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Potamogeton × Angustifolius
''Potamogeton'' × ''angustifolius'' is a hybrid pondweed between '' Potamogeton gramineus'' and ''Potamogeton lucens'', known as long-leaved pondweed. It is widespread in rivers and lakes except where the water is very soft. Description ''Potamogeton'' × ''angustifolius'' is a hybrid between shining pondweed ''Potamogeton lucens'' and various-leaved pondweed '' Potamogeton gramineus''. It is a perennial, growing from robust rhizomes. The stems are variable: slender to robust, terete, and branching, usually reaching 1.2 m but rarely up to 2m. The submerged leaves are reduced to phyllodes at the base of the stem, but elsewhere are broad and translucent, yellowish to dark green, sometimes with a pinkish tinge. The leaves measure 50-130 × 10–25 mm on the stems and main branches, but may be much smaller on the side branches; they have 4-5 (rarely 6) veins either side of the midrib and are usually sessile but some clones may have a few petiolate leaves. Turions are absent. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Gramineus
''Potamogeton gramineus'' is a species of aquatic plant known by the common name various-leaved pondweed, variableleaf pondweed, grass-leaved pondweed or grassy pondweed, native to the northern hemisphere where it grows in shallow, clean water. Description This is an aquatic perennial growing from a creeping rhizome that anchors in wet substrate. It produces thin, cylindrical, heavily branching stems usually less than a metre in length. The submerged leaves are sessile, relatively narrow, typically 40–90 mm long and 5–12 mm wide along the main stem but smaller on the side branches. They are translucent and pale green with a white midrib, and finely toothed. Floating leaves are more oval in shape, 20–70 mm long by 7–34 mm wide, and borne on long petioles. The inflorescence is a short spike of many flowers arising from the water on a stout peduncle. This species readily hybridizes with many other species of '' Potamogeton''. Hybrids have been record ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Lucens
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The leav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terete
Terete is a term in botany used to describe a cross section (geometry), cross section that is circular, or like a distorted circle, with a single surface wrapping around it.Lichen Vocabulary, Lichens of North America Information, Sylvia and Stephen Sharnoff/ref> That is usually contrasted with cross-sections that are flattened, with a distinct upper surface that is different from the lower surface. The cross-section of a branch in a tree is somewhat round, so the branch is terete. The cross section of a normal leaf has an upper surface, and a lower surface, so the leaf is not terete. However, the fleshy leaves of succulents are sometimes terete. Fruticose lichens are terete, with a roughly circular cross section and a single wrap-around skin-like surface called the cortex (botany), cortex, compared to foliose lichens and crustose lichens, which have a flattened cross section with an upper surface that is distinct from the lower surface. Plants and lichens may also be described ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllode
Phyllodes are modified petiole (botany), petioles or leaf stems, which are leaf-like in appearance and function. In some plants, these become flattened and widened, while the leaf itself becomes reduced or vanishes altogether. Thus the phyllode comes to serve the purpose of the leaf. Some important examples are ''Euphorbia royleana'' which are cylindrical and ''Opuntia'' which are flattened. They are common in the genus ''Acacia'', especially the Australian species, at one time put in ''Acacia'' subg. ''Phyllodineae''. Sometimes, especially on younger plants, partially formed phyllodes bearing reduced leaves can be seen. The illustration (to the right) of ''Acacia suaveolens'' from ''Novae Hollandiae plantarum specimen'' shows the juvenile true leaves, together with the developing phyllodes, and the phyllodes of the mature plant. The genus, ''Daviesia'', in the family Fabaceae, is characterised in part by the plants having phyllodes. File:Acacia suaveolens 9064505997 9f14f5f117 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sessile (botany)
In botany, sessility (meaning "sitting", in the sense of "resting on the surface") is a characteristic of plant organs such as flowers or leaves that have no stalk. Plant parts can also be described as subsessile, that is, not completely sessile. A sessile flower is one that lacks a pedicel (flower stalk). A flower that is not sessile is pedicellate. For example, the genus ''Trillium'' is partitioned into multiple subgenera, the sessile-flowered trilliums ( ''Trillium'' subgen. ''Sessilia'') and the pedicellate-flowered trilliums. The term "sessility" is also used in mycology to describe a fungal fruit body that is attached to or seated directly on the surface of the substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (aquatic environment), the earthy material that exi ..., lacking a supporting stipe or pedicel. Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petiole (botany)
In botany, the petiole () is the stalk that attaches the leaf blade to the Plant stem, stem. It is able to twist the leaf to face the sun, producing a characteristic foliage arrangement (spacing of blades), and also optimizing its exposure to sunlight. Outgrowths appearing on each side of the petiole in some species are called stipules. The terms wikt:petiolate, petiolate and wikt:apetiolate, apetiolate are applied respectively to leaves with and without petioles. Description The petiole is a stalk that attaches a leaf to the plant stem. In petiolate leaves the leaf stalk may be long (as in the leaves of celery and rhubarb), or short (for example basil). When completely absent, the blade attaches directly to the stem and is said to be Sessility (botany), sessile or apetiolate. Subpetiolate leaves have an extremely short petiole, and may appear sessile. The broomrape family Orobanchaceae is an example of a family in which the leaves are always sessile. In some other plant group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turion (botany)
A turion (from Latin turio meaning "shoot") is a type of bud that is capable of growing into a complete plant. A turion may be an underground bud. Many members of the genus '' Epilobium'' are known to produce turions at or below ground level. Some aquatic plant species produce overwintering turions, especially in the genera '' Potamogeton'', '' Myriophyllum'', '' Aldrovanda'' and '' Utricularia''. These plants produce turions in response to unfavourable conditions such as decreasing day-length or reducing temperature. They are derived from modified shoot apices and are often rich in starch and sugar Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose Glucose is a sugar with the Chemical formula#Molecular formula, molecul ...s enabling them to act as storage organs. Although they are hardy ( frost resistant), it is probable that their principal adap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a main axis (Peduncle (botany), peduncle) and by the timing of its flowering (determinate and indeterminate). Morphology (biology), Morphologically, an inflorescence is the modified part of the Shoot (botany), shoot of spermatophyte, seed plants where flowers are formed on the axis of a plant. The modifications can involve the length and the nature of the internode (botany), internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes. One can also define an inflorescence as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern. General characteristics Inflorescences are described by many different charact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peduncle (botany)
In botany, a peduncle is a stalk supporting an inflorescence or a solitary flower, or, after fecundation, an infructescence or a solitary fruit. The peduncle sometimes has bracts (a type of cataphyll) at nodes. The main axis of an inflorescence above the peduncle is the rachis, which hosts flowers (as opposed to directly on the peduncle). When a peduncle arises from the ground level, either from a compressed aerial stem or from a subterranean stem (rhizome, tuber, bulb, corm), with few or no bracts except the part near the rachis or receptacle, it is referred to as a scape. The acorns of the pedunculate oak are borne on a long peduncle, hence the name of the tree. See also *Pedicel (botany) *Scape (botany) In botany, a scape is a peduncle arising from a subterranean or very compressed stem, with the lower internodes very long and hence few or no bracts except the part near the rachis or receptacle. Typically it takes the form of a long, leafl ... Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton X Babingtonii F
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The leave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jan Svatopluk Presl
Jan Svatopluk Presl (4 September 1791 – 6 April 1849) was a Czech natural scientist. He was the brother of botanist Carl Borivoj Presl (1794–1852). The Czech Botanical Society commemorated the two brothers by naming its principal publication ''Preslia'' (founded in 1914). He is the author of Czech scientific terminology of various branches of science, including the Czech chemical nomenclature. He was the co-author of an important Czech taxonomic work, '' O Přirozenosti Rostlin''. The brothers co-edited the exsiccata series ''Vegetabilia cryptogamica Boëmiae collecta a Joanne et Carolo Presl''. Selected publications * * See also * Carl Borivoj Presl Carl Borivoj Presl (; 17 February 1794 – 2 October 1852) was a Czech botanist. Biography Presl lived his entire life in Prague, and was a professor of botany at the University of Prague (1833–52). [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
