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Rhopalosiphum Maidis
''Rhopalosiphum maidis'', common names corn leaf aphid and corn aphid, is an insect, and a pest of maize and other crops. It has a nearly worldwide distribution and is typically found in agricultural fields, grasslands, and forest-grassland zones. Among aphids that feed on maize, it is the most commonly encountered and most economically damaging, particularly in tropical and warmer temperate areas. In addition to maize, ''R. maidis'' damages rice, sorghum, and other cultivated and wild monocots. Description The bodies of wingless parthenogenetic females are green or whitish-green. The head, antennae, legs, cornicles, tail, and transverse bands on the abdomen are black-brown. The body has sparse short hairs. The length of the antennae is less than half the length of the body. Cornicles are not longer than the finger-like tail. In winged females, the head and thoracic section are black-brown and the cornicles are shorter than in the wingless females. Most ''R. maidis'' populat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asa Fitch
Asa Fitch (February 24, 1809 – April 8, 1879) was a natural historian and entomologist from Salem, New York. His early studies were of both natural history and medicine, which he studied at the newly formed Rensselaer Polytechnic Institute, graduating in 1827. However, in 1838 he decided to start studying agriculture and entomology. In 1838 he began to collect and study insects for New York state. In 1854 he became the first professional entomologist of New York State Agricultural Society (commissioned by the State of New York). This made him the first occupational entomologist in the United States. His vast studies of many insects helped scientists to solve some of the problems of crop damage caused by insects. Many of his notebooks are now the property of the Smithsonian Institution. Fitch also discovered the rodent botfly ''Cuterebra emasculator'' in 1856. He died April 8, 1879, in Salem, New York. The Martin–Fitch House and Asa Fitch Jr. Laboratory was added to the Nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parthenogenesis
Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development of embryos occur in a gamete (egg or sperm) without combining with another gamete (e.g., egg and sperm fusing). In animals, parthenogenesis means development of an embryo from an unfertilized Gametophyte, egg cell. In plants, parthenogenesis is a component process of apomixis. In algae, parthenogenesis can mean the development of an embryo from either an individual sperm or an individual egg. Parthenogenesis occurs naturally in some plants, algae, invertebrate animal species (including nematodes, some tardigrades, water fleas, some scorpions, aphids, some mites, some bees, some Phasmatodea and parasitic wasps) and a few vertebrates (such as some fish, amphibians, reptiles and birds). This type of reproduction has been induced artificially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metopolophium Dirhodum
''Metopolophium dirhodum'', the rose-grain aphid or rose-grass aphid, is a species of sap-sucking insect in the family Aphididae found worldwide. Its primary host is rose, and its secondary host is a grass, including cereals such as wheat, barley, oats and rye. It is an important vector of the barley yellow dwarf virus (BYDV) which causes serious reductions in yields of affected crops. Distribution The rose-grass aphid has an almost cosmopolitan distribution, being found in most parts of the world where its secondary hosts are grown. It was first detected in New Zealand in 1982. Description Wingless adults are between long, slender, glossy yellowish-green with a darker dorsal stripe. The antennae, legs and siphunculi (erect, backward-pointing tubes on the abdomen) are relatively long and pale in colour. Winged individuals are between long and a uniform green colour. Life cycle The species overwinters on rose, its primary host, as an egg. On hatching in the spring, rose-grain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sitobion Avenae
The English grain aphid (''Sitobion avenae'') is an aphid in the superfamily Aphidoidea in the order Hemiptera. It is a true bug and sucks sap from plants. It lives on grasses, sedge and rushes and can be a significant pest of cereals. This species act as a host of the entomophthoralean fungi. Parthenogenesis Some genotypes of ''S avenae'' are obligate parthenogens and some are cyclical parthenogens.Dedryver CA, Le Gallic JF, Mahéo F, Simon JC, Dedryver F. The genetics of obligate parthenogenesis in an aphid species and its consequences for the maintenance of alternative reproductive modes. Heredity (Edinb). 2013 Jan;110(1):39-45. doi: 10.1038/hdy.2012.57. Epub 2012 Sep 19. PMID: 22990313; PMCID: PMC3522239 Cyclically parthenogenetic lines can reproduce parthenogenetically in the spring and summer. Production of sexual females and males is induced during autumn by decreasing day length and decreasing temperature. Mating followed by egg laying occurs on grasses ( Poace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizaphis Graminum
The greenbug, or wheat aphid (''Schizaphis graminum''), is an aphid in the superfamily Aphidoidea in the order Hemiptera. It is a true bug and feeds on the leaves of Gramineae (grass) family members. Its original distribution is the Palaearctic, but it has been introduced to other parts of the world. It is one of about 40 recognized ''Schizaphis'' species worldwide. Description Adult greenbugs are long. The head and thorax are straw-colored to pale green and the abdomen is mid-green, with a dark green dorsal stripe in late-stage nymphs and adults. The antennae are dark and the cornicles are pale with dark tips. Early in the season the adults are wingless, but under conditions of over-crowding, winged forms appear and migrate to neighbouring plants. Host plants This aphid feeds almost exclusively on a range of grasses in the family Poaceae; genera attacked include ''Agropyron'', ''Avena'', ''Bromus'', ''Dactylis'', ''Eleusine'', ''Festuca'', '' Hordeum'', '' Lolium'', ''Oryz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhopalosiphum Padi
Bird cherry-oat aphid (''Rhopalosiphum padi'') is an aphid in the superfamily Aphidoidea in the order Hemiptera. It is a true bug and sucks sap from plants. It is considered a major pest in cereal crops, especially in temperate regions, as well as other hosts in parts of Northern Europe. It is the principal vector of many viruses in economically important field crops. Host plants and distribution ''R. padi'' has a worldwide distribution and according to research, they can colonize a number of dicotyledon host plants, although their preference is within monocotyledon plant groups much like the closely related ''Rhopalosiphum maidis, R. maidis'' and ''Rhopalosiphum rufiabdominale, R. rufiabdominale''. The main plant hosts are categorized and listed below but as the name suggests, the primary host is ''Prunus padus'', where it overwinters as eggs. In Northern America, it is found to overwinter on ''Prunus virginiana'' (common choke-cherry). In spring, it attacks all major cereals a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corn Leaf Aphids (Rhopalosiphum Maidis) On Maize (Zea Mays)
Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. The leafy stalk of the plant produces pollen inflorescences (or "tassels") and separate ovuliferous inflorescences called ears that when fertilized yield kernels or seeds, which are fruits. The term ''maize'' is preferred in formal, scientific, and international usage as a common name because it refers specifically to this one grain, unlike ''corn'', which has a complex variety of meanings that vary by context and geographic region. Maize has become a staple food in many parts of the world, with the total production of maize surpassing that of wheat or rice. In addition to being consumed directly by humans (often in the form of masa), maize is also used for corn ethanol, animal feed and other maize products, such as corn starch and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugarcane
Sugarcane or sugar cane is a species of (often hybrid) tall, Perennial plant, perennial grass (in the genus ''Saccharum'', tribe Andropogoneae) that is used for sugar Sugar industry, production. The plants are 2–6 m (6–20 ft) tall with stout, jointed, fibrous stalks that are rich in sucrose, which accumulates in the Plant stem, stalk internodes. Sugarcanes belong to the grass family, Poaceae, an economically important flowering plant family that includes maize, wheat, rice, and sorghum, and many forage crops. It is native to the warm temperate and tropical regions of India, Southeast Asia, and New Guinea. The plant is also grown for biofuel production, especially in Brazil, as the canes can be used directly to produce ethyl alcohol (ethanol). Grown in tropical and subtropical regions, sugarcane is the world's largest crop by production quantity, totaling 1.9 billion tonnes in 2020, with Brazil accounting for 40% of the world total. Sugarcane accounts for 79% of sug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barley
Barley (''Hordeum vulgare''), a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 10,000 years ago. Globally 70% of barley production is used as animal fodder, while 30% as a source of fermentable material for beer and certain distilled beverages, and as a component of various foods. It is used in soups and stews, and in barley bread of various cultures. Barley grains are commonly made into malt in a traditional and ancient method of preparation. In 2017, barley was ranked fourth among grains in quantity produced () behind maize, rice and wheat. Etymology The Old English word for barley was ', which traces back to Proto-Indo-European and is cognate to the Latin word ' "flour" (''see corresponding entries''). The direct ancestor of modern English ''barley'' in Old English was the derived adjective ''bærlic'', meaning "of barley". The first citation of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheat
Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeological record suggests that wheat was first cultivated in the regions of the Fertile Crescent around 9600 BCE. Botanically, the wheat kernel is a type of fruit called a caryopsis. Wheat is grown on more land area than any other food crop (, 2014). World trade in wheat is greater than for all other crops combined. In 2020, world production of wheat was , making it the second most-produced cereal after maize. Since 1960, world production of wheat and other grain crops has tripled and is expected to grow further through the middle of the 21st century. Global demand for wheat is increasing due to the unique viscoelastic and adhesive properties of gluten proteins, which facilitate the production of processed foods, whose consumption is inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cucumber Mosaic Virus
''Cucumber mosaic virus'' (CMV) is a plant pathogenic virus in the family ''Bromoviridae''. This virus has a worldwide distribution and a very wide host range, having the reputation of the widest host range of any known plant virus. It can be transmitted from plant to plant both mechanically by sap and by aphids in a stylet-borne fashion. It can also be transmitted in seeds and by the parasitic weeds, ''Cuscuta sp.'' (dodder). Hosts and symptoms This virus was first characterized in cucumbers (''Cucumis sativus'') showing mosaic symptoms in 1934, hence the name ''Cucumber mosaic''. Since then, it has been found to infect a great variety of other plants. These include other vegetables such as squash, melons, peppers, eggplants,tomatoes, beans, carrots, celery, lettuce, spinach, beets, many ornamentals and bedding plants, such as '' Narcissus'', and various weeds. Its presence has been confirmed on every continent of the world, including Antarctica. Symptoms seen with this virus ... [...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] |
