Image Physcomitrella Protonema.jpg thumb Protonema cells of the moss Physcomitrella patens A protonema plural protonemata is a thread like chain of cells that forms the earliest stage the haploid phase of a bryophyte life cycle. When a moss first grows from the spore , it grows as a protonema which develops into a leafy gametophore . Marchantiophyta Liverworts do not have a protonemal stage, the spores Germination germinate directly into a new Gametophyte generation. Moss spores Germination germinate to form an alga like filamentous structure called the protonema. It represents the juvenile gametophyte . While the protonema is growing by apical cell division, at some stage, under the influence of the phytohormone cytokinin , bud s are induced which grow by three faced apical cells. These give rise to gametophore s, stems and leaf like structures bryophytes do not have true leaves megaphyll . These gametophores are the adult form of the gametophyte ref Ralf Reski 1998 Developmental biology Development , genetics and molecular biology of moss es. Botanica Acta 111, 1 15. ref . Protonema are characteristic of all mosses and some liverworts but are absent from hornwort s. The protonema is also the photosynthetic part of a germinating fern spore. References reflist botany stub Category Bryophytes cs Prvokl ek de Protonema es Protonema fr Protonema pl Spl tek pt Protonema ru sv Protonema uk zh ... more details
Image Physcomitrella patens Gametophor.JPG thumb Single gametophore of Physcomitrella patens The word gametophore , also known as gametangiophore, is composed of gametangium and phore Greek , to be carried . ref http www.mobot.org MOBOT tropicos most Glossary glosefr.html Bryological Glossary ref In moss and fern Archegoniata the gametophore is the bearer of the sex organs gametangia , the female archegonia and the male antheridia . ref name Ralf Reski 1998 Ralf Reski 1998 Development , genetics and molecular biology of mosses. Botanica Acta 111, 1 15. ref If the archegonia as well as the antheridia are arranged at the same plant, they are called monoecious . If there are female and male plants they are called dioecious . In Bryopsida the leafy moss plant q. v. Thallus is called gametophore. It is the adult form of the haploid gametophyte and develops from the juvenile form, the protonema , under the influence of phytohormones mainly cytokinins . ref name Ralf Reski 1998 Whereas the wikt filamentous filamentous protonema grows by apical dominance apical cell division, the gametophore grows by division of three faced apical cells. References references Category Plant morphology botany stub de gametophor pl Gametofor ... more details
A sporeling is a young plant or fungus produced by a germinated spore , similar to a seedling derived from a germinated seed . They occur in alga e, fungus fungi , lichen s, bryophyte s and Pteridophyte seedless vascular plant s. Sporeling development Most spores germinate by first producing a germ rhizoid or holdfast followed by a germ tube emerging from the opposite end. The germ tube develops into the hypha , protonema or thallus tissue thallus of the gametophyte . In seedless vascular plants such as fern s and lycopodiophyta , the term sporeling refers to the young sporophyte growing on the gametophyte. These sporelings develop via an embryo stage from a fertilized egg inside an archegonium and depend on the gametophyte for their early stages of growth before becoming independent sporophytes. Young fern sporelings can often be found with the prothallus gametophyte still attached at the base of their frond s. External links British Pteridological Society http www.nhm.ac.uk hosted sites bps wof wof.htm An introduction to ferns contains a picture of a sporeling fern attached to the prothallus botany stub Category Plant morphology Category Plant reproduction Category Fungal morphology and anatomy ... more details
File Gametophyte2.png thumb Several gametophytes growing in a terrarium . Image Physcomitrella Protonema.jpg thumb Protonema of the moss Physcomitrella patens A gametophyte is the haploid , multicellular phase of plant s and algae that undergo alternation of generations , with each of its cells containing only a single set of chromosomes . The gametophyte produces male or female gamete s or both , by a process of cell division called mitosis . Sexual reproduction of plants The fusion of male and female gametes produces a diploid zygote , which develops by repeated mitotic cell divisions into a multicellular sporophyte . Because the sporophyte is the product of the fusion of two haploid gametes , its cells are diploid , containing two sets of chromosomes. The mature sporophyte produces spore s by a process called meiosis , sometimes referred to as reduction division because the chromosome pairs are separated once again to form single sets. The spores are therefore once again haploid and develop into a haploid gametophyte. In moss es, Marchantiophyta liverworts and Anthocerotophyta hornworts bryophytes , the gametophyte is the commonly known phase of the plant. An early developmental stage in the gametophyte of mosses immediately following germination of the meiospore is called the protonema . The adult gametophyte of mosses is called the gametophore as it carries the gamete producing sex organs. ref Ralf Reski 1998 Development, genetics and molecular biology of mosses. In Botanica Acta 111, pp 1 15. ref In most other embryophyte land plants , the gametophyte is very small. In fern s the gametophyte is a free living organism called the prothallus , in contrast to angiosperms. ref C.Michael Hogan. 2010. http www.eoearth.org article Fern Fern . Encyclopedia of Earth. National council for Science and the Environment . Washington, DC ref In gymnosperm s and angiosperm s, the gametophyte are reduced to only a few cells in angiosperms the female gametophyte sometimes called ... more details
italic title There is not an upper level in the taxonomy tree of articles linked to this article Taxobox image Wortel violet wortelrot Helicobasidium brebissonii on Daucus carota .jpg image caption Helicobasidium purpureum on Daucus carota name Helicobasidium purpureum regnum Fungi phylum Basidiomycota classis Pucciniomycetes subclassis Incertae sedis ordo Helicobasidiales familia Helicobasidiaceae genus Helicobasidium species H. purpureum binomial Helicobasidium purpureum binomial authority Tul. Pat. 1885 synonyms Corticium sanguineum var. lilacinum small small br Helicobasidium brebissonii small Desm. Donk, 1958 small br Hypochnus purpureus small small br Protonema brebissonii small small br Rhizoctonia asparagi small small br Rhizoctonia crocorum small small br Rhizoctonia medicaginis small small br Rhizoctonia rubiae small small br Rhizoctonia violacea small small br Rhizoctonia violacea f. dauci small small br Sclerotium crocorum small small br Thanatophytum crocorum small small br Tuber parasiticum small small Helicobasidium purpureum is a plant pathogen. It contains 3 variations. Variations Helicobasidium purpureum var. barlae small Bres. 1909 small Helicobasidium purpureum var. orientale small Pat. 1920 small Helicobasidium purpureum var. purpureum small Tul. Pat. 1885 small External links http www.speciesfungorum.org Names Names.asp Index Fungorum http nt.ars grin.gov fungaldatabases USDA ARS Fungal Database References references DEFAULTSORT Helicobasidium purpureum Category Plant pathogens and diseases Category Teliomycotina Teliomycotina stub plant disease stub fr Helicobasidium brebissonii nl Violet wortelrot ... more details
for the 1992 Japanese film Luminous Moss film italic title Taxobox name Schistostega image Hikarigoke.JPG image width 240px image caption Luminous moss photographed in Japan. name Bryidae regnum Plant ae divisio Moss Bryophyta classis Bryopsida subclassis Dicranidae ordo Dicranales familia Schistostegaceae familia authority Schimp. genus Schistostega genus authority D. Mohr species S. pennata binomial Schistostega pennata binomial authority Hedw. F.Weber & D.Mohr Schistostega pennata , also called goblin s gold or luminous moss or luminescent moss ref USDA Forest Service, http www.fs.fed.us gpnf 04projects pinchotprojects documents feis ch3.pdf Gotchen Risk Reduction and Restoration Project ref , is a moss known for its glowing appearance in dark places. It is the only member of the family Schistosteagaceae . The moss s greenish gold glowing appearance is due to the clear, spherical cells in the protonema that can collect even the faintest light like lenses, and the chloroplasts nearby in turn give off the greenish glow from the reflected light. ref name Washington http www.stage.dnr.wa.gov nhp refdesk fguide pdf schpen.pdf Schistostega pennata . Reference Desk of the Washington Natural Heritage Program. br http www.botanic.jp plants ha higoke.htm Japanese Botanic Garden ref It is easily outcompeted by other mosses and plant species in open lighter areas, but its ability to reflect light allows it to grow in shady places that other plants cannot survive. It prefers damp mineral soils with a source of dim light, such as reflection from a pool, overturned tree roots, and entrances to animal burrows. S. pennata is found in China, Japan, Siberia, Europe, and North America. ref name china http www.efloras.org florataxon.aspx?flora id 4&taxon id 240002105 Schistostega pennata . Moss Flora of China . ref References references External links Wikispecies Schistostega pennata http www.nps.gov archive olym crypto M SCPE lum.htm Photo from Olympic National Park click to enlarge ... more details
Italictitle Taxobox name Oedipodium griffithianum image image width 240px image caption regnum Plant ae divisio Moss Bryophyta classis Oedipodiopsida classis authority Goffinet & W.R.Buck ref name Goffinet & Buck 2004 cite journal last Goffinet first Bernard coauthors William R. Buck year 2004 title Systematics of the Bryophyta Mosses From molecules to a revised classification series Molecular Systematics of Bryophytes journal Monographs in Systematic Botany volume 98 pages 205 239 publisher Missouri Botanical Garden Press ref ordo Oedipodiales ordo authority Goffinet & W.R.Buck ref name Goffinet & Buck 2004 familia Oedipodiaceae familia authority Schimp. ref name Schimper cite book last Schimper first Wilhelm Philippe year 1876 title Synopsis Muscorum Europaea edition 2nd volume XCVIII page 354 location Stuttgart ref genus Oedipodium genus authority Schw gr. ref name Schw grichen cite book last Schw grichen first Christian Friedrich year 1823 title Species Muscorum frondosorum volume Supplementum 2 1,1 page 15 ref species O. griffithianum binomial Oedipodium griffithianum binomial authority Dickson Schw gr. ref name Schw grichen Oedipodium is the only genus of moss in the family Oedipodiaceae it contains the single species Oedipodium griffithianum . This species is distributed in cooler climates of Eurasia , North America North and South America , and islands in the northern Atlantic Ocean Atlantic . ref name Crum 2002 cite book last Crum first Howard A. year 2002 title Flora of North America volume 27 chapter Oedipodiaceae pages 116 117 chapterurl http www.efloras.org florataxon.aspx?flora id 1&taxon id 10623 isbn 978 0 19 531823 4 ref The relationship of Oedipodium to other mosses has been much debated. Previously, the taxon has been included with the Funariales or the Splachnales . However, characteristics of the protonema ta and asexual propagation, along with molecular evidence, point to a closer relationship with the Tetraphidaceae . ref name Crum 2002 Moss p ... more details
Taxobox name Bryopsidales image codiumfragile.jpg image width 240px image caption Dead man s fingers Codium fragile domain Eukaryota regnum Plant ae divisio Chlorophyta classis Bryopsidophyceae ordo Bryopsidales ordo authority J.H. Schaffner subdivision ranks Family biology Families ref name Algaebase cite web url http www.algaebase.org browse taxonomy ?id 4585 publisher AlgaeBase version 4.2 World wide electronic publication, National University of Ireland, Galway accessdate 2007 09 23 title Order Bryopsidales taxonomy browser author Guiry, M.D. & Guiry, G.M. year 2007 ref subdivision Bryopsidaceae Caulerpaceae Chaetosiphonaceae Codiaceae Derbesiaceae Dichtomosiphonaceae Halimedaceae Ostreobiaceae Pseudocodiaceae Udoteaceae synonyms Caulerpales Bryopsidales is an order biology order of green algae , in the Class biology class Bryopsidophyceae . ref name Algaebase Characteristics The thallus is filamentous and much branched and may be packed into a mass. It is Coenocyte coenocytic , having multi nucleate cells consisting of cytoplasm contained within a cylindrical cell wall . There are no Septum septae and the many discoid chloroplasts, nuclei and other organelle s are free to move through the organism. The whole organism may consist of a single cell and in the genus Caulerpa this may be several metres across. In the genus Halimeda , whole seabed meadows may consist of an individual, single celled organism connected by filamentous threads running through the substrate. Reproduction Propagation is normally Asexual reproduction vegetative from small fragments which grow into new individuals. Under certain conditions sexual reproduction occurs in a process called holocarpy. Almost all of the cytoplasm in the thallus is converted into biflagellate gamete s, which are discharged into the sea through papillae. After fertilisation, the zygote becomes a protonema and this in turn develops into a new thallus. ref http www.angelfire.com ri skibizniz bryopsidales.html The Cell ... more details
Infobox scientist name Johann Hedwig image Johann Hedwig.jpg image size frameless caption Johann Hedwig, 1793 birth date 8 December 1730 birth place Romania death date 18 February 1799 death place residence citizenship nationality Germany German ethnicity field botany work institutions alma mater University of Leipzig doctoral advisor doctoral students known for bryology author abbrev bot Hedw. File Joannis Hedwig00.jpg thumb File Joannis Hedwig01.jpg thumb left center Plate 1 Species Muscorum Frondosorum Johann Hedwig 8 December 1730 18 February 1799 , also seen as Johannes Hedwig or Latinised as Joannis Hedwig , was a Germany German botanist notable for his studies of moss es for which he is sometimes called the father of bryology , in particular the observation of sexual reproduction in the cryptogams . He was born in Romania , and studied medicine at the University of Leipzig , receiving an M.D. in 1759. He then practiced as a physician for the next twenty years, during which time he pursued botany as a hobby, collecting in the morning before work and then studying his accumulation in the evening. He also acquired a microscope and a small library. Over time his publications attracted attention, and he eventually achieved both a professorship at Leipzig first in medicine in 1786, then in botany in 1789 , and direction of the Leipzig Botanical Garden . Skilled at both microscopy and biological illustration, he was able to identify moss antheridia and archegonia . He directly observed the germination of spores and formation of the protonema . He was less successful with other sporophyte s, being unable to determine the life cycles of fern s or fungi , but he did make useful observations on the algae Chara alga Chara and Spirogyra and he made it clear that he was not the first to get new plants from sowing the spores of mosses, C. Meese had done it before him. ref name Morton 81 Morton, A.G. 1981. History of Botanical Science. Academic Press Inc. London Ltd. ISBN 0 ... more details
to divide new cells, which produces a thalloid protonema . By contrast, species of the family ... before the spore germinates. ref name Chopra 1988 In either case, the protonema is a transitory stage ... hornwort Phaeoceros . Click on the image to enlarge. From the protonema grows the adult gametophyte ... more details
. A spore develops into a filamentous structure called protonema , composed of two types of cells chloronema with large and numerous chloroplasts and caulonema with very fast growth. Protonema filaments ... more details
. The spores require a moist substrate to Germination germinate . A germinated spore develops into a protonema a branched, threadlike structure . Rhizoids grow down from the protonema and penetrate the substrate. Stems arise from buds that develop on the protonema surface. As stems grow, they develop their own rhizoids and become independent of the protonema. Mature male and female stems develop ... more details
a protonema pl. protonemata , which is either a mass of thread like filaments or thalloid flat and thallus ... of a moss, but from the protonema grows the gametophore gamete bearer that is structurally ... this character, the unique branching, thallose flat and expanded protonema, and explosively rupturing ... by the biseriate two rows of cells rhizoids, multiseriate many rows of cells protonema, and sporangium ... more details
of a haploid spore to produce a protonema , which is either a mass of thread like filaments or else ... 0. ref The protonema is a transitory stage in the life of a liverwort, from which will grow the mature ... more details
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