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| − | {{Taxobox | + | __NOTOC__{{Plantbox |
| − | | color = lightgreen | + | | name = ''Orchidaceae'' |
| − | | name = Orchids | + | | common_names = <!--- if multiple, list all, if none, leave blank --> |
| | + | | color = IndianRed |
| | | image = Haeckel Orchidae.jpg | | | image = Haeckel Orchidae.jpg |
| | + | | image_width = 180px <!--- leave as 240px if horizontal orientation photo, or change to 180px if vertical --> |
| | | image_caption = Color plate from [[Ernst Haeckel]]'s ''[[Kunstformen der Natur]]'' | | | image_caption = Color plate from [[Ernst Haeckel]]'s ''[[Kunstformen der Natur]]'' |
| − | | regnum = [[Plant]]ae | + | | regnum = Plantae |
| − | | divisio = [[Flowering plant|Magnoliophyta]] | + | | divisio = Magnoliophyta |
| − | | classis = [[Monocotyledon|Liliopsida]] | + | | classis = Liliopsida |
| − | | ordo = [[Asparagales]] | + | | ordo = Asparagales |
| − | | familia = '''Orchidaceae''' | + | | familia = Orchidaceae |
| − | | familia_authority = [[Antoine Laurent de Jussieu|Juss.]]
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| − | | subdivision_ranks = Subfamilies
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| − | | subdivision =
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| − | * [[Apostasioideae]]
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| − | * [[Cypripedioideae]]
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| − | * [[Epidendroideae]]
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| − | * [[Orchidoideae]]
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| − | * [[Vanilloideae]]
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| − | For genera, see [[list of Orchidaceae genera]].
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| | }} | | }} |
| − | '''Orchids''' ('''Orchidaceae''' family) are the largest and most diverse of the [[flowering plant]] ([[Angiospermae]]) families, with over 800 described [[genus|genera]] and 25,000 [[species]]. Some sources give 30,000 species, but the exact number is unknown since classification differs greatly in the academic world. Revisions of different genera occur on a monthly basis and this will increase with the growing use of genetic research and biochemistry. There are another 100,000+ [[hybrid]]s and [[cultivar]]s produced by [[horticulture|horticulturists]], created since the introduction of tropical species in the 19th century. The Kew ''World Checklist of Orchids'' includes about 24,000 accepted species. About 800 new species are added each year. Orchids, through their interactions with [[pollinator]]s and their [[symbiosis]] with [[Orchid mycorrhiza|orchid mycorrhizal]] fungi, are considered by some, along with the [[Poaceae|grasses]], to be examples of the most advanced (derived) floral [[evolution]] known.
| + | {{Inc| |
| | + | Orchidaceae (from the genus Orchis, an ancient name of these plants). Orchid Family. Fig. 13. Herbaceous plants of very diverse habit and structure; terrestrial, epiphytic or saprophytic, sometimes climbing; the terrestrial with fibrous roots or with thickened tuber-like roots, the epiphytic often with the base of the leaf and adjoining stem swollen, forming a pseudobulb; the saprophytic without chlorophyll; the epiphytic often with aerial hanging roots are provided with a water-absorbing layer (velamen): leaves alternate, succulent, coriaceous or membranous, linear to oval: flowers bisexual, rarely unisexual, irregular, epigynous; perianth of 6 parts, in 2 series, usually all petaloid; one petal larger, forming the lip (labellum); stamens originally 6, but all except 1 or 2 wanting, or reduced to staminodia, united with the pistil; pollen-grains compound, granular, or aggregated into masses (pollinia) which are either free in the anther or attached by a stalk to a viscid apical or stigmatic gland; carpels 3; ovary inferior, 1- or 3-celled; ovules very numerous; style united with the stamens to form the column; stigma in the front of the column, or on a projecting lobe: fruit a capsule; seeds very minute. |
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| − | All orchid species are protected for the purposes of international commerce under [[CITES]] as potentially threatened or endangered in their natural habitat, with most species listed under Appendix II. A number of species and genera are afforded protection under Appendix I, including all ''[[Paphiopedilum]]'', ''[[Phragmipedium]]'', ''[[Mexipedium]]'', ''[[Cypripedium]]'', and ''[[Selenipedium]]'' species. Many other species are protected by both international and national legislation, while hybrids are supposed to be specifically exempted, hybrid orchids are not allowed into the United States without a CITES permit. Reason that is given is that the authorities can not distinguish the difference between hybrids and species.{{Fact|date=February 2007}}
| + | This is an important family of more than 400 genera and between 6,000 and 10,000 species. Orchids are very widely distributed, except in the arctics, but are most numerous in the tropics. Those of temperate regions are mainly terrestrial; those in the tropics commonly epiphytic. The large genera are Epidendrum, 500 species; Habenaria, Dendrobium, Bulbophyllum, and Oncidium, 200-600 species each; Masdevallia, Odontoglossum, and Maxillaria, each 100 or more species. |
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| − | ==Naming==
| + | From the standpoint of the intricate and very special mechanisms evolved in order to insure cross-pollination, the orchids are the most wonderful of our insect-pollinated plants, for a detailed account see Darwin's "Fertilization of Orchids," or Kerner and Oliver's "Natural History of Plants." In general, the insect visiting the showy flower for the honey comes in contact with the sticky gland above the stigma, thereby pulling it out, along with the attached pollen masses. While the insect is going to another flower, the pollen masses dry and bend down until they are in position to strike the viscid stigma, which tears away and retains some of the pollen. The method of pollination in Cypripedium is fundamentally different. Some orchids (e.g., Catasetum) possess a sensitive explosive mechanism that forcibly ejects the pollen mass, often to the distance of 2 or 3 feet. The minute seeds of the orchids are well adapted to be disseminated by the wind and find lodgment in the crevices of the bark of trees and on other supports. |
| − | Orchids get their name from the [[Greek language|Greek]] ορχις ''orchis'', meaning "testicle", from the appearance of subterranean tuberoids of the genus ''[[Orchis]]''. The word "orchis" was first used by [[Theophrastos]] ([[372 BC|372]]/[[371 BC|371]] – [[287 BC|287]]/[[286 BC]]), in his book "De historia plantarum" (The natural history of plants). He was a student of [[Aristotle]] and is considered the father of [[botany]] and [[ecology]].
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| − | ==Appearance and Structure==
| + | Orchids are divided into large groups as follows: |
| − | Orchids like the [[Grass|grasses]] and the [[palm]]s, which they resemble in some ways—for instance the form of their leaves—are [[monocotyledon]]s. They have one [[cotyledon]], or embryo leaf, in contrast to the two of most flowering plants. | |
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| − | Orchids are [[cosmopolitan distribution|cosmopolitan]] in distribution, occurring in every [[Habitat (ecology)|habitat]], except [[Antarctica]] and deserts. The great majority are to be found in the [[tropics]], mostly [[Asia]], [[South America]] and [[Central America]]. They are found above the Arctic Circle, in southern [[Patagonia]] and even on [[Macquarie Island]], close to Antarctica.
| + | Group I. [[Diandrae]]. The two lateral stamens of the inner whorl fertile, the dorsal of the outer whorl staminodial or fruitful, the others absent. Cypripedium, Selenipedium, Paphiopedilum, and others. |
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| − | The following list gives a rough overview of their distribution: | + | Group II. [[Monandrae]]. The dorsal stamen of the outer whorl fruitful, all the others wanting. By far the majority of the species belong here. Subgroup I. Pollinia connected by caudicles with a gland at base of anther near stigma. Subgroup 2. Pollen without caudicles or with these attached to a gland at apex of anther. |
| − | * Eurasia: 40–60 genera
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| − | * North America: 20–30 genera
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| − | * tropical America: 300–350 genera
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| − | * tropical Africa: 125–150 genera
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| − | * tropical Asia: 250–300 genera
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| − | * Oceania: 50–70 genera
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| − | Orchids can be grouped according to the way they retrieve nutrients:
| + | The family is very distinct and easily distinguished. Its only near relatives are the Burmanniaceae. The peculiar structure of the stamens and pistil, together with the minute exalbuminous seeds are distinctive. |
| − | * A majority of species are [[perennial]] [[epiphyte]]s; they are found in [[tropical moist broadleaf forests]] or mountains and subtropics. These are anchored on other plants, mostly [[tree]]s, someti
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| − | mes [[shrub]]s. However, they are not [[parasite]]s.
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| − | * A few are [[lithophyte]]s, similar to epiphytes but growing naturally on rocks or on very rocky soil. They derive their nutrients from the atmosphere, rain water, litter, [[humus]], and even their own dead tissue.
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| − | * Others are [[terrestrial plant]]s. They grow in the soil or in the loose substrate atop the ground and obtain their nutrients from the soil or the substrate. This group includes nearly all temperate orchids.
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| − | * Some lack [[chlorophyll]] and are [[myco-heterotrophs]] (formerly incorrectly called [[saprophytes]]). These achlorophyllous orchids have an ectomycorrhizal relationship, i.e. they are completely dependent on soil [[fungi]] feeding on decaying plant matter (usually fallen [[leaf|leaves]]) to provide them with nutrients. Typical examples include the [[Bird's-nest Orchid]] (''Neottia nidus-avis'') and Spotted Coral-root (''[[Corallorrhiza maculata]]'').
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| − | Most advanced orchids have these five basic features:
| + | The Orchidaceae is perhaps the most important family from the standpoint of ornamental gardening. To grow these singular, fantastic, showy, and often sweet-scented flowers has in recent years become almost a craze. It is estimated that, whereas Linnaeus knew but a dozen exotic orchids, at the present day more than 2,500 are known to English horticulturists. Plants in the family useful for other purposes are few. The most important is vanilla, derived from the capsule of Vanilla planifolia of Mexico, and now widely cultivated in the tropics. Faham (Angraecum fragrans of Bourbon) has a fragrant, bitter-almond-like taste: the leaves are used for indigestion and tuberculosis, and are known as Bourbon tea. Salep is derived from the roots of various terrestrial orchids of the Mediterranean region. The roots of helleborine (Epipactis latifolia) are used for rheumatism. The root of Spiranthes diuretica of Chile is renowned as a diuretic. The flowers of Habenaria conopsea are used for dysentery. Spiranthes autumnalis and Habenaria bifolia are said to be aphrodisiac. The roots of Cypripedium parviflorum var. pubescens are frequently used in America as a substitute for valerian.{{SCH}} |
| − | *The presence of a [[column (botany)|column]], also called gynostemium
| + | }} |
| − | *The flower is [[symmetry (biology)#Bilateral symmetry|bilaterally symmetric]] ([[zygomorphic]])
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| − | *The [[pollen]] are glued together into the [[pollinium|pollinia]], a mass of waxy pollen on filaments.
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| − | *The [[seed]]s are microscopically small, lacking [[endosperm]] (food reserves) in the overall majority of the species. There are notable exceptions, such as ''[[Disa (orchid)|Disa]] cardinalis'', whose seeds may grow to a length of 1.1 mm. Seeds of ''[[Vanilla (orchid)|Vanilla]]'' may weigh 20 times or more than that of other orchids. They and their surrounding pulp within the seed pod are used in the food industry as the extremely popular flavoring "vanilla extract".
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| − | *The seeds can, under natural circumstances, only germinate in [[symbiosis]] with specialized fungi. Under artificial circumstances, however, germination is possible "''in vitro''" on sterile substrates of [[agar]] in specialized laboratories. Germinating seeds in agar, usually done in flasks, is an advanced technique, requiring sterility at all costs. It takes anywhere from one–up to five to ten years for an orchid seedling to mature. An alternative type artificial germination, however, is done by cultivating the fungus and sowing the seeds on them. This is called in-vitro symbiotic culture and is used most commonly for terrestrial orchids.
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| − | ==Leaves== | + | ==Genera== |
| − | [[image:Dendrobium crumenatum.jpg|thumb|250px|right|This small orchid demonstrates a typical [[zygomorphic]] flower with three petal-like [[sepal]]s (top, lower right, lower left), two normal [[petal]]s on either side of the dorsal (upper) sepal, and the [[labellum]], a modified lower petal in three parts surrounding and below the shiny column.]] | + | [[image:Dendrobium crumenatum.jpg|thumb|250px|This small orchid demonstrates a typical [[zygomorphic]] flower with three petal-like [[sepal]]s (top, lower right, lower left), two normal [[petal]]s on either side of the dorsal (upper) sepal, and the [[labellum]], a modified lower petal in three parts surrounding and below the shiny column]] |
| − | Orchids have simple [[Leaf|leaves]] with parallel [[vein]]s. Their shape is highly variable between species; ovate, lanceolate, or orbiculate. Their size and shape can be an aid in identifying the orchid, since it reflects the taxonomic position. The leaves can be enormous or minute, or they can even be lacking (as in the [[Ghost Orchid]] (''Dendrophylax lindenii''), a mycoheterotrophic species, and ''[[Aphyllorchis]]'' and ''[[Taeniophyllum]]'', which depend on their roots, which contain chlorophyll for [[photosynthesis]]).
| + | The taxonomy of this family is in constant flux, as [[DNA]] studies give new information. |
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| − | The structure of the leaves corresponds to the specific habitat of the orchid. Species that typically bask in sunlight, or grow on sites which can be occasionally very dry, have thick, leathery leaves. The [[lamina]]s are covered by a waxy [[cuticle]]. These retain their necessary water supply. Shade species, on the other hand, have tall, thin leaves. They cannot tolerate a drop in atmospheric humidity or exposure to direct sunlight. Between these two extremes, there is a whole range of intermediate forms.
| + | Subfamilies |
| − | | + | * [[Apostasioideae]] |
| − | The leaves of most orchids live on, attached to their [[pseudobulbs]], for several years. Some species, especially those with plicate leaves, shed their aged leaves annually, through an articulation between the lamina and the [[Petiole (botany)|petiole]] sheath, and develop new leaves together with new pseudobulbs (as in the genus ''[[Catasetum]]'').
| + | * [[Cypripedioideae]] |
| − | | + | * [[Epidendroideae]] |
| − | The leaves of some species can be most beautiful. The leaves of the ''Macodes sanderiana'', a semiterrestrial or lithophyte, show a sparkling silver and gold veining on a light green background. The cordate leaves of ''Psychopsiella limminghei'' are light brownish green with maroon-puce markings, created by flower pigments. The attractive mottle of the leaves of [[Lady's Slipper]]s from temperate zones (''[[Paphiopedilum]]'') is caused by uneven distribution of chlorophyll. Also ''Phalaenopsis schilleriana'' is a lovely pastel pink orchid with leaves spotted dark green and light green. The Jewel Orchid (''Ludisia discolor'') is grown more for its colorful leaves than its fairly inconspicuous white flowers.
| + | * [[Orchidoideae]] |
| − | | + | * [[Vanilloideae]] |
| − | ==Stem==
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| − | The stem of an orchid determines the habit of the species. Each type of stem can grow in one of these two ways:
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| − | *[[monopodial]] ("one-footed") growth. The new shoots grow upwards from a single stem, originating in the end bud of the old shoots. It then produces leaves and flowers along this stem. The stem of these orchids can reach a length of several meters (as in the genera ''[[Vanda]]'' and ''[[Vanilla]]''). | |
| − | *[[sympodial]] ("many-footed") growth. The plant produces a series of adjacent shoots which grow to a certain size, bloom, then stop growing, to be replaced by the next growth. Plants of this type grow laterally rather than vertically, following the surface of their support. The growth continues by development of new leads (with their own leaves and roots) sprouting from or next to those of the previous year (as in the genus ''[[Cattleya]]''). While this lead is developing, the rhizome may start its growth again, this time from an 'eye', or undeveloped bud, thereby causing the rhizome to branch.
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| − | ==Plant thallus and roots==
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| − | [[image:Pseudobulbs_new.jpg|thumb|right|[[Pseudobulb]]s of an [[epiphytic]] orchid]]
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| − | All orchids are [[perennial]] herbs, lacking any permanent [[wood]]y structure.
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| − | *Some orchids are terrestrial, growing rooted in the [[soil]]. Terrestrial orchids may be [[rhizome|rhizomatous]], forming '''[[corm]]s''' or '''[[tuber]]s'''. These act as storage organs for food and water. The root caps of terrestrials are smooth and white. Terrestrials are mostly found in colder climates.
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| − | *A great many orchids are [[epiphyte]]s, which do not require soil and use trees for support. They occur in warmer regions. Epiphytic orchids have modified [[aerial root]]s and, in the older parts of the root, an [[Epidermis (botany)|epidermis]] modified into a spongy, water-absorbing '''[[velamen]]''', which can have a silvery-gray, white or brown appearance. The cells of the root epidermis grow at a right angle to the axis of the root. This allows them to get a firm grasp on their support. These roots can sometimes be a few meters long, in order to take up as much moisture as possible. Nutrients mainly come from animal droppings on their supporting tree that are washed down when it rains. The aerial roots of epiphytes that lack leaves have an additional function. They contain chlorophyll and take up [[carbon dioxide]].
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| − | *Several species are [[lithophyte]]s, especially in rocky mountain ranges in [[Australia]] and [[Tasmania]], central [[Brazil]] and [[Africa]].
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| − | The base of the stem of sympodial epiphytes, or in some species essentially the entire stem, may be thickened to form what is called a ''',[[pseudobulb]]'''. These contain nutrients and water for drier periods. Pseudobulbs have a smooth surface with lengthwise grooves. They typically stay alive for five or six years. They look on the inside more like a corm than the embryonal stage of leaf sheaths. They have different sizes and shapes. They can be conical or oblong. In the Black Orchids (''[[Bulbophyllum]]''), the pseudobulbs are no longer than 2 mm. The largest orchid in the world, the [[Giant Orchid]] (''Grammatophyllum speciosum''), has pseudobulbs with lengths of 2–3 m. When the orchid has aged and the pseudobulb has shed its leaves, the pseudobulb becomes dormant and is called a '''backbulb'''. The next year's pseudobulb then takes over, exploiting the last reserves of the backbulb. Eventually, the backbulb also dies off, having given life to newer growths. At the end of the pseudobulb typically appear one or two leaves, though there may be up to a dozen or more. Some ''[[Dendrobium]]'' have long, canelike pseudobulbs with short, rounded leaves over the whole length. Some orchids have hidden or extremely small pseudobulbs hidden completely inside leaves.
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| − | Some sympodial terrestrials, such as ''Orchis'' and ''[[Ophrys]]'', have two subterranean tubers (more like [[tuberous root]]s) between the [[root]]s. One is used as a food reserve for wintery periods, and provides for the development of the other pseudobulb, from which visible growth develops.
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| − | In warm and humid climates, many terrestrial orchids do not need pseudobulbs.
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| − | ==Orchid flowers==
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| − | [[Image:Calopogon.web.jpg|thumb|right|250px|Calopogon orchid]]
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| − | [[Image:Rainforestorchid.jpg|thumb|right|250px|Wild orchid from Sumatran Rainforest]]
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| − | There are many types of [[specialization]]s within the Orchidaceae. Best known are the seemingly endless structural variations in the [[flower]]s that encourage [[pollination]] by particular species of [[insect]]s, [[bat]]s, or [[bird]]s.
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| − | Most African orchids are white, while Asian orchids are often multicolored. Some orchids only grow one flower on each stem, others sometimes more than a hundred together on a single spike.
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| − | The typical orchid flower is [[zygomorphic]], i.e. [[symmetry (biology)#Bilateral symmetry|bilaterally symmetric]]. Notable exceptions are the genera ''Mormodes'', ''Ludisia'' and ''Macodes''.
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| − | The flowers grow on [[raceme]]s or [[panicle]]s. These can be :
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| − | * basal (i.e. produced from the base of the pseudobulb, as in ''[[Cymbidium]]'') | |
| − | * apical (i.e. produced from the apex of the orchid, as in ''[[Cattleya]]'') | |
| − | * or axillary (i.e. coming from a node between the leaf axil and the plant axis, as in ''[[Vanda]]''). | |
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| − | The basic orchid flower is composed of three [[sepal]]s in the outer whorl, and three [[petal]]s in the inner whorl. The medial petal is usually modified and enlarged (then called the '''[[labellum]]''' or lip), forming a platform for pollinators near the center of the [[corolla]]. Together, except the lip, they are called '''[[tepal]]s'''.
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| − | Sepals form the exterior of the bud. They are green in this stage, but sometimes, if the orchid blossom is, for example, purple, the buds can show a purple tint. When the flower opens, the sepals become intensely colored. Sepals may mimic petals such as in some phalaenopsis or be completely distinct. In many orchids, the sepals are mutually different and generally resemble the petals. It is not always easy to distinguish sepals and petals. The normal form can be found in ''[[Cattleya]]'', with three sepals forming a triangle. But in Venus Slippers (''Paphiopedilum'') the lower two sepals are concrescent (fused together into a [[synsepal]]), while the lip has taken the form of a slipper. In ''[[Masdevallia]]'' all the sepals are fused into a [[calyx (flower)|calyx]]. In an example like this the sepals are very prominent, especially in lycaste orchids, the actual petals become diminished and inconspicuous.
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| − | The [[reproductive organ]]s in the center ([[stamen]]s and [[carpel|pistil]]) have adapted to become a cylindrical structure called the [[column (botany)|column]] or gynandrium. On top of the column lies the [[Carpel|stigma]], the vestiges of stamens and the [[Pollinium|pollinia]], a mass of waxy [[pollen]] on filaments. These filaments can be a '''[[caudicle]]''' (as in ''[[Habenaria]]'') or a '''[[stipe (botany)|stipe]]''' (as in ''[[Vanda]]''). These filaments hold the pollinia to the '''[[viscidium]]''' (sticky pad). The pollen are held together by the [[alkaloid]] [[viscine]]. This viscidium adheres to the body of a visiting insect. The type of pollinia is useful in determining the genus. On top of the pollinia is the '''[[anther cap]]''', preventing self-pollination. At the upper edge of the stigma of single-anthered orchids, in front of the anther cap, is the '''[[rostellum]]''', a slender beaklike extension.
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| − | ==Reproduction==
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| − | [[Image:Ophrys-bombyliflora.web.jpg|thumb|right|250px|[[Bumblebee Orchid]] (''Ophrys bombyliflora'')]]
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| − | It is in the variety and the refinement of their [[Reproduction|reproductive]] methods that orchids truly amaze. On many orchids, the lip ([[labellum]]) serves as a landing pad for flying insects. The labellum is sometimes adapted to have a color and shape which attracts particular male insects via mimicry of a receptive female insect. Some orchids are reliant solely on this deception for pollination. After pollination, the epigynous [[ovary (plants)|ovary]] starts developing and produces a many-seeded [[capsule (fruit)|capsule]].
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| − | *The Lady's Slipper (''[[Paphiopedilum]]'') has a deep pocket that traps visiting insects, with just one exit. Passage through this exit leads to [[pollinium|pollinia]] being deposited on the insect. | |
| − | *Many neotropical orchids are pollinated by male [[euglossini|orchid bees]], which visit the flowers to gather volatile chemicals they require to synthesize [[pheromone|pheromonal]] attractants. Each type of orchid places the pollinia on a different body part of a different species of bee, so as to enforce proper cross-pollination.
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| − | *A Eurasian genus ''Ophrys'' has some species that look and smell so much like female [[bumblebee]]s that male bees flying nearby are irresistibly drawn in and attempt to mate with the flower, such as with the [[Bumblebee Orchid]] (''Ophrys bombyliflora''). The viscidium, and thus pollinia, stick to the head or the abdomen of the bumblebee. On visiting another orchid of the same species, the bumblebee pollinates the sticky stigma with the pollinia. The filaments of the pollinia have, during transport, taken such position that the waxy pollen are able to stick in the second orchid to the stigma, just below the rostellum. Such is the refinement of the reproduction. If the filaments had not taken the new position on the bee, the pollinia could not have pollinated the original orchid. Other species of ''Ophrys'' are mimics of different bees or wasps, and are also pollinated by males attempting to mate with the flowers, and other orchid genera practice similar deception.
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| − | *An underground orchid in Australia, ''[[Rhizanthella slateri]]'', never sees the light of day, but depends on [[ant]]s and other terrestrial insects to pollinate it.
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| − | *Many ''[[Bulbophyllum]]'' species stink like [[Decomposition|rotting]] [[carcass]]es, and the [[Fly|flies]] they attract assist their reproduction.
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| − | *''Catasetum saccatum'', a species discussed briefly by [[Charles Darwin|Darwin]] actually launches its viscid pollen sacs with explosive force, when an insect touches a [[seta]]. He was ridiculed for reporting this by the naturalist [[Thomas Huxley]].
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| − | *Some ''[[Phalaenopsis]]'' species in [[Malaysia]] are known to use subtle weather cues to coordinate mass flowering.
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| − | *Some ''Phalaenopsis'', ''Dendrobium'' and ''Vanda'' species produce [[keiki]], offshoots or plantlets formed from one of the [[node (botany)|node]]s along the [[Plant stem|stem]], through the accumulation of growth hormones at that point.
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| − | The filaments of the pollinia of some orchids dry up if they haven’t been visited by an insect. This way, the waxy pollen falls on the stigma causing the orchid to self-fertilize.
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| − | *''[[Holcoglossum]] amesianum'', native to China's [[Yunnan]] province, reproduces in a hermaphroditic manner, fertilizing itself by rotating its anther and insert it into the flower's stigma cavity. This mode of pollination is likely due to the lack of wind and insects in the region where this species grows. The [[Bee orchid]] uses a similar method of selfpollination.
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| − | ==Fruits and seeds==
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| − | [[Image:Kapselquerschnitte Orchideen.png|thumb|right|200px|cross-section of an orchid capsule, showing 3 or 6 longitudinal slits]]
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| − | The orchid [[ovary (plants)|ovary]] is always inferior (located behind the flower), three-[[carpel]]ate and one or three-partitioned, with parietal [[placenta]]tion (but axile in the [[Apostasioideae]]).
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| − | If pollination was successful, the sepals and petals fade and wilt but they remain attached to the ovary. The epigynous ovary typically develops into a [[capsule (fruit)|capsule]] that is [[dehiscent]] by 3 or 6 longitudinal slits, while remaining closed at both ends. The [[ripe]]ning of a capsule can take 2–18 months. The microscopic [[seed]]s are very numerous (over a million per capsule in most species). They blow off after ripening like dust particles or spores, barely visible to the human eye. Since they lack [[endosperm]], they must enter symbiotic relationship with mycorrhizal fungi to germinate. These fungi provide the necessary nutrients to the seeds.
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| − | [[Image:Random 010e.jpg|thumb|left|150px|An orchid seed capsule]]
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| − | All orchid species are reliant upon [[Orchid mycorrhiza|mycorrhizal]] associations with various [[basidiomycete]]ous [[fungi]] to complete their lifecycle. Although all orchids are mycoheterotrophic during germination, some achlorophyllous (lacking chlorophyll) species are entirely dependent upon these fungi for nutrients. In general, orchid mycorrhizal fungi [[Decomposition|decompose]] organic matter and subsequently [[translocate]] the obtained nutrients via their [[hyphae]] to the orchid. Because most orchid seeds are extremely tiny with no food reserves ([[endosperm]] lacking), they will not germinate without such a [[symbiosis|symbiont]] to supply nutrients in the wild. Some fungi continue to live in the roots of the adult orchid. This enables an orchid such as ''[[Neottia nidus-avis]]'' to function without chlorophyll. The chance for a seed to meet a fitting fungus is very small. Of all the seeds released, only a minute fraction grow into new orchids. This process can take years; in some cases up to fifteen years.
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| − | [[Horticultural]] techniques have been devised for germinating seeds on a nutrient-containing gel, eliminating the requirement of the fungus for germination, and greatly aiding the propagation of rare and endangered species.
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| − | ==Orchids in commerce==
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| − | [[Image:Orchid.jpg|thumb|left|250px|Phalaenopsis hybrid]]
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| − | One orchid genus, ''Vanilla'', is commercially important, used as a foodstuff flavoring, the source of [[vanilla]]. The underground tubers of terrestrial orchids are ground to a powder and used for cooking, such as in the hot beverage [[salep]] or the so-called "fox-testicle ice cream" [[salepi dondurma]]. The scent of orchids is frequently used by [[Perfume|perfumists]] (using [[Gas-liquid chromatography]]) to identify potential fragrance chemicals. With these exceptions, orchids have virtually no commercial value other than for the enjoyment of the flowers (see also [[Botanical orchids]]).
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| − | There are a great number of [[tropical]] and [[subtropical]] orchids, and these are the most commonly known, as they are available at nurseries and through orchid clubs across the world. There are also quite a few orchids which grow in colder climates, although these are less often seen on the market. Temperate species available at nurseries include ''[[Ophrys apifera]]'' (bee orchid), ''[[Gymnadenia conopsea]]'' (fragrant orchid), ''[[Anacamptis pyramidalis]]'' (pyramidal orchid) and ''[[Dactylorhiza fuchsii]]'' (common spotted orchid).
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| − | The family of orchids is remarkably diverse. The plants found in "casual" culture, such as ''[[Phalaenopsis]]'', ''[[Cattleya]]'', ''[[Dendrobium]]'', and so forth, represent a tiny fraction of the thousands of species of orchids. Also within the Orchidaceae are "[[leaf]]less" orchids, which often appear as nothing more than masses of [[root]]s, achlorophyllous orchids that are entirely reliant upon their mycorrhizal symbiont for their nutrition, "jewel" orchids with foliage that is as pretty as their flowers, and so many others that are capable of affecting the most dedicated of growers very deeply. Ranging in size from tiny moss-like ''[[Pleurothallis]]'' species to massive (7 m) ''[[Grammatophyllum]]'' species in [[New Guinea]], their beauty and sophistication have captivated many.
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| − | The National Orchid Garden in the [[Singapore]] [[Sing
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| − | apore Botanic Gardens|Botanic Gardens]] is considered by some to be among the finest collections of orchids in cultivation open to the public. In [[2004]], [[Taiwan]] established the [[Taiwan Orchid Plantation]], a science-based [[industrial park]], to develop its commercial orchid exports in the future. See also [[botanical orchids]].
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| − | Orchids, like [[tulip]]s, have become a major market throughout the world. Buyers now bid hundreds of dollars on new hybrids or improved ones. Because of their apparent ease in hybridization, they are now becoming one of the most popular cut-flowers on the market. Though orchid hybridization has been happening for many years, only recently has new technology made it into what it is.
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| − | ==Vanilla==
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| − | [[Image:Vanilla fragrans 2.jpg|thumb|250px|Vanilla fruit]]
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| − | [[Vanilla]], ''Vanilla planifolia'' (and two other ''Vanilla'' species less commonly grown), is the only orchid which is grown for any other use besides its beauty (with a few minor exceptions). Vanilla was first cultivated in [[Central America]] where it was used, like today, as a flavoring. Vanilla cultivation was introduced to other parts of the world in the 1800s and it is now an important crop in much of the tropics. [[Madagascar]] is the leading producer, producing in 2005, 3 million metric tons (of a world total of 7.3 million metric tons).
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| − | The [[Coca-Cola]] Company is the world's largest user of vanilla. Besides its use as a flavoring, it is also used in fragrances and perfumes.
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| − | Vanilla is a very labor intensive crop since the flowers have to be pollinated by hand. It is considered as one of the most profitable enterprises for small family farms. [http://news.bbc.co.uk/1/hi/business/3017876.stm]
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| − | ==Taxonomy==
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| − | The taxonomy of this family is in constant flux, as [[DNA]] studies give new information. An in-depth treatment of the taxonomy is given in [[Taxonomy of the Orchid family]].
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| | The following genera have been described (for a full list, see [[List of Orchidaceae genera]] with more than 800 genera and many pictures): | | The following genera have been described (for a full list, see [[List of Orchidaceae genera]] with more than 800 genera and many pictures): |
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| | ''[[Rhynchostylis]]''; | | ''[[Rhynchostylis]]''; |
| | ''[[Saccolabium]]''; | | ''[[Saccolabium]]''; |
| − | ''[[Sarcochilus]]' | + | ''[[Sarcochilus]]''; |
| − | '; | |
| | ''[[Satyrium]]''; | | ''[[Satyrium]]''; |
| | ''[[Selenipedium]]''; | | ''[[Selenipedium]]''; |
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| | ''[[Zygopetalum]]''. | | ''[[Zygopetalum]]''. |
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| − | ==See also== | + | ==Gallery== |
| − | *[[Moyobamba]] - the 'City of Orchids', which has some 3,500 species of orchid native to the area
| + | {{photo-sources}}<!-- remove this line if there are already 3 or more photos in the gallery --> |
| − | *[[Semi-hydroponic for growing orchids]]
| + | |
| | + | <gallery> |
| | + | image:Pseudobulbs_new.jpg|[[Pseudobulb]]s of an [[epiphytic]] orchid] |
| | + | Image:Calopogon.web.jpg|Calopogon orchid |
| | + | Image:Rainforestorchid.jpg|Wild orchid from Sumatran Rainforest |
| | + | Image:Ophrys-bombyliflora.web.jpg|[[Bumblebee Orchid]] (''Ophrys bombyliflora'') |
| | + | Image:Kapselquerschnitte Orchideen.png|cross-section of an orchid capsule, showing 3 or 6 longitudinal slits |
| | + | Image:Random 010e.jpg|An orchid seed capsule |
| | + | Image:Orchid.jpg|Phalaenopsis hybrid |
| | + | Image:Vanilla fragrans 2.jpg|Vanilla fruit |
| | + | </gallery> |
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| | ==References== | | ==References== |
| − | | + | *[[Standard Cyclopedia of Horticulture]], by L. H. Bailey, MacMillan Co., 1963 |
| − | *Batygina, T. B., Bragina, E. A., and Vasilyeva, E. 2003. ''The reproductive system and germination in orchids''. Acta Biol. Cracov. ser. Bot. 45: 21-34. | |
| − | *Berg Pana, H. 2005. ''Handbuch der Orchideen-Namen. Dictionary of Orchid Names. Dizionario dei nomi delle orchidee''. Ulmer, Stuttgart
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| − | *Kreutz, C. A. J. 2004. ''Kompendium der Europaischen Orchideen. Catalogue of European Orchids''. Kreutz Publishers, Landgraaf, Netherlands
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| − | * D. Lee Taylor and Thomas D. Bruns : ''Ectomycorrhizal mutualism by two nonphotosynthetic orchids''; Proc. Natl. Acad. Sci. USA; Vol. 94, pp. 4510-4515, April 1997 ([http://plantbio.berkeley.edu/~bruns/papers/taylor1997b.html on line]).
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| | ==External links== | | ==External links== |
| − | *[http://www.anbg.gov.au/cpbr/orchids/index.html Revealing the secret life of orchids ( Centre for plant biodiversity research - CSIRO and Botanic Gardens Australia )] | + | *{{wplink}} |
| − | *[http://www.apstas.com/groundorchids.htm Tasmanian terrestrial orchids (Hobart District Group of The Australian Plants Society)]
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| − | {{commonscat|Orchidaceae}} | |
| − | *[http://www.kew.org/wcsp/home.do Kew checklist]
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| − | * [http://www.digitalcloseups.com Orchid Picture Gallery]
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| − | *[http://www.ocos.net Orange County (California) Orchid Society]
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| − | *[http://www.orchidspecies.com/index.htm Orchid Photo Encyclopedia]
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| − | *[http://news.nationalgeographic.com/news/2004/03/0308_040308_cheatingorchids.html#main Report on pollination tactics by orchids]
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| − | *[http://www.orchideen.at/english/frames_e.htm Austrian Orchid Society]
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| − | *[http://www.orchidean.com/videos Orchid Videos]
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| − | *[http://www.orchidworks.com/ OrchidWorks] - a photo album and overview of a variety of orchids
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| − | *[http://orchid.unibas.ch/ Swiss Orchid Foundation at the Herbarium Jany Renz]
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| − | *[http://www.nativeorchid.org/ Native Orchid Conservation Inc]
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| − | *[http://www.pharmanatur.com/orchid.htm Orchids of Europe]
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| − | *[http://www.mayumihashi.com/blog-en/ Peruvian Orchids] - Mayumi Hashi, a botanical illustrator's report on a trip to Peru, which was partly funded by the [[Royal Horticultural Society]] (RHS).
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| − | *[http://www.fieldmuseum.org/vanishing_treasures/V_Wwaling.htm Waling-waling, an endangered orchid]
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| − | *[http://www.coloridellamurgia.it/gall/schedebotorc/index.htm Wild orchids of "Alta Murgia" (Apulia - Southern Italy)]
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| − | *[http://www.alpine-plants-jp.com/art/index_ranka.htm Wild orchid of Japan] - Flavon's art gallery
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| − | [[Category:Flowers]] | + | {{stub}} |
| | + | [[Category:Categorize]] |
| | [[Category:Plant families]] | | [[Category:Plant families]] |
| − | [[Category:Orchids| ]]
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