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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] |
Heterodera Avenae
''Heterodera avenae'', the cereal cyst nematode or European cyst nematode, is a plant pathogen and an obligate parasite of cereal crops including barley, oats, wheat and rye. Cereal crops infected with this nematode are more susceptible to infection by fungal diseases such as rhizoctonia root rot. Life cycle This microscopic nematode exhibits sexual dimorphism. The female is rounded and white and measures 680 by 930 micrometres. The male is vermiform and transparent and measures 40 by 1300 micrometres. The Egg (biology), eggs are oval and the vermiform larvae moult four times. The second instar larvae are mobile and can travel distances of up to thirty centimetres, looking for and invading roots of suitable host species. Here they develop, growing into sedentary bottle-shaped third instar larvae and rounded fourth instar ones. These then develop into either females or males and mating takes place. The female retains the majority of the several hundred eggs she produces inside her ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Medicaginis
''Heterodera medicaginis'', the alfalfa cyst nematode, is a plant pathogenic nematode which is cited as an invasive species. It is closely allied to '' Heterodera daverti'', '' H. glycines'' and '' H. sonchophila'' in the H. schachtii-group. The only known host plant of this obligate parasite is the important crop alfalfa or lucerne, ''Medicago sativa''. __TOC__ Description The female alfalfa cyst nematode is white and shaped like a lemon with a body length of 0.4 to 1.2 mm and a width of 0.2 to 0.9 mm. The male is vermiform with a body length of 1.2 to 1.4 mm and a width of about 0.028 mm. The eggs are reniform, measuring 0.12 by 0.05 mm and the first two instar larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...e are vermiform. The second instar larva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Carotae
''Heterodera carotae'' is a plant pathogenic nematode commonly known as the carrot root nematode or carrot cyst nematode. It is found in Europe, Cyprus and India and is considered an invasive species in the United States. It causes damage to carrot crops and is very specific in its choice of hosts, only infecting ''Daucus carota'' and '' Daucus pulcherrima''. Distribution In Europe this nematode has been recorded in Germany, France, Portugal, Italy, Hungary, Poland, Sweden, Russia, the Czech Republic, the Netherlands, the United Kingdom and Ireland. It has also been found in India and Cyprus and at several locations in the state of Michigan in the United States of America. Morphology The female carrot cyst nematode is white and lemon-shaped, averaging 400 μm by 300 μm, with a pair of ovaries occupying most of the body cavity. The male is threadlike, short with a rounded tail and a single testis averaging 60% of the body length. The mature cyst is lemon-shaped, white a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Cajani
''Heterodera cajani'' (Pigeonpea cyst nematode, Cowpea cyst nematode) is a plant pathogenic nematode affecting pigeonpeas, which is cited as an invasive species. See also * List of pigeonpea diseases References Heterodera, cajani Vegetable diseases Agricultural pest nematodes Nematodes described in 1967 {{agri-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Goettingiana
''Heterodera goettingiana'', the pea cyst nematode, is a plant pathogenic nematode affecting pea found in the United kingdom. See also * List of pea diseases This article is a list of diseases of peas (''Pisum sativum''). Bacterial diseases Fungal diseases Nematodes, parasitic Viral diseases {, class="wikitable" style="clear" ! colspan=2, Viral diseases , - , Cucumber mosaic virus , , gen ... * Agriculture of the United Kingdom References External links Nemaplex, University of California - Heterodera goettingiana goettingiana Plant pathogenic nematodes Pulse crop diseases Nematodes described in 1892 {{plant-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Glycines
The soybean cyst nematode (SCN), ''Heterodera glycines'', is the most devastating pest to soybean crop yields in the U.S., targeting the roots of soybean and other legume plants. When infection is severe SCNs cause stunting, yellowing, impaired canopy development, and yield loss. The symptoms caused by SCNs can go easily unrecognized by farmers—in some cases there are no warning symptoms before a loss of 30% of the yield.“You can literally have 40% yield loss with no symptoms,” says Greg Tylka, Iowa State University (ISU) Extension nematologist. Due to the slight stunting and yellowing, many farmers may mistake these symptoms as environmental problems when in fact they are SCNs. Another symptom of SCNs that may affect farmers' yields is stunted roots with fewer nitrogen-fixing nodules. Due to the fact that soybean cyst nematodes can only move a few centimeters in the soil by themselves, they mostly are spread via tillage or plant transplants. This area of infection will look ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Longicaudata
''Heterodera bifenestra'' (cereal cyst nematode) a Grain Genes is a plant pathogenic nematode, that is a causal agent of the cereal cyst nematode. References bifenestra Plant pathogenic nematodes[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Humuli
''Heterodera humuli'' is a plant pathogenic nematode, the hop cyst nematode. It is an obligate parasite and infests hop plants, ''Humulus lupulus''. Description The female hop cyst nematode is white and lemon-shaped with a body length of and a width of . The male is transparent and vermiform with a body length . The eggs are oval, and the first two instar larvae are vermiform. The second instar larvae are mobile in damp soil and invade suitable roots. Here they develop further and become sedentary, burying their heads in cells and feeding on the cell sap. The central part of their bodies swells, and after moulting again they develop into bottle-shaped third instar larvae and then thicker lemon-shaped fourth instar larvae. At this stage they either become male or female depending on the food supply. The swollen larval bodies break out of the root and the mobile males travel through the soil while the females remain attached to the root tissues by their heads. After inseminatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Cruciferae
''Heterodera cruciferae'' is a plant pathogenic nematode. External links cruciferae Brassicaceae () or (the older) Cruciferae () is a medium-sized and economically important family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous plants, while some are shrubs. The leav ... Plant pathogenic nematodes Nematodes described in 1945 {{plant-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Bifenestra
''Heterodera bifenestra'' (cereal cyst nematode) a Grain Genes is a plant pathogenic nematode, that is a causal agent of the cereal cyst nematode. References bifenestra Plant pathogenic nematodes[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Amygdali
''Heterodera amygdali'' is a plant pathogenic nematode native to Tajikistan Tajikistan (, ; tg, Тоҷикистон, Tojikiston; russian: Таджикистан, Tadzhikistan), officially the Republic of Tajikistan ( tg, Ҷумҳурии Тоҷикистон, Jumhurii Tojikiston), is a landlocked country in Centr .... Notes References *Kir'yanova, E. S.; Ivanova, T. S. 1975 Izvestiya Akademii Nauk Tadzhikskoi deg SSR Ahboroti Akademijai Fanhoi RSS Rocikiston, Otdelenie Biologicheskikh Nauk (3(60)): 52-56 amygdali Plant pathogenic nematodes Fauna of Tajikistan Nematodes described in 1975 {{plant-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterodera Delvii
''Heterodera delvii'' (cereal cyst nematode) is a plant pathogenic nematode, who is cited as an invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad .... Notes References * Jairajpur, M. Shamim; Khan, VC'ajih U.; Setty, K. G. H.; Govindu, H. C.''Heterodera delvii'' n. sp. (Nematoda: Heteroderidae), a parasite of ragi (''Eleusine coracana'') in Bangalore, India.''Revue de Nématologie 2(1) 1979:3-9.'' delvii Plant pathogenic nematodes Nematodes described in 1979 {{agri-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |