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North American Dryopteris Hybrid Complex
Hybridization and polyploidy are common phenomena in ferns, and the genus ''Dryopteris'' is known to be one of the most freely-hybridizing fern genera. North American botanists recognized early that there were close relationships between many of the species of ''Dryopteris'' on the continent, and that these relationships reflected hybrid ancestry. The complex includes six sexual diploid parents (one of which, "''D. semicristata"'', is hypothesized to be extinct), six sexual allopolyploids, and numerous sterile hybrids at various ploidal levels. Diploid species *''Dryopteris intermedia'' *'' Dryopteris expansa'' *''Dryopteris goldieana'' *''Dryopteris ludoviciana'' *''Dryopteris marginalis'' *''Dryopteris "semicristata"'' Allopolyploid species *''Dryopteris carthusiana'' (''D. intermedia'' × ''"D. semicristata"''; allotetraploid) *''Dryopteris campyloptera'' (''D. intermedia'' × ''D. expansa''; allotetraploid) *''Dryopteris celsa'' (''D. goldieana'' × ''D. ludoviciana''; allot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North American Dryopteris Reticulogram
North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating Direction (geometry), direction or geography. Etymology The word ''north'' is etymology, related to the Old High German ''nord'', both descending from the Proto-Indo-European language, Proto-Indo-European unit *''ner-'', meaning "left; below" as north is to left when facing the rising sun. Similarly, the other cardinal directions are also related to the sun's position. The Latin word ''borealis'' comes from the Ancient Greek, Greek ''Anemoi#Boreas, boreas'' "north wind, north", which, according to Ovid, was personified as the wind-god Anemoi#Boreas, Boreas, the father of Calais and Zetes. ''Septentrionalis'' is from ''septentriones'', "the seven plow oxen", a name of ''Ursa Major''. The Greek ἀρκτικός (''arktikós'') is named for the same constellation, and is the source of the English ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Marginalis
''Dryopteris marginalis'', vernacularly known as the marginal shield fern or marginal wood fern, is a perennial species of fern found in damp shady areas throughout eastern North America, from Texas to Minnesota and Newfoundland. It favors moderately acid to circumneutral soils in cooler areas but is fairly drought-resistant once established. In the warmer parts of its range, it is most likely to be found on north-facing non-calcareous rock faces. It is common in many altitudes throughout its range, from high ledges to rocky slopes and stream banks. Marginal wood fern's name derives from the fact that the sori are located on the margins, or edges of the leaflets. Description ''Dryopteris marginalis'' is an evergreen fern throughout its range, along with Christmas fern (''Polystichum acrostichoides'') it is one of the few evergreen ferns. Marginal wood fern grows from a clump with a prominent central rootstock, this rootstock may be exposed and give this fern the appearance of be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraploid
Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains one or more chromosomes and comes from each of two parents, resulting in pairs of homologous chromosomes between sets. However, some organisms are polyploid. Polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally diploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis, the sporophyte generation is diploid and produces spores by meio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triploid
Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei ( eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains one or more chromosomes and comes from each of two parents, resulting in pairs of homologous chromosomes between sets. However, some organisms are polyploid. Polyploidy is especially common in plants. Most eukaryotes have diploid somatic cells, but produce haploid gametes (eggs and sperm) by meiosis. A monoploid has only one set of chromosomes, and the term is usually only applied to cells or organisms that are normally diploid. Males of bees and other Hymenoptera, for example, are monoploid. Unlike animals, plants and multicellular algae have life cycles with two alternating multicellular generations. The gametophyte generation is haploid, and produces gametes by mitosis, the sporophyte generation is diploid and produces spores by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Filix-mas
''Dryopteris filix-mas'', the male fern, is a common fern of the temperate Northern Hemisphere, native to much of Europe, Asia, and North America. It favours damp shaded areas in the understory of woodlands, but also shady places on hedge-banks, rocks, and screes. Near the northern limit of its distribution it prefers sunny, well-drained sites. It is much less abundant in North America than in Europe. The plant is sometimes referred to in ancient literature as worm fern, reflecting its former use against tapeworm. Its specific epithet ''filix-mas'' means "male fern" (''filix'' "fern", ''mas'' "male"), as the plant was thought to be the male version of the common lady fern ''Athyrium filix-femina''. being robust in appearance and vigorous in growth. Description The semi-evergreen leaves have an upright habit and reach a maximum length of , with a single crown on each rootstock. The bipinnate leaves consist of 20–35 pinnae on each side of the rachis. The leaves taper at both end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Cristata
''Dryopteris cristata'' is a species of fern native to wetlands throughout the Northern Hemisphere. It is known as crested wood fern or crested buckler-fern. This plant is a tetraploid species of hybrid origin, one parent being ''Dryopteris ludoviciana'' and the other being the unknown, apparently extinct species, dubbed ''Dryopteris semicristata'', which is also one of the presumed parents of ''Dryopteris carthusiana''. ''D. cristata'' in turn is one of the parents of ''Dryopteris clintoniana'', another fern of hybrid origin. The crested wood fern is a wetlands plant, needing year-round moisture. The fronds often grow quite tall, up to a meter or more in height, but are extremely narrow under most conditions. Anti-microbial properties It is known that this plant has been used as an anti-microbial agent; for example, root extracts from ''D. cristata'' (as well as the kindred species ''Dryopteris arguta, D. arguta'') has been shown efficacious in expelling intestinal parasites fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Clintoniana
''Dryopteris clintoniana'', commonly known as Clinton's wood fern, is a fern of hybrid origin native to the northern hemisphere. It is a fertile hexaploid, arising as a species by doubling of its chromosome number from a hybrid between ''Dryopteris cristata'', a tetraploid, and ''Dryopteris goldieana ''Dryopteris goldieana'', commonly called Goldie's wood fern, or giant wood fern is a fern native to the eastern United States and adjacent areas of Canada, from New Brunswick to Ontario and Georgia. It is the largest native North American speci ...'', a diploid. It is more northern in its range than either parent species. This fern will be found in wet areas, similar to the habitat of ''D. cristata''. References * U.S. Department of Agriculture. 2009 Line notes Dryopteris, clintoniana Plants described in 1867 Flora of North America Flora of Asia Flora of Europe {{Dryopteridaceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Celsa
''Dryopteris celsa'', the log fern, is a perennial fern in the family Dryopteridaceae. It naturally occurs on rotting logs and the rich soil of swamps and wet woodlands. Its native range includes the southeastern United States. References Dryopteris, celsa Ferns of the United States {{Dryopteridaceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Campyloptera
''Dryopteris campyloptera'', also known as the mountain wood fern, is a large American fern of higher elevations and latitudes. It was formerly known as ''Dryopteris spinulosa'' var. ''americana''. This species also has been mistakenly referred to as ''D. austriaca'' and ''D. dilatata''. A distinctive feature of this fern is that the bottom innermost pinnule on the basal pinnae spans approximately the first two top innermost pinnules on the same pinnae. This fern is a tetraploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains ... species of hybrid origin, the parents being ''Dryopteris intermedia'' and ''Dryopteris expansa''. Phenotypologically, the fern greatly resembles the second parent. In West Virginia, this species may only be found above 3800 feet elevation, but is a part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Carthusiana
''Dryopteris carthusiana'' is a species of fern native to damp forests throughout the Holarctic Kingdom. It is known as the narrow buckler-fern in the United Kingdom, and as the spinulose woodfern in North America. It is a tetraploid of hybrid origin, one parent being ''Dryopteris intermedia'', known in North America as the intermediate wood fern, and an unknown, apparently extinct species dubbed ''Dryopteris semicristata'', which is also the presumed parent of the hybrid-origin ''Dryopteris cristata''. This fern is often confused with several other wood fern species, including ''D. intermedia'', '' D. campyloptera'', and '' D. expansa''. It especially extensively shares the range of ''D. intermedia'', but the two may be distinguished by the innermost pinnule on the bottom side of the bottom pinna: this pinnule is longer than the adjacent pinnules in ''D. carthusiana'', but shorter or even in ''D. intermedia''. ''D. carthusiana'' is a sub-evergreen species, its fronds surviving m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryopteris Ludoviciana
''Dryopteris ludoviciana'', the southern woodfern, is fern native to southern United States from Florida west to Texas and as far north as Kentucky and North Carolina. It is an evergreen in mild climates. Its growth habit is tall and upright with shiny and leathery dark green fronds. It will tolerate dry conditions but will perform best in moist areas. The growth rate is slow to moderate and reaches a mature height at 30–48 inches. ''D. ludoviciana'' is hardy in USDA plant hardiness zones A hardiness zone is a geographic area defined as having a certain average annual minimum temperature, a factor relevant to the survival of many plants. In some systems other statistics are included in the calculations. The original and most wide ... 5–10. References ludoviciana Ferns of the United States Endemic flora of the United States Flora of the Southeastern United States Flora of Florida Flora of Texas Flora of the Appalachian Mountains Least concern flora of the Unite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybridization (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in blending inheritance), but can show Heterosis, hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductive isolation, reproductively isolated by strong barriers to hybridisation, which include genetic and morphological differences, differing times of fertility, mating behaviors and cues, and physiological rejection of sperm cells or the developing embryo. Some act before fertilization and others after it. Similar barriers exist in plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
