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Androgenetic Alopecia
In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cuttings or leaves, has never been considered to be apomixis, but replacement of the seed by a plantlet or replacement of the flower by bulbils were categorized as types of apomixis. Apomictically produced offspring are genetically identical to the parent plant. Some authors included all forms of asexual reproduction within apomixis, but that generalization of the term has since died out. In flowering plants, the term "apomixis" is commonly used in a restricted sense to mean agamospermy, i.e., clonal reproduction through seeds. Although agamospermy could theoretically occur in gymnosperms, it appears to be absent in that group. Apogamy is a related term that has had various meanings over time. In plants with independent gametophytes (notab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poa Bulbosa, Vegetative Apomixis
''Poa'' is a genus of about 570 species of grasses, native to the temperate regions of both hemispheres. Common names include meadow-grass (mainly in Europe and Asia), bluegrass (mainly in North America), tussock (some New Zealand species), and speargrass. ''Poa'' () is Greek for "fodder". ''Poa'' are members of the subfamily Pooideae of the family Poaceae. Bluegrass, which has green leaves, derives its name from the seed heads, which are blue when the plant is allowed to grow to its natural height of two to three feet (0.6 to 0.9 meters). The genus ''Poa'' includes both annual and perennial species. Most are monoecious, but a few are dioecious (separate male and female plants). The leaves are narrow, folded or flat, sometimes bristled, and with the basal sheath flattened or sometimes thickened, with a blunt or hooded apex and membranaceous ligule. Cultivation and uses Many of the species are important pasture plants, used extensively by grazing livestock. Kentucky bluegrass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bramble
A bramble is any rough, tangled, prickly shrub, usually in the genus ''Rubus'', which grows blackberries, raspberries, or dewberries. "Bramble" is also used to describe other prickly shrubs, such as roses (''Rosa'' species). The fruits include blackberries, arctic brambleberries, or raspberries, depending on the species, and are used to make jellies, jams, and preserves. In British English, bramble usually refers to the common blackberry, ''Rubus fruticosus''. ''R. fruticosus'' grows abundantly in all parts of the British Isles, and harvesting the fruits in late summer and autumn is often considered a favourite pastime. An especially hardy plant, bramble bushes can also become a nuisance in gardens, sending down strong suckering roots amongst hedges and shrubs and being particularly resilient against pruning. Many consider ''R. fruticosus'' a weed due its tendency to grow in neglected areas and its sharp, tough thorns, which can be hazardous to children and pets. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawkweed
''Hieracium'' (), known by the common name hawkweed and classically as (from ancient Greek ιεράξ, 'hawk'), is a genus of flowering plant in the family Asteraceae, and closely related to dandelion ('' Taraxacum''), chicory (''Cichorium''), prickly lettuce ('' Lactuca'') and sow thistle (''Sonchus''), which are part of the tribe Cichorieae. Hawkweeds, with their 10,000+ recorded species and subspecies, do their part to make Asteraceae the second largest family of flowering plants. Some botanists group all these species or subspecies into approximately 800 accepted species, while others prefer to accept several thousand species. Since most hawkweeds reproduce exclusively asexually by means of seeds that are genetically identical to their mother plant (apomixis or agamospermy), clones or populations that consist of genetically identical plants are formed and some botanists (especially in UK, Scandinavia and Russia) prefer to accept these clones as good species (arguing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nardus Stricta
''Nardus'' is a genus of plants belonging to the grass family, containing the single species ''Nardus stricta'', known as matgrass. It is placed in its own tribe Nardeae within the subfamily Pooideae. The name derives from ancient Greek ' () from the earlier Akkadian ''lardu''. It is not to be confused with spikenard, '' Nardostachys jatamansi''. Distribution and ecology ''Nardus stricta'' is native to Eurasia (from Iceland and the Azores to Mongolia), North Africa (Algeria, Morocco), and northeastern North America (Greenland, eastern Canada, and the northeastern United States). ''Nardus stricta'' occurs on heath, moorland, hills, and mountains on nutrient poor acidic sandy to peaty soils and is strongly calcifuge, avoiding calcareous soils. It can occur from low elevations to over , becoming a community-dominant in late snow patches on mountains. ''Nardus stricta'' may also become a dominant species in habitats grazed by cattle or sheep because it is tough and unpalatable. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meadow Grass
''Poa'' is a genus of about 570 species of grasses, native to the temperate regions of both hemispheres. Common names include meadow-grass (mainly in Europe and Asia), bluegrass (mainly in North America), tussock (some New Zealand species), and speargrass. ''Poa'' () is Greek for " fodder". ''Poa'' are members of the subfamily Pooideae of the family Poaceae. Bluegrass, which has green leaves, derives its name from the seed heads, which are blue when the plant is allowed to grow to its natural height of two to three feet (0.6 to 0.9 meters). The genus ''Poa'' includes both annual and perennial species. Most are monoecious, but a few are dioecious (separate male and female plants). The leaves are narrow, folded or flat, sometimes bristled, and with the basal sheath flattened or sometimes thickened, with a blunt or hooded apex and membranaceous ligule. Cultivation and uses Many of the species are important pasture plants, used extensively by grazing livestock. Kentucky blu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubus
''Rubus'' is a large and diverse genus of flowering plants in the rose family, Rosaceae, subfamily Rosoideae, with over 1,350 species. Raspberries, blackberries, and dewberries are common, widely distributed members of the genus. Most of these plants have woody stems with prickles like roses; spines, bristles, and gland-tipped hairs are also common in the genus. The ''Rubus'' fruit, sometimes called a bramble fruit, is an aggregate of drupelets. The term "cane fruit" or "cane berry" applies to any ''Rubus'' species or hybrid which is commonly grown with supports such as wires or canes, including raspberries, blackberries, and hybrids such as loganberry, boysenberry, marionberry and tayberry. The stems of such plants are also referred to as canes. Description Most species in the genus are hermaphrodites, '' Rubus chamaemorus'' being an exception. ''Rubus'' species have a basic chromosome number of seven. Polyploidy from the diploid (14 chromosomes) to the tetradecapl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whitebeam
The whitebeams are members of the family Rosaceae, comprising subgenus ''Aria'' (or, according to some authorities, its own genus) of genus ''Sorbus'', and hybrids involving species of this subgenus and members of subgenera ''Sorbus'', ''Torminaria'' and ''Chamaemespilus''. They are deciduous trees with simple or lobed leaves, arranged alternately. They are related to the rowans (''Sorbus'' subgenus ''Sorbus''), and many of the endemic restricted-range apomictic microspecies of whitebeam in Europe are thought to derive from hybrids between ''S. aria'' and the European rowan ''S. aucuparia''; some are also thought to be hybrids with the wild service tree ''S. torminalis'', notably the service tree of Fontainebleau ''Sorbus latifolia'' in French woodlands. The best known species is the common whitebeam ''Sorbus aria'', a columnar tree which grows to tall by broad, with clusters of white flowers in spring followed by speckled red berries in autumn (fall). Appearance The surface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rowan
The rowans ( or ) or mountain-ashes are shrubs or trees in the genus ''Sorbus'' of the rose family, Rosaceae. They are native throughout the cool temperate regions of the Northern Hemisphere, with the highest species diversity in the Himalaya, southern Tibet and parts of western China, where numerous apomictic microspecies occur.Rushforth, K. (1999). ''Trees of Britain and Europe''. Collins . The name ''rowan'' was originally applied to the species ''Sorbus aucuparia'' and is also used for other species in ''Sorbus'' subgenus ''Sorbus''. Formerly, when a wider variety of fruits were commonly eaten in Europe and North America, ''Sorbus'' was a domestically used fruit throughout these regions. It is still used in some countries, but '' S. domestica'', for example, has largely vanished from Britain, where it was traditionally appreciated. Natural hybrids, often including ''S. aucuparia'' and the whitebeam, '' Sorbus aria'', give rise to many endemic variants in the UK. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sorbus
''Sorbus'' is a genus of over 100 species of trees and shrubs in the rose family, Rosaceae. Species of ''Sorbus'' (''s.l.'') are commonly known as whitebeam, rowan ( mountain-ash) and service tree. The exact number of species is disputed depending on the circumscription of the genus, and also due to the number of apomictic microspecies, which some treat as distinct species, but others group in a smaller number of variable species. Recent treatmentsRobertson, K. R., J. B. Phipps, J. R. Rohrer, and P. G. Smith. 1991. A Synopsis of Genera in Maloideae (Rosaceae). ''Systematic Botany'' 16: 376–394.McAllister, H. 2005. The Genus ''Sorbus'': Mountain Ash and Other Rowans. Richmond, Surrey, UK: Royal Botanic Gardens, Kew.Potter, D., T. Eriksson, R. C. Evans, S.-H. Oh, J. E. E. Smedmark, D.R. Morgan, M. S. Kerr, and C. S. Campbell. (2007). Phylogeny and classification of Rosaceae. ''Plant Systematics and Evolution''. 266(1–2): 5–43.Campbell C. S., R. C. Evans, D. R. Morgan, T. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amelanchier
''Amelanchier'' ( ), also known as shadbush, shadwood or shadblow, serviceberry or sarvisberry (or just sarvis), juneberry, saskatoon, sugarplum, wild-plum or chuckley pear,A Digital Flora of Newfoundland and Labrador Vascular Plants/ref> is a genus of about 20 species of deciduous-leaved shrubs and small trees in the rose family (Rosaceae). ''Amelanchier'' is native to temperate regions of the Northern Hemisphere, growing primarily in early successional habitats. It is most diverse taxonomically in North America, especially in the northeastern United States and adjacent southeastern Canada, and at least one species is native to every U.S. state except Hawaii and to every Canadian province and territory. Two species also occur in Asia, and one in Europe. The taxonomic classification of shadbushes has long perplexed botanists, horticulturalists, and others, as suggested by the range in number of species recognized in the genus, from 6 to 33, in two recent publications. A major so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crataegus
''Crataegus'' (), commonly called hawthorn, quickthorn, thornapple, Voss, E. G. 1985. ''Michigan Flora: A guide to the identification and occurrence of the native and naturalized seed-plants of the state. Part II: Dicots (Saururaceae–Cornaceae)''. Cranbrook Institute of Science and University of Michigan Herbarium, Ann Arbor, Michigan. May-tree,Graves, Robert. ''The White Goddess: A Historical Grammar of Poetic Myth'', 1948, amended and enlarged 1966, New York: Farrar, Straus and Giroux. whitethorn, Mayflower, or hawberry, is a genus of several hundred species of shrubs and trees in the family Rosaceae, native to temperate regions of the Northern Hemisphere in Europe, Asia, North Africa, and North America. The name "hawthorn" was originally applied to the species native to northern Europe, especially the common hawthorn ''C. monogyna'', and the unmodified name is often so used in Britain and Ireland. The name is now also applied to the entire genus and to the related Asia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rosaceae
Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. Among the most species-rich genera are '' Alchemilla'' (270), ''Sorbus'' (260), '' Crataegus'' (260), '' Cotoneaster'' (260), ''Rubus'' (250), and ''Prunus'' (200), which contains the plums, cherries, peaches, apricots, and almonds. However, all of these numbers should be seen as estimates—much taxonomic work remains. The family Rosaceae includes herbs, shrubs, and trees. Most species are deciduous, but some are evergreen. They have a worldwide range but are most diverse in the Northern Hemisphere. Many economically important products come from the Rosaceae, including various edible fruits, such as apples, pears, quinces, apricots, plums, cherries, peaches, raspberries, blackberries, loquats, strawberries, rose hips, hawthorns, and almonds. The family also includes popular ornamental trees and sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
