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Pasteuria Penetrans
''Pasteuria'' is a genus of mycelial and endospore-forming, nonmotile gram-positive bacteria that are obligate parasites of some nematodes and crustaceans. The genus of ''Pasteuria'' was previously classified within the family Alicyclobacillaceae, but has since been moved to the family Pasteuriaceae. Steps of infection Animals that are susceptible to ''Pasteuria'' become infected when they are exposed to spores in soil or water. Therefore, ''Pasteuria'' are transmitted horizontally between hosts and when an infected host dies, it releases spores to the soil or sediment. The likelihood of infections is related to the spore density in the environment and can be affected by temperature. After contact with the host, ''Pasteuria'' spores are activated, attach to their host, penetrate the host's cuticle, proliferate within the host, and kill the host. In water fleas, the ability of the spore to successfully attach during the infection process is related to the genotype of the host a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
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 relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans (Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belonolaimus Longicaudatus
''Belonolaimus longicaudatus'' (Sting nematode) is a common parasite of grasses and other plant crops and products. It is the most destructive nematode pest of turf grass, and it also attacks a wide range of fruit, vegetable, and fiber crops such as citrus, cotton, ornamentals, and forage. The sting nematode is a migratory ectoparasite of roots. It is well established in many golf courses and presents a problem in turf management. The sting nematode is only present in very sandy soils. It cannot reproduce in heavier or clay soils. History The genus was originally described by Steiner in 1942 but because of WWII the work was not published until 1949 (''B. gracilis'', Steiner 1949). Rau (1958) further refined the anatomical description and clarified the genus to note that there were several species, most common of which is ''B. longicaudatus''. Description A long nematode compared to other plant parasitic nematodes at 2–3 mm for both the male and female. Description: The l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pratylenchus
''Pratylenchus'' is a genus of nematodes known commonly as lesion nematodes.Crow, W. TAmaryllis lesion nematode, ''Pratylenchus hippeastri''.EENY-546. University of Florida IFAS. 2012. They are parasitic on plants and are responsible for root lesion disease on many taxa of host plants in temperate regions around the world. Lesion nematodes are migratory endoparasites that feed and reproduce in the root and move around, unlike the cyst or root-knot nematodes, which may stay in one place. They usually only feed on the cortex of the root.Lesion nematodes. University of Illinois Extension. 1999. Species are distinguished primarily by the of the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladocera
The Diplostraca or Cladocera, commonly known as water fleas, are a superorder of small crustaceans that feed on microscopic chunks of organic matter (excluding some predatory forms). Over 1000 species have been recognised so far, with many more undescribed. The oldest fossils of diplostracans date to the Jurassic, though their modern morphology suggests that they originated substantially earlier, during the Paleozoic. Some have also adapted to a life in the ocean, the only members of Branchiopoda to do so, even if several anostracans live in hypersaline lakes. Most are long, with a down-turned head with a single median compound eye, and a carapace covering the apparently unsegmented thorax and abdomen. Most species show cyclical parthenogenesis, where asexual reproduction is occasionally supplemented by sexual reproduction, which produces resting eggs that allow the species to survive harsh conditions and disperse to distant habitats. Description They are mostly long, with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Root-knot Nematode
Root-knot nematodes are plant-parasitic nematodes from the genus ''Meloidogyne''. They exist in soil in areas with hot climates or short winters. About 2000 plants worldwide are susceptible to infection by root-knot nematodes and they cause approximately 5% of global crop loss. Root-knot nematode larvae infect plant roots, causing the development of root-knot galls that drain the plant's photosynthate and nutrients. Infection of young plants may be lethal, while infection of mature plants causes decreased yield. Economic impact Root-knot nematodes (''Meloidogyne'' spp.) are one of the three most economically damaging genera of plant-parasitic nematodes on horticultural and field crops. Root-knot nematodes are distributed worldwide, and are obligate parasites of the roots of thousands of plant species, including monocotyledonous and dicotyledonous, herbaceous and woody plants. The genus includes more than 90 species, with some species having several races. Four ''Meloidogyne'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potato Cyst Nematode
Potato root nematodes or potato cyst nematodes (PCN) are 1-mm long roundworms belonging to the genus ''Globodera'', which comprises around 12 species. They live on the roots of plants of the family Solanaceae, such as potatoes and tomatoes. PCN cause growth retardation and, at very high population densities, damage to the roots and early senescence of plants. The nematode is not indigenous to Europe but originates from the Andes. Fields are free from PCN until an introduction occurs, after which the typical patches, or hotspots, occur on the farmland. These patches can become full field infestations when unchecked. Yield reductions can average up to 60% at high population densities. Biology and life cycle The eggs hatch in the presence of Solanoeclepine A, a substance secreted by the roots of host plants otherwise known as root exudates. The nematodes hatch when they grow into a second-stage juvenile (J2). At this stage, the J2 nematodes find host cells to feed off of. The potat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera
''Heterodera'' is a genus of nematodes in the family Heteroderidae. Members of the genus are obligate parasites and different species attack different crops, often causing great economic damage. The genus is unique among nematode genera because of the ability of the female to transform into a tough, brown, cyst which protects the eggs which have been formed within her body. The name heterodera "refers to the different 'skins' of female and cyst."Tylenchida: Parasites of Plants and Insects, 2nd ed., by Mohammad Rafiq Siddiqi Diversity The following is a list of taxa in the genus ''Heterodera'': * ''Heterodera amygdali'' * '' Heterodera arenaria'' * '' Heterodera aucklandica'' * ''Heterodera avenae'' * '' Heterodera bergeniae'' * ''Heterodera bifenestra'' * '' Heterodera cacti'' * ''Heterodera cajani'' * '' Heterodera canadensis'' * '' Heterodera cardiolata'' * ''Heterodera carotae'' * '' Heterodera ciceri'' * ''Heterodera cruciferae'' * ''Heterodera delvii'' * '' Heterodera elachis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syngenta
Syngenta AG is a provider of agricultural science and technology, in particular seeds and pesticides with its management headquarters in Basel, Switzerland. It is owned by ChemChina, a Chinese state-owned enterprise. Syngenta was founded in 2000 by the merger of the agrichemical businesses of Novartis and AstraZeneca, and acquired by China National Chemical Corporation (ChemChina) in 2017. Its business units are Syngenta Crop Protection, Syngenta Seeds, Adama, and Syngenta Group China. In 2020, the Syngenta Group was formed, bringing together Syngenta, Adama, and the agricultural business of Sinochem under a single entity. Syngenta's primary products include pesticides, selective herbicides, non-selective herbicides, fungicides, insecticides, as well as corn, soya, and biofuel. Syngenta brands include Actara (Thiamethoxam), Agrisure (corn with Viptera trait), Alto (Cyproconazole), Amistar (azoxystrobin), Avicta, Axial, Bicep II, Bravo, Callisto, Celest, Cruiser (TMX, Thiamet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meloidogyne Javanica
''Meloidogyne javanica'' is a species of plant-pathogenic nematodes. It is one of the tropical root-knot nematodes and a major agricultural pest in many countries. It has many hosts. ''Meloidogyne javanica'' reproduces by obligatory mitotic parthenogenesis (apomixis). Hosts ''Meloidogyne javanica'' is a nematode pathogen that affects over 770 species of plants (Cabi 2018). The hosts of this pathogen include both weeds and crops of economic importance. Those of economic importance include tea, grapevine, vegetables, fruit trees, cereals, and ornamentals (Cabi 2018). ''Meloidogyne javanica'' is considered an agricultural pest, as it is extremely abundant and damaging (Alford 2012). Symptoms Because there are so many different hosts for this pathogen, the symptoms are very variable. Common symptoms include abnormal leaf color, abnormal leaf form, wilting leaves, galls, swollen roots, reduced root system, dwarfing and senescence (Cabi 2018). This pathogen does the most damage w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnia
''Daphnia'' is a genus of small planktonic crustaceans, in length. ''Daphnia'' are members of the order Anomopoda, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembles the movements of fleas. ''Daphnia'' spp. live in various aquatic environments ranging from acidic swamps to freshwater lakes and ponds. The two most commonly found species of ''Daphnia'' are '' D. pulex'' (small and most common) and '' D. magna'' (large). They are often associated with a related genus in the order Cladocera: ''Moina'', which is in the Moinidae family instead of the Daphniidae, and is much smaller than ''D. pulex'' (roughly half the maximum length). Appearance and characteristics The body of a ''Daphnia'' species is usually long, and is divided into segments, although this division is not visible. The head is fused, and is generally bent down towards the body with a visible notch separating the two. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alicyclobacillaceae
The Alicyclobacillaceae are a family of Gram-positive bacteria. All members of this family are aerobic and form endospores. The family contains four genera: ''Alicyclobacillus'', ''Effusibacillus'', '' Kyrpidia'', and '' Tumebacillus''. When originally created in 2009, Alicyclobacillaceae was a monophyletic family, only including genus ''Alicyclobacillus''. In 2011, the novel genus '' Kyrpidia'' was proposed and placed in family Alicyclobacillaceae, and '' Tumebacillus'' was placed into the family as well. In 2014, the novel genus ''Effusibacillus'' was proposed and added as the fourth member of Alicyclobacillaceae. ''Alicyclobacillus'' is the largest genus in Alicyclobacillaceae, with over 20 validly published species. The species are all acidophilic and have thermally resistant endospores. Many species are common soil organisms. Certain ''Alicyclobacillus'' species (especially '' A. acidoterrestris'') have been implicated in spoilage of pasteurized fruit juice. ''Effusibacill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
