essay like date June 2010 Aerenchyma is an air channel in the root s of some plants, which allows exchange of gases between the shoot and the root. The channel of large air filled cavities provides a low resistance internal pathway for the exchange of gases such as oxygen and ethylene between the plant above the water and the submerged tissues . Aerenchyma form in roots subject to anoxia such as what occurs during flooding of plants and soil ref name Visser et al ., 1997 Visser et al ., 1997 ref . For example, Blom et al. 1994 investigated the adaptive responses of plants to flooding along the banks of the Rhine River, which included such morphological changes such as aerenchyma formation. Aerenchyma formation Image Aerenchyma2.JPG thumb Aerenchyma of Schoenoplectus tabernaemontani In maize, an aerenchyma is formed from highly selective cell death and dissolution in the root cortex during anoxia in the roots ref He et al. 1994 ref . When plant roots are submerged or the surrounding soil flooded, hypoxia develops, as soil microorganisms consume oxygen faster than diffusion occurs. Nitrification is inhibited as low oxygen occurs and toxic compounds are formed, as anaerobic bacteria use ... of Aerenchyma Aerenchymas are formed by cell differentiation and collapse lysigenous aerenchyma or by cell separation without collapse schizogenous aerenchyma . The differentiation or separation ... of aerenchyma The large air filled cavities provide a low resistance internal pathway for the exchange ... transported through the aerenchyma leaks through root pores into the surrounding soil. The resulting ... are available. Disadvantages of Aerenchyma Not all plants are able to develop aerenchymas. Aerenchymous ... a higher bulk density and a strongly lignified layer of cells surrounding the aerenchyma, which strengthens the root. This dense, lignified layer prevents radial leakage of oxygen from the aerenchyma ..., roots with aerenchyma may be less tolerant to water stress as the open structure of the cortex ... more details
italic title Taxobox name Longitarsus regnum Animal ia phylum Arthropod a classis Insect a ordo beetle Coleoptera familia Chrysomelidae subfamilia Galerucinae tribus Flea beetle Alticini genus Longitarsus genus authority Pierre Andr Latreille Latreille , 1829 Longitarsus is a genus of beetle s in the family Chrysomelidae . It is the most speciose genus of flea beetle s, comprising over 700 species, and has a cosmopolitan distribution . ref name ZK87 cite journal author K. D. Prathapan & C. A. Viraktamath year 2011 title A new species of Longitarsus Latreille, 1829 Coleoptera, Chrysomelidae, Galerucinae pupating inside stem aerenchyma of the hydrophyte host from the Oriental Region journal ZooKeys volume 87 pages 1 10 doi 10.3897 zookeys.87.1294 ref See also Longitarsus jacobaeae References reflist Category Chrysomelidae Chrysomelidae stub nl Longitarsus ru ... more details
taxobox regnum Plantae unranked divisio Angiosperms unranked classis Monocots unranked ordo Commelinids ordo Poales familia Cyperaceae genus Amphiscirpus species A. nevadensis binomial Amphiscirpus nevadensis binomial authority Sereno Watson S.Watson Oteng Yeb. synonyms Scirpus nevadensis Amphiscirpus is a monotypic genus of flowering plants in the Cyperaceae sedge family containing the single species Amphiscirpus nevadensis , which is known by the common name Nevada bulrush . This plant was formerly included in genus Scirpus . ref Goetghebeur, P. and D. A. Simpson. 1991 . Critical notes on Actinoscirpus , Bolboschoenus , Isolepis , Phylloscirpus and Amphiscirpus Cyperaceae . Kew Bulletin 46 1 169 78. ref It is native to western North America, including the western Canadian provinces and the northwestern United States, as well as southern South America. It grows in wet and seasonally wet habitat, often on Soil salinity saline and alkali soils alkaline soils . It is a perennial herb growing from a small, hard rhizome . The erect stems are stiff, ridged, and cylindrical, not three angled. It lacks aerenchyma , a trait which makes it different from many of its relatives. The stems are sheathed by tough long leaves. The inflorescence is a headlike cluster of a few cone shaped spikelets accompanied by a long, stiff bract which looks like an extension of the stem. References reflist External links http ucjeps.berkeley.edu cgi bin get JM treatment.pl?7928,8145,8159 Jepson Manual Treatment http plants.usda.gov java profile?symbol SCNE USDA Plants Profile http www.efloras.org florataxon.aspx?flora id 1&taxon id 220000614 Flora of North America http calphotos.berkeley.edu cgi img query?query src photos index&where taxon Scirpus nevadensis Photo gallery Category Cyperaceae Category Monotypic plant genera Cyperaceae stub ... more details
italic title taxobox name Carex aquatilis image Carexaquatilis cropped.jpg image width 100px regnum Plantae unranked divisio Angiosperms unranked classis Monocots unranked ordo Commelinids ordo Poales familia Cyperaceae genus Carex species C. aquatilis binomial Carex aquatilis binomial authority G ran Wahlenberg Wahlenb. Carex aquatilis is a species of Carex sedge known by the common names water sedge and leafy tussock sedge . It has a Circumboreal Region circumboreal distribution, occurring throughout the northern reaches of the Northern Hemisphere. It grows in many types of mountainous and Arctic habitat, including temperate coniferous forest , alpine tundra alpine meadows , tundra , and wetland s. There are several varieties of this species, and it is somewhat variable in appearance. It produces triangular stems reaching heights between 20 centimeters and 1.5 meters, and generally does not form clumps as some other sedges do. It grows from a dense rhizome network which produces a mat of fine roots thick enough to form sod , and includes aerenchyma to allow the plant to survive in low oxygen substrates like heavy mud. ref name fs http www.fs.fed.us database feis plants graminoid caraqu all.html US Forest Service Fire Ecology ref The inflorescence bears a number of spikes with one leaflike bract at the base which is longer than the inflorescence itself. The fruits are glossy achene s, and although the plant occasionally reproduces by seed, most of the time it vegetative reproduction reproduces vegetatively , spreading via its rhizome. ref name fs In fact, in any given year, most shoots produce no flowers. ref name fs This perennial plant lives up to 10 years or more, can form peat as its rhizome system decomposes, and is sometimes used to revegetation revegetate areas where peat has been harvested. ref name fs References reflist External links http ucjeps.berkeley.edu cgi bin get JM treatment.pl?7928,7931,7939 Jepson Manual Treatment http plants.usda.gov java profi ... more details
aerenchyma , and ebullition . Diffusion Diffusion through the profile refers to the movement of methane .... Aerenchyma Plant aerenchyma refers to the vessel like transport tubes within the tissues of certain ... this transport system ref name Couwenberg . The direct shunt created by the aerenchyma allows for methane ... more details
About the plant commonly called saltgrass the restaurant concept Saltgrass Steakhouse italic title taxobox name Distichlis spicata image Dist3 001 svp.jpg regnum Plantae unranked divisio Angiosperms unranked classis Monocots unranked ordo Commelinids ordo Poales familia Poaceae subfamilia Chloridoideae genus Distichlis genus authority Constantine Samuel Rafinesque Raf. species D. spicata binomial Distichlis spicata binomial authority Carolus Linnaeus L. Edward Lee Greene Greene synonyms Distichlis stricta br Uniola stricta Distichlis spicata is a species of Poaceae grass known by several common names, including seashore saltgrass , inland saltgrass , and desert saltgrass . This grass is native to the Americas , where it is widespread. It can be found on other continents as well, where it is Introduced species naturalized . Distribution and habitat Distichlis spicata thrives along coastlines and on salt flats and disturbed soils, as well as forest, woodland, montane , and desert scrub habitats. It can form dense monotypic stands, and it often grows in Clonal colony clonal colonies . Non clonal populations tend to be skewed toward a majority of one sex or the other. The grass forms sod with its hearty root system. Its rhizomes have sharp points which allow it to penetrate hard soils and Aerenchyma aerenchymous tissues, which allow it to grow underwater and in mud. This plant grows easily in salty and alkaline soils, excreting salts from its tissues via salt glands. Description Distichlis spicata is a hardy perennial with rhizome s and sometimes stolon s. It is an erect grass which occasionally approaches half a meter in height but is generally shorter. The solid, stiff stems have narrow leaves up to 10 centimeters in length, which may be crusted with salt in saline environments. This species is Plant sexuality dioecious , meaning the male flowers and female flowers grow on separate individuals. The Gynoecium pistillate inflorescence may be up to 8 centimeters long, wi ... more details
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