hybrids and crossbreeds mixed breed dog Heterosis , or hybrid vigor , or outbreeding enhancement , is the improved .... The adjective derived from heterosis is heterotic . Heterosis is the occurrence of a superior offspring ... Mendelian or non Mendelian inheritance . Definitions In proposing the term heterosis to replace ... be explained by heterozygosity in Mendelian inheritance. ref cite journal date 1948 title What Is Heterosis ... heterosis be adopted. Heterosis is the opposite of inbreeding depression . Inbreeding depression leads to offspring with deleterious traits due to Zygosity homozygosity . The term heterosis often ... of heterosis, when a hybrid inherits traits from its parents that are not fully compatible, with deleterious results, is outbreeding depression . Genetic basis of heterosis Main Dominance versus overdominance ... heterosis than F1 hybrids from inbreds within the same heterotic group or pattern. Heterotic groups ... recurrent selection. Heterosis is used to increase yields, uniformity, and vigor. Hybrid breeding ... exhibits heterosis. Modern corn hybrids substantially outyield conventional cultivars and respond better to fertilizer . Corn heterosis was famously demonstrated in the early 20th century by George ... flint, respectively, showed substantial heterosis and outyielded conventional cultivars of that era ... 2011 and non stiff stalk. cn date October 2011 Hybrid livestock The concept of heterosis is also ..., so any evidence of heterosis in humans is derived from observational study observational studies ... effects on average health, intelligence and height have resulted from an increased heterosis, in turn ... heterosis a closer look journal Intelligence year 2004 volume 32 pages 65 83 doi 10.1016 S0160 2896 ... JA, Auger DL, Riddle NC title In Search of the Molecular Basis of Heterosis journal Plant Cell volume .... Category Classical genetics Category Breeding bg ca Heterosi de Heterosis Effekt es Heterosis fr H t rosis id Heterosis it Eterosi he kk nl Heterosis pl Heterozja ... more details
vva Heterosis tables.svg Summary I made this image user seb951 seb951 with Ms Excel. Licensing GFDL self with disclaimers migration relicense Copy to Wikimedia Commons bot Fbot Orphan image ... more details
Cross fertilization can refer to Allogamy , where an ovum from one individual is fertilized with the spermatozoa of another Heterosis , where different strains are cross bred to form a hybrid the union of pollen from the anther of the stamen, with the female gametes of the pistil disambig ... more details
Vigor may refer to wiktionary vigor Biology The ability of an organism to survive and grow Heterosis , the vigor of a hybrid biology hybrid breed People Vigor Bovolenta , Italian volleyball player Saint Vigor d. 537 AD , French saint Places Saint Vigor Saint Vigor le Grand Saint Vigor des M zerets Cars Honda Vigor disambig ja ... more details
Hybrid growth disorders refer to reduced growth or overgrowth in an organism that is a Hybrid biology hybrid of two different species. In some sense, it is a type of hybrid dysgenesis when the growth disorder proves deleterious, thus making it the opposite of heterosis heterosis or hybrid vigour . Hybrid growth disorders may be referred to as a growth dysplasia , especially when resulting in overgrowth, although this terminology may be confusing since the term dysplasia is commonly used to imply an impending cancer. However, a hybrid growth disorder is not caused by cancer. A study on hybrid mice which investigated the possible causes for hybrid growth disorders revealed Imprinting genetics gene imprinting to have a major effect. ref cite journal author Paul B. Vrana et al. title Genetic and epigenetic incompatibilities underlie hybrid dysgenesis in Peromyscus journal Nature Genetics year 2000 volume 25 pages 120 124 doi 10.1038 75518 pmid 10802670 issue 1 ref The study also showed that the growth disorder most commonly affected the heterozygote heterozygous sex, as expected by Haldane s rule . This would also explain why hybrid growth disorders often appear to affect one sex more than the other. See also F1 hybrid References references Category Developmental biology Category Classical genetics genetics stub developmental biology stub ... more details
DISPLAYTITLE Polygonatum hybridum Speciesbox genus Polygonatum species hybrid hybridum image Polygonatum.JPG Polygonatum hybridum Garden Solomon s seal is a hybrid cross between Common Solomon s seal Polygonatum multiflorum and Angular Solomon s seal Polygonatum odoratum . In gardens it is susceptible to attack by the larvae of Soloman s Seal sawfly Phymatocera aterrima , which feed on the underside of the leaves, rapidly reducing them to a skeletonised appearance. The plant tends to be Heterosis more vigorous than either of its parent species. ref The Readers Digest Field Guide to the Wild Flowers of Britain p.376 . ref References reflist Category Nolinoideae Polygonatum hybridum Asparagales stub ar ... more details
merge to Heterosis date October 2011 Dominance versus overdominance is a scientific controversy in the field of genetics that has persisted for more than a century. ref Birchler, J.A. Auger, D.L. Riddle, N.C. 2003 . In search of the molecular basis of heterosis. The Plant Cell . 15 2236 2239. ref These two alternative hypotheses were first stated in 1908. Genetic basis of heterosis When a population is small or inbred, it tends to lose genetic diversity. Inbreeding depression is the loss of fitness due to loss of genetic diversity. Inbred strains tend to be homozygous for recessive alleles that are mildly harmful or produce a trait that is undesirable from the standpoint of the breeder . Heterosis or hybrid vigor, on the other hand, is the tendency of outbred strains to exceed both inbred parents in fitness. Selective breeding of plants and animals, including hybridization, began long before there was an understanding of underlying scientific principles. In the early 20th century, after Mendel s laws came to be understood and accepted, geneticists undertook to explain the superior vigor of many plant hybrids. Two competing hypotheses, which are not mutually exclusive, were developed ref cite journal author James F. Crow Crow, James F. year 1948 journal Genetics title Alternative Hypotheses of Hybrid Vigor volume 33 issue 5 pages 477 487 ref Image Heterosis.svg thumb 300px right Genetic basis of heterosis . Dominance hypothesis . Scenario A . Fewer genes are under expressed in the homozygous individual. Gene expression in the offspring is equal to the expression of the fittest parent. Overdominance hypothesis . Scenario B . Over expression of certain genes in the heterozygous offspring. The size of the circle depicts the expression level of gene A Dominance hypothesis . The dominance hypothesis attributes the superiority of hybrids to the suppression of undesirable recessive ... cause for the fitness advantages of heterosis, then there should be an over expression of certain ... more details
Unreferenced date December 2009 In agriculture and gardening , hybrid seed is seed produced by pollination cross pollinated plant s. In hybrid seed production, the crosses are specific and controlled. The advantage of growing hybrid seed compared to inbred lines comes from heterosis . To produce hybrid seed, elite inbred varieties with well documented and consistent phenotypes such as yield are crossed and the resulting hybrid seed is collected. Another factor that is important in hybrid seed production is the combining ability of the parent plants. Although two elite inbred parent plant varieties may produce the highest yields of their crop, it does not necessarily mean that crossing these inbreds will result in the highest yielding hybrid. Combining ability is the term used to describe the level of heterosis that the parents will generate in the resultant seed. Higher combining ability between the parents results in increased performance in the resulting hybrid seed. Hybrids are bred to improve the characteristics of the resulting plants, such as better crop yield yield , greater uniformity, improved color , disease resistance, and so forth. Today, hybrid seed production is predominant in agriculture and home gardening, and is one of the main contributing factors to the dramatic rise in agricultural output during the last half of the 20th century. In the US, the commercial market was launched in the 1920s, with the first hybrid maize . All of the hybrid seeds planted by the farmer will be the same hybrid, which causes the first generation of seed from the hybrids planted to be inbred. This is why hybrid seed is generally not saved from subsequent generations and is purchased for each planting. Hybrid seeds are much dearer than normal seeds, due to the technology, time and effort put in to produce them. See also hybrid biology open pollination plant breeding seed saving Sterile male plant External links http www.seedconsortium.org PUC pdf 20files 23 Vegetable 20Hyb ... more details
About string theory heterosis in biology Heterosis Refimprove date December 2009 Technical date January 2010 String theory cTopic Theory In physics , a heterotic string is a peculiar mixture or hybrid of the bosonic string theory bosonic string and the superstring the adjective heterotic comes from the Greek word heterosis , hybrid vigour . In string theory , the left moving and the right moving excitations almost do not interact with each other, and it is possible to construct a string theory whose left moving counter clockwise excitations think that they live on a bosonic string propagating in D 26 dimensions, while the right moving clock wise excitations think that they belong to a superstring in D 10 dimensions. The mismatched 16 dimensions must be compactified on an even, self dual lattice a discrete subgroup of a linear space . There are two possible even self dual lattices in 16 dimensions, and it leads to two types of the heterotic string. They differ by the gauge group in 10 dimensions. One gauge group is special orthogonal group SO 32 the HO string while the other is E8 mathematics E sub 8 sub × E sub 8 sub the HE string . These two gauge groups also turned out to be the only two anomaly physics anomaly free gauge groups that can be coupled to the N 1 supergravity in 10 dimensions other than U 1 sup 496 sup and E sub 8 sub × U 1 sup 248 sup , which is suspected to lie in the Swampland physics swampland . Heterotic string theory was first developed in 1985 by David Gross , Jeffrey Harvey , Emil Martinec , and Ryan Rohm the so called Princeton String Quartet ref http www.nytimes.com 2004 12 07 science 07stri.html?pagewanted 2&fta y NY Times ref , in one of the key papers that fueled the first superstring revolution . A year later in 1986, Strominger derived the Strominger s equations which are the necessary and sufficient conditions for spacetime supersymmetry. In the 1990s, it was realized ... more details
Unreferenced stub auto yes date December 2009 Intraspecific breeding is the act of breeding two variety biology varieties within the same species . The breeding of intraspecific organisms produce Hybrid biology hybrids that often show hybrid vigour heterosis , growing more vigorously and yielding more than in bred lines. Intraspecific offspring are usually fertile , but will not breed true , although they share the same gene pool . Intraspecific interactions do not generally lead to the extinction of a species although their offspring will be highly variable, some resembling one parent, some the other, and others showing a whole range of characteristics and combinations between the two. Intraspecific offspring, should not be confused with Interspecific hybrids Interspecific hybrids interspecific hybrids such as the mule which are generally not Fertility fertile . In natural environments, intraspecific organisms are much more likely to show pronounced territorial and aggressive behaviour in competition for resources, compared with interspecific organisms. See also Reproduction Breeding Hybrid biology DEFAULTSORT Intraspecific Breeding Category Reproduction Biology stub ... more details
The Effects of Cross and Self Fertilisation in the Vegetable Kingdom is a book on evolution in plants by Charles Darwin , first published in 1876. In this book Darwin examines the effects of heterosis cross and self pollination self fertilisation of plants and provides experimental evidence for a hypothesis stated in his famed book of 1859, Origin of Species , that ... in none i.e. plant ... can self fertilisation go on for perpetuity Origin , p. 101 . He reports on experiments conducted on over 60 different species of plants, where he used controlled pollinations in order to produce self fertilised and cross fertilised descendants. Through growth experiments of this progeny, he concluded that self fertilised progeny performed poorer in most species and for most traits measured. Thus he showed that inbreeding may have severe detrimental effects on progeny. While this idea was accepted by many, e.g. plant and animal breeders, Darwin s book provided overwhelming experimental support for this idea. This book has remained the starting point for the study of inbreeding and is cited in scientific papers to this effect to this day. References http charles darwin.classic literature.co.uk the effects of cross and self fertilisation e book at Classic Literature Library DEFAULTSORT Effects of Cross and Self Fertilisation in the Vegetable Kingdom, The Category 1876 books Category Books by Charles Darwin Category 1870s in science Category 1876 in science ... more details
models for assessing the influence of epistasis on heterosis. Last but not least, he modernized ... included modelling epistasis in the presence of linkage, quantitative genetic interpretation of heterosis ... quantitative genetic theory of heterosis . In several papers and scientific talks he made ... 1992 he clarified the influence of multiplicative gene action versus other types of epistasis in heterosis ... Honorary title Distinguished Pioneer in Heterosis granted by the International Center of Maize and Wheat ... in heterosis. Genetics 131 461 469. References Melchinger AE 1998 Prof. Dr. Dr. h. c. F. Wolfgang ... more details
Image potato leaf.jpg thumb right 220px Image of a brandywine tomato brandywine tomato plant, showing the smooth potato leaves Image Tomato scanned.jpg thumb right Normal tomato leaves, not potato style. Potato leaf , or PL , is one of two major types of leaves which tomato plants exhibit. The other type is referred to as regular leaf, or RL. Simply stated, potato leaf tomato plants have a smooth leaf edge ref name gardenweb Cite web last first authorlink title Are there different types of tomato leaves? work GardenWeb publisher date url http faq.gardenweb.com faq lists tomato 2004111539004321.html doi accessdate 2010 07 20 ref when compared with the serrated edge of the regular leaf. The shape is oval and may feature notches separating large lobes. ref name gardenweb Its color is dark green. ref name gardenweb Examples of potato leaf tomatoes include the Brandywine tomato Brandywine , List of heirloom tomato cultivars Common cultivars Prudens Purple , Brandy Boy, Heirloom tomato Cultivars Lillian s Yellow Heirloom , ref name gardenweb List of heirloom tomato cultivars Common cultivars Stupice and others. The potato leaf trait is recessive. ref Cite book last Rai first Nagenda authorlink coauthors Mathura Rai title Heterosis Breeding in Vegetable Crops publisher New India Publishing Agency year 2006 location New Delhi url doi id isbn 81 89422 03 0 page 265 ref Notes Reflist DEFAULTSORT Potato Leaf Category Tomatoes Category Leaves Horticulture stub ... more details
refimprove date September 2011 About hybrid chickens the biologic principles of sex linked inheritance Sex linkage Image Midnight1101.jpg thumb 250px A black sex link hen Sex links are crossbreeding cross bred chicken s whose color at hatching is differentiated by sex, thus making chick sexing an easier process. Sex links come in many varieties, few of which are a true breed . As hybrids of laying or dual purpose breeds infused with extra vigor via heterosis , sex links can be extremely good egg layers which often produce 300 eggs a year or more depending on the quality of care and feed. Two common varieties are the Black sex link also called Black Stars and the Red sex link also called Red Stars . Blacks are a cross between a Rhode Island Red or New Hampshire chicken New Hampshire rooster and a Barred Rock hen. Red sex links are a cross between a Rhode Island Red or New Hampshire rooster and a White Rock chicken White Rock , Wyandotte chicken Silver Laced Wyandotte , Rhode Island White or Delaware chicken Delaware hen. One example of a red linked breed is the Red Shaver . In Europe, the Cream Legbar an actual true breeding pure breed and ISA Brown sex links also exist. Gallery gallery File Black Rock Hen Blackie .jpg A Black Rock hen File RedStarhen.jpg A red sex link pullet File Beautiful Roo by sejr.jpg A black sex link rooster Harry File Shipped pullets.jpg Shipped pullets File LindaLeePrintSmallerIISHY.jpg Red sex link hen Linda Lee gallery See also Commons Category Sex Link Sex link List of chicken breeds References reflist Category Chicken hybrids ... more details
Orphan date February 2009 Image CornhengeDublinOhio.jpg thumb Concrete Corn Cornhenge is a slang reference to a publicly funded art installation in the city of Dublin, Ohio Dublin , Ohio . The installation, officially named Field of Corn with Osage Orange Trees , consists of 109 concrete ears of Maize corn positioned in rows and standing upright in a grassy field. At one end of the field are two rows of Osage orange trees, one pre existing and the other planted for the project. Sculpted by Malcolm Cochran ref David Raskin Malcolm Cochran at the Cleveland Center for Contemporary Art Brief Article. Art in America. FindArticles.com. Accessed 1 April 2009. http findarticles.com p articles mi m1248 is 5 88 ai 62111818 ref and with landscaping by Stephen Drown and James Hiss, the field of corn was commissioned by the Dublin Arts Council and completed in 1994. ref Greenmuseum.org, 2006, accessed 1 April 2009 http www.greenmuseum.org c aen Issues cochran.php ref The display site, named the Sam and Eulalia Frantz Park, was originally farmed by Sam Frantz , an inventor of several Hybrid biology hybrid corn species, and was donated to the city in the late twentieth century. The art installation is partly a tribute to Sam Frantz and is also intended to remind visitors of Dublin s agricultural heritage. Along the west side of the park, near the Osage orange trees, are signs that describe the project and explain hybridization. Three different molds were used to cast the concrete ears of corn, which stand about convert 8 ft m 0 tall. The breed of corn represented is known as Corn Belt Dent Corn , a Heterosis Hybrid corn double cross hybrid variety. Soon after completion, the art installation became a target for criticism, joking, and creative pranks, such as painting portions of the sculptures. Due to its odd setting in the shadow of business parks, and having been funded by tax money, the display was given the nickname Cornhenge by the public. References references coord missing ... more details
breeds through the Dominance versus overdominance genetic heterosis created by combining ... genetic benefit if it is an F1 hybrid . ref name AM A crossbred animal is likely to enjoy heterosis ... more details
Open pollination is pollination by Insect Roles in the environment and human society insects , Bird Ecology birds , wind , or other nature natural mechanisms, and contrasts with cleistogamy , closed pollination, which is one of the many types of self pollination ref Kearns, C.A. Inouye, D.W. 1993. Techniques for pollination biologists. University Press of Colorado, Niwot, CO. ref . Open pollination also contrasts with controlled pollination, which is controlled so that all seeds of a crop are descended from parents with known traits, and are therefore more likely to have the desired traits. The seed s of open pollinated plant s will produce new generation s of those plants however, because breeding is uncontrolled and the pollen male parent source is unknown, open pollination may result in plants that vary widely in genetics genetic traits. Open pollination may increase biodiversity . Some plants such as many crops are primarily self pollenizer pollenizing and also True breeding organism breed true , so that even under open pollination conditions the next generation will be almost the same. Even among true breeding organisms, some variation due to genetic recombination or to mutation can produce a few off types . Hybrid pollination, a type of controlled pollination in which the pollen comes from a different Strain biology strain or species , can be used to increase suitability, especially through heterosis . The resulting hybrid strain can sometimes be inbreeding inbred and selected for desired traits until a strain that breeds true by open pollination can be developed. The result may be referred to as a hybrid inbred or inbred hybrid strain. To add some confusion, the term hybrid inbred also applies to hybrids that are made from selected inbred lines that have certain desired characteristics see inbreeding . Such hybrids are sometimes designated F1 hybrid , i.e. the first hybrid filial generation whose parents were different inbred plants. One of the bigger challen ... more details
Allogamy cross fertilization is a term used in the field of biological reproduction describing the fertilization of an ovum from one individual with the spermatozoa of another. By contrast, autogamy is the term used for self fertilization. In humans, the fertilization event is an instance of allogamy. Self fertilization also known as autogamy occurs in hermaphrodite hermaphroditic organisms where the two gamete s fused in fertilization come from the same individual. This is common in plant s see Sexual reproduction in plants and certain protozoa ns. In plants, allogamy is used specifically to mean the use of pollen from one plant to fertilize the flower of another plant and usually synonymous with the term cross fertilization or cross pollination , though the latter term can be used more specifically to mean pollen exchange between different Strain biology plant strains or even different plant species where the term cross hybridization can be used rather than simply between different individuals. Parasite s having complex Biological life cycle life cycles can pass through alternate stages of allogamous and autogamous reproduction, and the description of a hitherto unknown allogamous stage can be a significant finding with implications for human disease. See also Heterosis References Reflist cite web url http www.genetics.org cgi content abstract 168 3 1563 title High Resolution Mapping and Functional Analysis of se2.1 A Major Stigma Exsertion Quantitative Trait Locus Associated With the Evolution From Allogamy to Autogamy in the Genus Lycopersicon 168 3 1563 Genetics publisher www.genetics.org accessdate 2009 08 08 last Kai Yi Chen first Steven D. Tanksley cite web url http rparticle.web p.cisti.nrc.ca rparticle AbstractTemplateServlet?calyLang eng&journal cjb&volume 50&year 1972&issue 8&msno b72 219 title Autogamy, allogamy, and pollination in some Canadian weeds Can. J. Bot. 50 8 1767 1771 1972 publisher rparticle.web p.cisti.nrc.ca accessdate 2009 08 08 last Mull ... more details
In sheep farming, the term Mule is used to refer to a cross between a lowland ram animal ram usually a Bluefaced Leicester and a purebred Highland geography upland or hill ewe. ref cite web url http www.mulesheep.com title Three tier Breeding Scheme publisher North American Mule Sheep Society ref The production of such mule ewes is a widely used breeding management system which offers several advantages to the farmer. Cross breeding the hill ewe with the lowland ram brings about hybrid vigour or heterosis, which brings the best characteristics of both breeds into one ewe that can be used in producing lamb for the table. The hill ewe, for example the Scottish Blackface , is a hardy animal with good, natural mothering instincts. She is, however, not very prolific and tends to produce one lamb suited to the harsh conditions. The lowland ram, such as the Blueface Leicester is prolific, producing ewes which give 1 3 lambs and capable of producing enough milk to rear them. The cross between the two, in this case the Scottish mule, has good mothering instincts, good sized lambs and prolific milk production. This mule is usually crossed with a meat type ram, such as the Suffolk sheep Suffolk or Texel sheep Texel , to produce these market lambs. This breeding also allows a convenient system of management whereby hill ewes can be reared in difficult areas where other species would not survive to produce lamb. At the end of her productive life around 4 years she can be moved to a lowland farm and crossed with the Blueface Leicester or a similar breed to produce the mules for market lamb production. Types of mules North of England or North Country Mule a mule with a Swaledale sheep Swaledale dam. This is by far the most common type of mule. Scotch Mule a mule with a Scottish Blackface dam. Welsh Mule a mule with a Welsh Mountain sheep Welsh Mountain , Beulah or Welsh Hill Speckled face dam. Clun Mule a mule with a Clun Forest sheep Clun Forest dam. Cheviot Mule a mule with a Ch ... more details
About the colour variety of the Hereford cattle breed the hybrid type Black Hereford hybrid More references date October 2010 Advert date October 2010 The Black Hereford is a beef cattle breed, derived mainly from Hereford cattle normally red and white , but with some mixture from black Angus cattle , resulting in black cattle with a white head and finching cattle finching . Characteristics Like red Herefords, Black Herefords are becoming known for their feed efficiency and docile temperament. If a registered Black Hereford is crossed with a registered red Hereford and the resulting progeny is black, then it may be registered with the Black Hereford Association. The Black Hereford breed was formed to create cattle that would pass on the desirable traits of the red Hereford, but with black and white coloring. Like red Herefords, Black Herefords are often crossed with black Angus cattle to produce heterosis hybrid vigor in the progeny, producing a type commonly known as the Black Baldy . History The American Black Hereford Association was established as a non profit corporation in 1994, by the late John Gage. The first Black Herefords to qualify for registration were recorded in 1997. In 2003 the Black Hereford received international breed designation by the National Association of Animal Breeds. In 2005 the American Black Hereford Association implemented its own EPDs. Clarify date October 2010 reason What is EPD ? Now there are breeders throughout the United States. ref name ABHA http www.blackhereford.com American Black Hereford Association ref Uses Many cattle breeders desire the traits of the red Hereford cattle, but want black cattle. Clarify date October 2010 reason Why? Also, many breeders want to introduce Hereford type traits into their black cattle while maintaining the black color. The Black Hereford allows breeders to accomplish both of these goals. The Black Hereford is an efficient, docile cattle breed used mainly to produce beef. Similar types Black Her ... more details
promotes improved growth and yield characteristics in the F1 offspring through the phenomenon of heterosis ... to in genetics as heterosis . F1 hybrids can give higher yields than traditional varieties ... a longer period of time, avoiding gluts and food shortages. See also Heterosis hybrid vigour Genetics ... more details
heterosis in maize in 1908 and made a number of other key discoveries in emerging field of genetics ... of the process of heterosis is in the movie High Time starring Bing Crosby about a wealthy man going ... s character asks Who discovered the process of heterosis? to which the young student answers George ... more details
work in cross breeding. In 1908, George Harrison Shull described heterosis , also known as hybrid vigor. Heterosis describes the tendency of the progeny of a specific cross to outperform both parents ... reflist Citation surname Basra given Amarjit S. year 1999 title Heterosis and Hybrid Seed ... more details
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