processes in animal s and Oomycetes , see Parthenogenesis . In botany , apomixis was defined by Hans ..., has never been considered to be apomixis, but replacement of the seed by a plantlet , or replacement of the flower by bulbils are types of apomixis. Apomictically produced offspring are genetically identical to the parent plant. In flowering plants, the term apomixis is commonly used in a restricted ... is still used interchangeably with apomixis , and both refer to the formation of sporophytes by parthenogenesis of gametophyte cells. See also Male apomixis in a conifer below. Apomixis and evolution ... agg. . In some Family biology plant families , genera with apomixis are quite common, e.g. in Asteraceae , Poaceae , and Rosaceae . Examples of apomixis can be found in the genera Crataegus ... of sexual reproduction are lost, apomixis can pass along traits fortuitous for evolutionary fitness. As Clausen eloquence eloquently put it ref Clausen, J. 1954 . Partial apomixis as an equilibrium .... ... Facultative apomixis ... does not prevent variation rather, it multiplies certain varietal products. Facultative apomixis means that apomixis does not always occur, i.e. sexual reproduction also can happen. It appears likely ref name Savidan Savidan, Y.H. 2000 . Apomixis genetics and breeding. 18 Plant Breeding Reviews 13 86. ref that in plants all apomixis is facultative, i.e. that obligate apomixis is an artifact of the observation methods. B cher ref B cher TW. 1951. Cytological ... plants increased sexual seed set under stress conditions. Apomixis in non flowering plants Expand section date July 2011 Apospory in ferns Apomixis in flowering plants angiosperms Agamospermy, asexual .... Consequently there are almost as many different usages of terminology for apomixis in angiosperms .... Agamospermy occurs mainly in two forms In gametophytic apomixis , the embryo arises from an unfertilized ... meiosis . In adventitious embryony sporophytic apomixis , an embryo is formed directly not from ... more details
of the term ref Hermsen, J.G.T. 1980 . Breeding for apomixis in potato Pursuing a utopian .... Apomixis in the angiosperms. In Handbuch der Pflanzenphysiologie. Edited by W. Ruhland. Springer Verlag, Berlin. pp. 551 596. ref ref name Nogler Nogler, G.A. 1984. Gametophytic apomixis. In Embryology ... apomixis, below . A better term for the restrictive sense is centrogamy ref Solntzeva, M.P. 2003 . About some terms of apomixis pseudogamy and androgenesis. Biologia . 58 1 1 7. ref . Pseudogamous apomixisApomixis in flowering plants angiosperms includes some types of vegetative reproduction and also ... und Apogamie im Pflanzenreich. Progressus Rei Botanicae . 2 3 293 454. ref see apomixis for more ... , some of which require pollination pseudogamy , and some which do not autonomous apomixis . Many flowering plants with pseudogamous apomixis require fertilization to produce the endosperm of the seed ... endosperm development is autonomous. Pseudogamous apomixis occurs in many Family biology families ... in many different genera and species . Examples of species with pseudogamous apomixis include the Himalayan blackberry Rubus armeniacus and gamagrass Tripsacum dactyloides . Autonomous apomixis is the rule ... . Species with autonomous apomixis include the common dandelion Taraxacum officinale . References ... more details
Cytomixis originally called cytomyxis ref name Gates Gates, R.R. 1911 . Pollen formation in 0enothera gigas . Annals of Botany . 25 909 940. ref is a process of chromosome transfer that can occur during pollen formation in flowering plants. It results in pollen grains with chromosome numbers greater or less than the haploid number, possibly including some that are diploid or polyploid, and often producing some non viable pollen grains. During cytomixis there is, at least in some flowers but probably not in all, an extrusion of chromatin from the Cell nucleus nucleus of one pollen mother cell through cytoplasmic connections, into the cytoplasm of an adjacent mother cell. ref name Gates Cells may also fuse completely. The phenomenon appears to have a genetic component. ref Omara, M.K. 1976 . Cytomixis in Lolium perenne . Chromosoma . 55 3 267 271. ref Diploid or polyploid pollen grains produced by cytomixis may have a significant role in evolution. ref Falistocco, E. Tosti, N. Falcinelli, M. 1995 . Cytomixis in pollen mother cells of diploid Dactylis , one of the origins of 2 n gametes. Journal of Heredity . 86 6 448 453. ref See also Apomixis in flowering plants various processes that occur in the gynoecium , some of which involve doubling the chromosome number. Parthenogenesis , the animal equivalent of apomixis. References reflist Category Plant reproduction ... more details
italic title Taxobox name Meloidogyne javanica regnum Animal ia phylum Nematoda classis Secernentea subclassis Diplogasteria ordo Tylenchida superfamilia Tylenchoidea familia Heteroderidae subfamilia Meloidogyninae genus Meloidogyne species M. javanica binomial Meloidogyne javanica binomial authority Meloidogyne javanica is a plant pathogenic nematode. It is one of the tropical Root knot nematode root knot nematodes and a major agricultural pest in many countries. Meloidogyne javanica reproduces by obligatory mitotic parthenogenesis apomixis . External links http plpnemweb.ucdavis.edu Nemaplex Taxadata g076s4.htm Nemaplex, University of California Meloidogyne javanica Category Nematodes Category Plant pathogens and diseases nematode stub plant disease stub ... more details
Taxobox image Cupressus atlantica1.jpg status EN status system iucn2.3 status ref ref IUCN2009.2 assessors Anonymous year 2000 title Cupressus dupreziana var. atlantica id 44045 downloaded February 1, 2010 ref regnum Plant ae divisio Pinophyta classis Pinophyta Pinopsida ordo Pinales familia Cupressaceae genus Cupressus species C. atlantica binomial Cupressus atlantica binomial authority Henri Marcel Gaussen Gaussen synonyms C. dupreziana var. atlantica small Gaussen John Silba Silba small Cupressus atlantica , the Moroccan Cypress , is a rare Pinophyta coniferous tree endemic ecology endemic to the valley of the Oued n Fiss river in the Atlas Mountains High Atlas Mountains south of Marrakech in western Morocco . The majority are old, with very little regeneration due to overgrazing by goat s. This species is distinct from the allied Cupressus sempervirens Mediterranean Cypress in its much bluer foliage with a white resin spot on each leaf , the smaller shoots often being flattened in a single plane. It also has smaller, globose conifer cone cones , only 1.5 2.5 cm long. Cupressus dupreziana Saharan Cypress is more similar, and C. atlantica is treated as a variety of it C. dupreziana var. atlantica by some authors. Moroccan Cypress does not however share the unique reproductive system of apomixis male apomixis found in Saharan Cypress. References reflist External links http www.conifers.org cu cup atlantica.htm Gymnosperm Database Cupressus atlantica Category Cupressus atlantica Category Trees of Morocco Category Flora of Northern Africa Category Plants described in 1950 Category Endemic flora Category Endangered plants conifer stub ar ca Xiprer del Marroc de Atlas Zypresse es Cupressus atlantica eo Atlasa cipreso fr Cypr s du Maroc no Marokkansk sypress sk Cyprus atlask ... more details
Image Citrus fruits.jpg thumb Most commercial citrus varieties produce mainly nucellar seedlings. Nucellar embryony notated Nu is a form of seed reproduction that occurs in certain plant species, including many citrus varieties. During the development of seeds from plants that possess this genetic Trait biology trait , the nucellar tissue which surrounds the megagametophyte can produce additional embryos polyembryony which are genetically identical to the parent plant. These nucellar seedlings are essentially Cloning clone s of the parent. By contrast, Zygote zygotic seedlings are sexually produced and inherit DNA genetic material from both parents. Nucellar embryony is important to the citrus industry, as it allows for the production of uniform rootstock which yields consistent results in fruit production. However, this trait can interfere with progress in cross breeding most commercial Grafting scion varieties produce mainly nucellar seedlings which do not inherit any of the traits of the father plant. See also Apomixis References Notes reflist Bibliography External links cite conference first Mikeal L. last Roose title Molecular Genetic Analysis of Nucellar Embryony in Citrus booktitle Citrus Research Board 2000 Annual Report url http www.citrusresearch.com documents c7a4fcdf c23a 4742 8992 d1303b4c636b.PDF accessdate 2006 10 26 cite conference first Joseph L. last Kepiro coauthors Mikeal L. Roose title Molecular Genetic Analysis of Nucellar Embryony Apomixis in Citrus Maximus x Poncirus Trifoliata Using AFLP booktitle Plant & Animal Genomes XI Conference. January 11 15, 2003, Town & Country Convention Center, San Diego, CA url http www.intl pag.org 11 abstracts W23 W161 XI.html accessdate 2006 10 26 Category Tropical agriculture Category Citrus Category Plant reproduction ... more details
Arrhenotoky or arrhenotokous parthenogenesis is a form of parthenogenesis in which unfertilized ovum egg s develop into haploid males. This form is observed in some marine invertebrate s, beetle s, scorpion s, mite s, bee s, etc. For some invertebrates it is a form of sex determination males are produced parthenogenetically, while diploid females are produced biparentally from fertilized eggs. In the case of the honeybee, the queen stores sperm and can lay both fertilized and unfertilized eggs. The unfertilized eggs developed into haploid Drone bee drones by arrhenotoky. See also thelytoky apomixis Haplodiploid sex determination system References cite journal author Roger I. C. Hansell coauthors Margaret M. Mollison William L. Putman title A cytological demonstration of arrhenotoky in three mites of the family Phytoseiidae journal Chromosoma publisher Springer Berlin Heidelberg issn 0009 5915 volume 15 issue 5 year 1964 doi 10.1007 BF00319990 pages 562 7 month Jan Category Reproduction ... more details
very often these hybrids are Apomixis apomictic self fertile without pollination , so able to reproduce clonally from seed without any variation. This has led to a very large number of Apomixis microspecies ... more details
A polyploid complex is a group of interrelated and interbreeding plants that also have differing levels of ploidy that can allow genetic exchange s between unrelated species. The polyploid complex was first described by E. B. Babcock and G. Ledyard Stebbins in their 1938 monograph The American Species of Crepis their interrelationships and distribution as affected by polyploidy and apomixis . In Crepis and some other herbaceous perennial species, a polyploid complex may arise where there are at least 2 genetically isolated diploid populations, in addition to auto and allopolyploid derivatives that coexist and interbreed Hybrid biology hybridise . Thus a complex network of interrelated forms may exist where the polyploid forms allow for genetic exchange between the diploid species that are otherwise unable to breed. ref Stebbins, G. L., Jr. 1940. The significance of polyploidy in plant evolution. The American Naturalist 74 54 66 ref A polyploid complex has also been well described in Glycine plant Glycine . ref Doyle, J. J. 1999. Origins, colonization, and lineage recombination in a widespread perennial soybean polyploid complex. PNAS 96 10741 10745 ref This complex situation does not fit well within the biological species concept of Ernst Mayr which defines a species as groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups . References references Category Genetics Category Evolutionary biology es Complejo poliploide hu Poliploid komplex ... more details
Callose is a plant polysaccharide . It is composed of glucose residues linked together through 1,3 linkages, and is termed a beta glucan &beta glucan . It is thought to be manufactured at the plant cell wall cell wall by callose synthases and is degraded by 1,3 glucanase s. It is laid down at plasmodesmata , at the cell plate during cytokinesis and during pollen development. It is produced in response to wounding, infection by pathogens, aluminium and abscisic acid . Deposits often appear on the sieve plates at the end of the growing season. ref Bell, Peter and Hemsley, Alan 2000 Green Plants Their Origin and Diversity 2nd ed. ISBN 0 521 64109 8 ref Callose also forms immediately around the developing meiocyte s and tetrads of sexually reproducing angiosperm s but is not found in related apomixis apomictic taxa. ref Carman J.G., Crane C.F., Riera Lizarazu O. 1991. Comparative Histology of Cell Walls during Meiotic and Apomeiotic Megasporogenesis in Two Hexaploid Australasian Elymus Species. Crop Science 31 1527 1532 ref See also Curdlan References reflist Category Polysaccharides biochem stub de Callose eo Kalozo it Callosio ja ... more details
Taxobox image Ranunculus auricomus.jpg regnum Plant ae divisio Flowering plant Magnoliophyta classis Magnoliopsida ordo Ranunculales familia Ranunculaceae genus Ranunculus subgenus Ranunculus subgenus Ranunculus R. subg. Ranunculus species R. auricomus binomial Ranunculus auricomus binomial authority Carl Linnaeus L. Ranunculus auricomus , known as Goldilocks Buttercup , ref name Stace cite book title New Flora of the British Isles last Stace first Clive A. authorlink Clive A. Stace year 2010 publisher Cambridge University Press isbn 978 0 521 70772 5 chapter Ranunculus L. Buttercups pages 110 119 ref is a perennial species of buttercup native to temperate Eurasia . It is a calcicole typically found in moist woods and at the margins of woods. It is Apomixis apomictic , and several hundred agamospecies have been recognised. ref name Stace The stem leaves are few and deeply divided giving the plant a filiform appearance. Petals fall easily or may not be present. References references External links Commons category inline Ranunculus auricomus Ranunculus auricomus Category Ranunculus auricomus Category Plants described in 1753 Ranunculales stub az Ranunculus auricomus de Gold Hahnenfu et Kuldtulikas fr Renoncule t te d or it Ranunculus auricomus lv Zeltain gundega lt Auksakuodis v drynas nl Gulden boterbloem pl Jaskier r nolistny ru fi Kev tleinikki sv Majsm rblomma ... more details
Unreferenced stub auto yes date December 2009 This article is about form in botany. For the use in zoology, see Form zoology . In botanical nomenclature , a form forma , plural formae is one of the secondary taxonomic rank s, below that of Variety biology variety , which in turn is below that of species it is an infraspecific taxon. If more than three ranks are listed in describing a taxon, the classification is being specified, but only three parts make up the name of the taxon a genus name, a specific name botany specific epithet , and an infraspecific epithet . The abbreviation f. or the full forma should be put before the infraspecific epithet to indicate the rank. For example Acanthocalycium spiniflorum f. klimpelianum or Acanthocalycium spiniflorum forma klimpelianum Weidlich & Werderm. Donald Crataegus aestivalis Walter Torr. & A.Gray var. cerasoides Sarg. f. luculenta Sarg. is a classification of a plant whose name is Crataegus aestivalis Walter Torr. & A.Gray f. luculenta Sarg. A form usually designates a group with a noticeable but minor deviation. For instance, white flowered forms of species that usually have coloured flowers can be named a f. alba . Formae apomicticae are sometimes named among plants that reproduce asexually, by apomixis . Some botanists believe that there is no need to name forms, since there are theoretically countless numbers of forms based on minor genetic differences. See also Trinomial nomenclature Variety botany Subvariety Variety plant Cultivar Hybrid biology Race biology Taxonomic ranks DEFAULTSORT Form Botany Category Botanical nomenclature Form Category Plant taxonomy 1rank28 Botany stub es Forma bot nica fr Forme botanique hu Alak rendszertan mt Forma botanika nl Vorm biologie tr Form botanik ... more details
Ernest Brown Babcock July 10, 1877 December 8, 1954 was an United States plant geneticist who pioneered the understanding of plant evolution in terms of genetics. ref cite journal author Smocovitis, V.B. year 2009 title The Plant Drosophila E. B. Babcock, the genus Crepis , and the evolution of a genetics research program at Berkeley, 1915 1947 journal Historical Studies in the Natural Sciences volume 39 issue 3 pages 300 355 url http www.ncbi.nlm.nih.gov pubmed 20077617 ref He is particularly known for seeking to understand by field investigations and extensive experiments, the entire polyploid apomixis apomictic genus Crepis , in which he recognize 196 species. ref cite web year 1958 title Ernest Brown Babcock, 1877 1954 A biographical memoir url http www.nasonline.org publications biographical memoirs memoir pdfs babcock ernest.pdf author George Ledyard Stebbins publisher National Academy of Sciences ref In his career he published more than 100 articles and books explaining plant genetics, including the seminal textbook with Roy Elwood Clausen Genetics in relation to agriculture . ref cite book author Babcock, E.B. Clausen, R.E. year 1918 title Genetics in relation to agriculture publisher McGraw Hill url http books.google.ca books?id xvcYAAAAYAAJ ref botanist Babc. Babcock, E. B. References references Carey, C.W. 2000. Babcock, Ernest Brown. American National Biography Online. Oxford University Press External links worldcat id id lccn n90 614391 Persondata Metadata see Wikipedia Persondata . NAME Babcock, E. B. ALTERNATIVE NAMES SHORT DESCRIPTION DATE OF BIRTH July 10, 1877 PLACE OF BIRTH DATE OF DEATH December 8, 1954 PLACE OF DEATH DEFAULTSORT Babcock, E. B. Category 1877 births Category 1954 deaths Category American geneticists US biologist stub Geneticist stub es Ernest Brown Babcock pt E. B. Babcock ... more details
italic title taxobox image Danthonia intermedia.jpg regnum Plantae unranked divisio Angiosperms unranked classis Monocots unranked ordo Commelinids ordo Poales familia Poaceae genus Danthonia species D. intermedia binomial Danthonia intermedia binomial authority George Vasey botanist Vasey synonyms Danthonia canadensis Danthonia intermedia is a species of Poaceae grass known by the common names timber oatgrass and intermediate oatgrass . This clumping erect perennial grass is native to North America, where it is widespread across most of Canada and along the western United States into California . It is a plant of the plains as well as forested, mountainous, alpine environments. The bunchgrass reaches about half a meter in height at maximum. Its leaves are short and mostly basal. Each inflorescence is a narrow cluster of up to about ten raceme spikelets , each spikelet holding 3 to 6 florets. The flowers are cleistogamy cleistogamous , meaning they remain closed and pollinate themselves. This grass also sometimes undergoes apomixis , reproduction without fertilization. This independence of the need for pollination between individuals is one reason why this grass is so widespread and able to tolerate a variety of climates. This is a desirable grass for grazing land because it begins growing earlier in the spring than most other grasses, and it tolerates heavy grazing better than some other grasses because of its basal meristem , that is, new growth occurs low on the grass instead of on the tip where it can be chewed off. This grass is an indicator of Climax vegetation ecological climax in many ecosystems. External links http ucjeps.berkeley.edu cgi bin get JM treatment.pl?8738,8929,8933 Jepson Manual Treatment http plants.usda.gov java profile?symbol DAIN USDA Plants Profile http www.fs.fed.us database feis plants graminoid danint all.html Ecology http herbarium.usu.edu webmanual info2.asp?name Danthonia intermedia&type treatment Grass Manual Treatment Category Danth ... more details
Taxobox image Cheilanthes feei 1.jpg image width 260px status G5 status system TNC regnum Plant ae divisio Pteridophyta classis Polypodiopsida ordo Polypodiales familia Pteridaceae genus Cheilanthes species C. feei binomial Cheilanthes feei binomial authority Thomas Moore botanist T.Moore Cheilanthes feei is a species of Cheilanthes lip fern known by the common name Slender lip fern . It is native to much of western North America from British Columbia and Alberta to northern Mexico , and throughout much of the central United States. It is found in rocky areas, especially in calcareous rock like limestone where it grows in cracks and crevices. Description File BB 0080 Cheilanthes feei.png thumb left 200px Cheilanthes feei File Cheilanthes feei 4.jpg thumb left 200px Cheilanthes feei gray leaves. This fern bears gray to pale green leaves up to 18 or 20 centimeters long and 3 wide. Each leaflet on the leaf is divided into lobes which are divided once more into rounded segments. The undersides of the segments are concave and densely hairy. The Sorus sori line the edges of the segment undersides and may be buried under the hairs. The fern reproduces asexually by Apomixis apogamy . External links commonscat Cheilanthes feei http ucjeps.berkeley.edu cgi bin get JM treatment.pl?92,106,110 Jepson Manual Treatment http plants.usda.gov java profile?symbol CHFE USDA Plants Profile http www.efloras.org florataxon.aspx?flora id 1&taxon id 233500351 Flora of North America http calphotos.berkeley.edu cgi img query?query src photos index&where taxon Cheilanthes feei Photo gallery Category Cheilanthes feei Category Fern species Category Ferns of California Category Ferns of the United States Category Flora of the California desert regions Category North American desert flora Category Flora of the Southwestern United States Category Flora of Missouri Category Flora of the West Coast of the United States Category Flora of the Western United States Category Flora of Northwestern Mexico ... more details
taxobox regnum Plantae unranked divisio Angiosperms unranked classis Eudicots unranked ordo Asterids ordo Asterales familia Asteraceae genus Antennaria species A. media binomial Antennaria media binomial authority Edward Lee Greene Greene synonyms Antennaria austromontana br Antennaria candida br Antennaria densa br Antennaria gormanii br Antennaria modesta br Antennaria mucronata Antennaria media is a species of flowering plant in the Asteraceae daisy family known by the common name Rocky Mountain pussytoes . It is native to western North America from Alaska and northwestern Canada to California to New Mexico , where it grows in cold regions such as the alpine climate of high mountain This is a perennial herb forming a matted patch of stolon s and woolly basal leaves with inflorescence s no more than about 13 centimeters tall. The inflorescences contain several Head botany flower heads . The species is plant sexuality dioecious , with male and female plants producing flower heads of slightly different morphologies. The fruit is an achene up to about 6 millimeters long, most of which is the long, soft Pappus flower structure pappus . Subspecies There are several subspecies one subspecies is Ploidy diploid and reproduces sexual reproduction sexually and the others are polyploidy polyploid and display apomixis . ref Chmielewski, J. G. 1997 . A taxonomic revision of the Antennaria media Asteraceae Inuleae polyploid species complex in western North America. Brittonia 49 3 309 27. ref References reflist External links http ucjeps.berkeley.edu cgi bin get JM treatment.pl?609,671,680 Jepson Manual Treatment http plants.usda.gov java profile?symbol ANME2 USDA Plants Profile http calphotos.berkeley.edu cgi img query?query src photos index&where taxon Antennaria media Photo gallery Category Antennaria media Category Alpine flora Category Flora of Western Canada Category Flora of the Western United States Category Flora of California Category Flora of the Sierra Nevada region ... more details
taxobox image Poacusickii.jpg regnum Plantae unranked divisio Angiosperms unranked classis Monocots unranked ordo Commelinids ordo Poales familia Poaceae genus Poa species P. cusickii binomial Poa cusickii binomial authority George Vasey botanist Vasey Poa cusickii is a species of Poaceae grass known by the common name Cusick s bluegrass . It is native to western North America from Yukon to Colorado to eastern California , where it grows in many types of habitat, including high mountain meadows and slopes, sagebrush scrub, and forests. It is a perennial bunchgrass growing dense, sometimes large, clumps up to about 60 centimeters in maximum height. The narrow leaves are firm and sometimes rolled along the edges. The longest leaves are located around the middle of the stem. The inflorescence is a dense, narrow series of overlapping branches bearing up to 100 spikelets in total. The grass is Plant sexuality dioecious , with male and female individuals producing different types of flowers in their inflorescences. The plant often reproduces vegetative reproduction vegetatively via tiller botany tillers , or via apomixis with unfertilized seeds, and some populations are made up only of female individuals. One subspecies, ssp. purpurascens , is all female. ref http www.fs.fed.us database feis plants graminoid poacus all.html US Forest Service Fire Ecology ref References reflist External links http ucjeps.berkeley.edu cgi bin get JM treatment.pl?8738,9207,9215 Jepson Manual Treatment http plants.usda.gov java profile?symbol POCU3 USDA Plants Profile http herbarium.usu.edu webmanual info2.asp?name Poa cusickii&type treatment Grass Manual Treatment Category Poa cusickii Category Bunchgrasses of North America Category Flora of the Sierra Nevada region U.S. Category Native grasses of California Category Grasses of the United States Category Grasses of Canada Pooideae stub ... more details
Taxobox image Cupressus dupreziana1.jpg status CR status system iucn2.3 regnum Plant ae divisio Pinophyta classis Pinophyta Pinopsida ordo Pinales familia Cupressaceae genus Cupressus species C. dupreziana binomial Cupressus dupreziana binomial authority A.Camus Cupressus dupreziana , the Saharan Cypress , is a very rare Pinophyta coniferous tree native to the Tassili n Ajjer mountains in the central Sahara Desert , southeast Algeria , where it forms a unique population of trees hundreds of kilometres from any other trees. There are only 233 specimens of this endangered species critically endangered species, the largest about 22 m tall. The majority are very old, estimated to be over 2000 years old, with very little regeneration due to the increasing desertification of the Sahara. Rainfall totals in the area are estimated to be about 30 mm annually. The largest one is named Tin Balalan is believed to be the oldest tarout tress with a circumference of 12 meters or 36 feet. This species is distinct from the allied Cupressus sempervirens Mediterranean Cypress in its much bluer foliage with a white resin spot on each leaf , the smaller shoots often being flattened in a single plane. It also has smaller conifer cone cones , only 1.5 2.5 cm long. Cupressus atlantica Moroccan Cypress is more similar, and is treated as a variety of the Saharan Cypress C. dupreziana var. atlantica by some authors. Probably as a result of its isolation and low population, the Saharan Cypress has Evolution evolved a unique reproductive system of apomixis male apomixis whereby the seed s develop entirely from the genetic content of the pollen . There is no genetic input from the female parent , which only provides nutritional sustenance Pichot et al. , 2000 . The Moroccan Cypress does not share this characteristic. The Saharan Cypress is occasionally cultivated in southern and western Europe , in part for ex situ genetic conservation, but also as an ornamental plant ornamental tree . ... more details
not involve a male gamete. Examples are parthenogenesis and apomixis . Parthenogenesis Main ... reptiles, amphibians, fish, very rarely birds . In plants, apomixis may or may not involve parthenogenesis. Apomixis and nucellar embryony Main Apomixis Main Nucellar embryony Apomixis in plants is the formation ..., but is very rare in other seed plants. In flowering plants, the term apomixis is now most often ... . Apomixis mainly occurs in two forms In gametophytic apomixis, the embryo arises from an unfertilized ... occurs in some citrus seeds. Male apomixis can occur in rare cases, such as the Saharan Cypress Cupressus ... apomixis is also used for asexual reproduction in some animals, notably water fleas, Daphnia . Alternation ... more details
Press location Chicago isbn 978 0 226 26554 4 pages 359 ref Seeds generated by apomixis are a means ... offspring. ref http www.lifescientist.com.au article 29781 why apomixis genetic gold ref Other forms of apomixis occur in plants also, including the generation of a plantlet in replacement ... more details
wiktionary clone tocright Clone may refer to Biological Cloning Clone In biology and agriculture, any organism whose genetic information is identical to that of a parent organism from which it was created natural reproductive processes producing clones include parthenogenesis and apomixis Clone cell biology In cell biology, a group of identical cells naturally derived from a common parent cell of significance in vertebrate physiology and concepts related to immunology and cancer biology Clone B cell biology In immunology, a process of immunological B cell maturation Clone genetics In genetics, an exact replica of all or part of a macromolecule e.g. DNA Computing Clone computing , a computer made by a third party, such as PC clones or Macintosh clones Clone database , a complete and modified copy of a database environment that s often used for development or testing purposes clone Linux system call , in C, relating to multithreading clone Java method , a method in the Java programming language for object duplication Entertainment Music Clone Threshold album , a 1998 album by British progressive metal band Threshold Clone Leo Kottke and Mike Gordon album Clone Leo Kottke and Mike Gordon album , the first studio album from Leo Kottke and Mike Gordon. It was released on October 8, 2002, and features the duo performing acoustic originals and cover songs on a variety of instruments Other Video game clone , a game or game franchise heavily inspired by another Clone TV series Clone TV series , a 2008 BBC comedy series O Clone , a Brazilian soap opera Clone Wars disambiguation Clone Wars Star Wars , a TV show and movie based around the Star Wars universe Clone trooper , a fictional soldier in the Star Wars universe The Clone Saga , a controversial story line from Marvel Comics Spider Man comic books Mathematics Clone algebra , a collection of functions with certain properties Other uses Clone voting , in voting systems analysis, a candidate identical to one already present i ... more details
Congener from Latin congener of the same race or kind, from com together gener , stem of genus kind has several different meanings depending on the field in which it is used. Colloquially, it is used to mean a person or thing like another, in character or action. Biology This section is linked from Apomixis In biology , congeners are organisms within the same genus . ref http www.merriam webster.com dictionary congener Congener , Merriam Webster.com. Accessed 2009 03 25 ref A related term referring to members of the same species is conspecific . Chemistry Image Polychlorinated biphenyl structure.svg thumb Example of a congener the number and locations of Cl groups can vary In chemistry , congeners are related chemicals, e.g., elements in the same group of the periodic table , or derivatives thereof. There are 209 congeners of polychlorinated biphenyls PCB as well as 209 congeners of polybrominated diphenyl ethers PBDE . Congeners of oleic acid s can modify cell membrane behavior protecting against tumors or having effects on blood pressure. Congeners refer to the other elements in a group in the periodic table . For example, the congeners of the Group 11 element copper are silver and gold . Similarly, sodium chloride and potassium chloride may be considered congeners. Genetics In genetics , congenic organisms are organisms with very similar genomes, except for a small fraction. For example, recombinant congenic mice strains are produced in laboratories as a tool to study genetic disease . In alcoholic beverages In the Distilled beverage alcoholic beverage s industry, congeners, also known as Fusel alcohol fusel oils , are substances produced during Ethanol fermentation fermentation . These substances include small amounts of chemicals such as acetone , acetaldehyde , and other fusel alcohol higher alcohols , esters , and aldehyde aldehydes e.g. propanol , glycols , ethyl acetate . Congeners are responsible for most of the taste and aroma of distilled alcoholic bever ... more details
Taxobox image Boechera drummondii.jpg image caption Boechera stricta regnum Plantae unranked divisio Angiosperms unranked classis Eudicots unranked ordo Rosids ordo Brassicales familia Brassicaceae genus Boechera genus authority Askell L ve A.L ve & Doris Benta Maria L ve D.L ve subdivision ranks Species subdivision See text. Boechera rockcress is a genus of the family Brassicaceae . It was named after the Denmark Danish botanist Tyge W. B cher 1909 1983 , who was known for his research in alpine plants, including the mustards Draba and Boechera holboellii . According to recent molecular based studies Boechera is closely related to the genus Arabidopsis which also includes the widely known model plant Arabidopsis thaliana . Until recently, members of this genus were included in the genus Arabis , but have been separated from that genus based on recent genetics genetic and cytological data. ref Al Shehbaz, I.A., 2003. Transfer of most North American species of Arabis to Boechera Brassicaceae . Novon 13 4 381 391. ref Unlike the genus Arabis x 8 Boechera has a base chromosome number of x 7. Many taxa are triploid. Boechera is a primarily North American genus, most diverse in the western United States but its distribution range also includes Greenland and the Russian Far East. The genus is poorly known, and species within are difficult to separate morphologically though some clearly distinct species are known. Most members of the genus are perennial plant s with pubescent leaves with stellate trichomes , narrow curving fruits, and small white to purple flower s in elongated raceme s. Relationships within the genus are unclear, and some eastern North American species, including Boechera laevigata , may belong to a clade distinct from the rest of the genus. A very interesting feature of many species of the genus is asexual reproduction , a process known as apomixis . Microsatellite genetics Microsatellite data has revealed that some of the apomictic lineages are Hybrid b ... more details
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