technique used in medical laboratory research for a broad variety of applications including biomedical research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insecticide
Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a major factor behind the increase in the 20th-century's agricultural productivity. Nearly all insecticides have the potential to significantly alter ecosystems; many are toxic to humans and/or animals; some become concentrated as they spread along the food chain. Insecticides can be classified into two major groups: systemic insecticides, which have residual or long term activity; and contact insecticides, which have no residual activity. The mode of action describes how the pesticide kills or inactivates a pest. It provides another way of classifying insecticides. Mode of action can be important in understanding whether an insecticide will be toxic to unrelated species, such as fish, birds and mammals. Insecticides may be repe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemolymph
Hemolymph, or haemolymph, is a fluid, analogous to the blood in vertebrates, that circulates in the interior of the arthropod (invertebrate) body, remaining in direct contact with the animal's tissues. It is composed of a fluid plasma in which hemolymph cells called hemocytes are suspended. In addition to hemocytes, the plasma also contains many chemicals. It is the major tissue type of the open circulatory system characteristic of arthropods (e.g. arachnids, crustaceans and insects). In addition, some non-arthropods such as molluscs possess a hemolymphatic circulatory system. Oxygen-transport systems were long thought unnecessary in insects, but ancestral and functional hemocyanin has been found in the hemolymph. Insect "blood" generally does not carry hemoglobin, although hemoglobin may be present in the tracheal system instead and play some role in respiration. Method of transport In the grasshopper, the closed portion of the system consists of tubular hearts and an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Begomovirus
''Begomovirus'' is a genus of viruses, in the family ''Geminiviridae''. They are plant viruses that as a group have a very wide host range, infecting dicotyledonous plants. Worldwide they are responsible for a considerable amount of economic damage to many important crops such as tomatoes, beans, squash, cassava and cotton. There are 445 species in this genus. Morphology Virus particles are non-enveloped. The nucleocapsid is 38 nanometers (nm) long and 15–22 nm in diameter. While particles have basic icosahedral symmetry, they consist of two incomplete icosahedra—missing one vertex—joined together. There are 22 capsomeres per nucleocapsid. Genome Single stranded closed circular DNA. Many begomoviruses have a bipartite genome: this means that the genome is segmented into two segments (referred to as DNA A and DNA B) that are packaged into separate particles. Both segments are generally required for successful symptomatic infection in a host cell but DNA B is depe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweet Potato
The sweet potato or sweetpotato ('' Ipomoea batatas'') is a dicotyledonous plant that belongs to the bindweed or morning glory family, Convolvulaceae. Its large, starchy, sweet-tasting tuberous roots are used as a root vegetable. The young shoots and leaves are sometimes eaten as greens. Cultivars of the sweet potato have been bred to bear tubers with flesh and skin of various colors. Sweet potato is only distantly related to the common potato (''Solanum tuberosum''), both being in the order Solanales. Although darker sweet potatoes are often referred to as "yams" in parts of North America, the species is not a true yam, which are monocots in the order Dioscoreales. Sweet potato is native to the tropical regions of the Americas. Of the approximately 50 genera and more than 1,000 species of Convolvulaceae, ''I. batatas'' is the only crop plant of major importance—some others are used locally (e.g., ''I. aquatica'' "kangkong"), but many are poisonous. The genus ''Ipomo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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