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49-578: Gramineae  Juss. Poaceae ( / p oʊ ˈ eɪ s i . iː , - s i aɪ / poh- AY -see-e(y)e ), also called Gramineae ( / ɡ r ə ˈ m ɪ n i . iː , - n i aɪ / grə- MIN -ee-e(y)e ), is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses . It includes the cereal grasses, bamboos , the grasses of natural grassland and species cultivated in lawns and pasture . The latter are commonly referred to collectively as grass . With around 780 genera and around 12,000 species,

98-497: A sod -forming perennial grass used in agriculture is Thinopyrum intermedium . Grasses are used as raw material for a multitude of purposes, including construction and in the composition of building materials such as cob , for insulation, in the manufacture of paper and board such as oriented structural straw board . Grass fiber can be used for making paper , biofuel production, nonwoven fabrics, and as replacement for glass fibers used in reinforced plastics. Bamboo scaffolding

147-531: A botany Demonstrator and deputy to L. G. Le Monnier , professor of botany there in 1770. Le Monnier had succeeded Antoine-Laurent's uncle Antoine in 1759. Lectures by eminent botanists, including the Jusssieu dynasty were popular there, especially among pharmacists. His lecture on the classification of Ranunculaceae in 1773 to the Académie des Sciences led to his election as a member that year. In 1784 he

196-458: A definite group. The names he gave to his uncle's three major groupings were Acotyledon, Monocotyledon, and Dicotyledon. These were then divided into fifteen classes and one hundred families. The most important features of the Genera plantarum are the division into groups and the description and circumscription of the 100 families ( ordines naturales ). With the resumption of his scientific work at

245-414: A fringe of hairs (ciliate), and absent or lacking. Most grasses have ligules, and the shape, length, and appearance of the ligule margin provide consistent characters for separating genera and some species of grasses. In grass-like plants such as sedges ( Cyperaceae ) and rushes ( Juncaceae ), ligules are usually absent or poorly developed. In members of Asteraceae , a ligule is the elongated tongue of

294-590: A smaller part of the vegetation in almost every other terrestrial habitat. Grass-dominated biomes are called grasslands. If only large, contiguous areas of grasslands are counted, these biomes cover 31% of the planet's land. Grasslands include pampas , steppes , and prairies . Grasses provide food to many grazing mammals, as well as to many species of butterflies and moths . Many types of animals eat grass as their main source of food, and are called graminivores – these include cattle , sheep , horses , rabbits and many invertebrates , such as grasshoppers and

343-472: Is C4. Around 46 percent of grass species are C4 plants. The name Poaceae was given by John Hendley Barnhart in 1895, based on the tribe Poeae described in 1814 by Robert Brown , and the type genus Poa described in 1753 by Carl Linnaeus . The term is derived from the Ancient Greek πόα (póa, "fodder") . Grasses include some of the most versatile plant life-forms . They became widespread toward

392-473: Is a grass used as a culinary herb for its citrus-like flavor and scent. Many species of grass are grown as pasture for foraging or as fodder for prescribed livestock feeds, particularly in the case of cattle , horses , and sheep . Such grasses may be cut and stored for later feeding, especially for the winter, in the form of bales of hay or straw , or in silos as silage . Straw (and sometimes hay) may also be used as bedding for animals. An example of

441-566: Is able to withstand typhoon-force winds that would break steel scaffolding. Larger bamboos and Arundo donax have stout culms that can be used in a manner similar to timber, Arundo is used to make reeds for woodwind instruments , and bamboo is used for innumerable implements. Phragmites australis (common reed) is important for thatching and wall construction of homes in Africa. Grasses are used in water treatment systems, in wetland conservation and land reclamation , and used to lessen

490-524: Is also a strap-shaped extension of the corolla , such as that of a ray floret in plants in the daisy family Asteraceae . The ligule is part of the leaf that is found at the junction of the blade and sheath of the leaf. It may take several forms, but it is commonly some form of translucent membrane or a fringe of hairs. The membranous ligule can be very short 1–2 mm ( Kentucky bluegrass , Poa pratensis ) to very long 10–20 mm ( Johnson grass , Sorghum halepense ), it can also be smooth on

539-928: Is for piecing together historical landscapes and weather patterns, considering other factors such as genetic material amount might also affect pollen size. Despite these challenges, new techniques in Fourier-Transform Infrared Spectroscopy (FT-IR) and improved statistical methods are now helping to better identify these similar-looking pollen types. Grasses are the primary plants used in lawns, which themselves derive from grazed grasslands in Europe. They also provide an important means of erosion control (e.g., along roadsides), especially on sloping land. Grass lawns are an important covering of playing surfaces in many sports, including football (soccer) , American football , tennis , golf , cricket , softball and baseball . Juss. Jussieu

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588-602: Is linked to crop improvement, since meiotic recombination is an important component of plant breeding . Unlike in animals, the specification of both male and female plant germlines occurs late in development during flowering. The transition from the sporophyte phase to the gametophyte state is initiated by meiotic entry. Grasses are, in human terms, perhaps the most economically important plant family. Their economic importance stems from several areas, including food production, industry, and lawns . They have been grown as food for domesticated animals for up to 6,000 years and

637-463: Is the men that so appear who have made, and will continue to make, all the great generalisations of science." De Jussieu and his family have been commemorated by a number of images, including a bust and medallion by David d'Angers (Pierre-Jean David), upon his death. A statue of Jussieu, commissioned for 10,000  Fr by Jean-François Legendre-Héral in 1842, stands in the Galerie de Botanique of

686-773: The Albian stage of the Early Cretaceous approximately 113–100 million years ago, which were found to belong to primitive lineages within Poaceae, similar in position to the Anomochlooideae. These are currently the oldest known grass fossils. The relationships among the three subfamilies Bambusoideae, Oryzoideae and Pooideae in the BOP clade have been resolved: Bambusoideae and Pooideae are more closely related to each other than to Oryzoideae. This separation occurred within

735-508: The Americas ). Sugarcane is the major source of sugar production. Additional food uses of sugarcane include sprouted grain , shoots , and rhizomes , and in drink they include sugarcane juice and plant milk , as well as rum , beer , whisky , and vodka . Bamboo shoots are used in numerous Asian dishes and broths, and are available in supermarkets in various sliced forms, in both fresh, fermented and canned versions. Lemongrass

784-455: The Cenozoic contributed to the spread of grasses. Without large grazers, fire-cleared areas are quickly colonized by grasses, and with enough rain, tree seedlings. Trees eventually outcompete most grasses. Trampling grazers kill seedling trees but not grasses. Sexual reproduction and meiosis have been studied in rice , maize , wheat and barley . Meiosis research in these crop species

833-418: The ligule lies at the junction between sheath and blade, preventing water or insects from penetrating into the sheath. Flowers of Poaceae are characteristically arranged in spikelets , each having one or more florets. The spikelets are further grouped into panicles or spikes . The part of the spikelet that bears the florets is called the rachilla. A spikelet consists of two (or sometimes fewer) bracts at

882-658: The C4 plants are considered "warm-season" grasses. Although the C4 species are all in the PACMAD clade (see diagram below), it seems that various forms of C4 have arisen some twenty or more times, in various subfamilies or genera. In the Aristida genus for example, one species ( A. longifolia ) is C3 but the approximately 300 other species are C4. As another example, the whole tribe of Andropogoneae , which includes maize , sorghum , sugar cane , " Job's tears ", and bluestem grasses ,

931-626: The French Académie des Sciences (1773), elected foreign member of the Royal Swedish Academy of Sciences (1788). Jussieu's "natural" system of classification soon replaced the artificial sexual one of Linnaeus. The system of suprageneric nomenclature in botany is officially dated to 4 Aug 1789 with the publication of the Genera Plantarum (Gen. Pl.). The Genera plantarum was far-reaching in its impact; many of

980-646: The Jardin des Plantes. Another, by Jean-Baptiste Gustave Deloye is on the balustrade of the Natural History Museum, Vienna (facing Maria-Theresien-Platz ). The Jussieu botanical dynasty is commemorated in the neighbourhood of the Jardin des Plantes by the Place Jussieu, (Quartier Saint-Victor, 5th arrondissement ) Rue Jussieu, the Jussieu metro station and the Jussieu science campus of

1029-562: The Poaceae are used as building materials ( bamboo , thatch , and straw ); others can provide a source of biofuel , primarily via the conversion of maize to ethanol . Grasses have stems that are hollow except at the nodes and narrow alternate leaves borne in two ranks. The lower part of each leaf encloses the stem, forming a leaf-sheath. The leaf grows from the base of the blade, an adaptation allowing it to cope with frequent grazing. Grasslands such as savannah and prairie where grasses are dominant are estimated to constitute 40.5% of

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1078-612: The Poaceae is the fifth-largest plant family , following the Asteraceae , Orchidaceae , Fabaceae and Rubiaceae . The Poaceae are the most economically important plant family, providing staple foods from domesticated cereal crops such as maize , wheat , rice , oats , barley , and millet for people and as feed for meat-producing animals . They provide, through direct human consumption, just over one-half (51%) of all dietary energy; rice provides 20%, wheat supplies 20%, maize (corn) 5.5%, and other grains 6%. Some members of

1127-691: The University of Paris. The Jussieu family are also commemorated by street names in Marseilles and Lyon , their family home. The Jussieu Peninsula in South Australia is also named after Antoine Laurent Jussieu, as is an asteroid . Ligule#Poaceae and Cyperaceae A ligule (from Latin : ligula "strap", variant of lingula , from lingua "tongue") is a thin outgrowth at the junction of leaf and leafstalk of many grasses (family Poaceae) and sedges (family Cyperaceae) . A ligule

1176-437: The base, called glumes , followed by one or more florets. A floret consists of the flower surrounded by two bracts, one external—the lemma —and one internal—the palea . The flowers are usually hermaphroditic — maize being an important exception—and mainly anemophilous or wind-pollinated, although insects occasionally play a role. The perianth is reduced to two scales, called lodicules , that expand and contract to spread

1225-448: The caterpillars of many brown butterflies . Grasses are also eaten by omnivorous or even occasionally by primarily carnivorous animals. Grasses dominate certain biomes , especially temperate grasslands , because many species are adapted to grazing and fire. Grasses are unusual in that the meristem is near the bottom of the plant; hence, grasses can quickly recover from cropping at the top. The evolution of large grazing animals in

1274-437: The edge or very ragged. Some grasses do not have a ligule, for example barnyardgrass ( Echinochloa crus-galli ). A ligule can also be defined as a membrane-like tissue or row of delicate hairs typically found in grasses at the junction of the leaf sheath and blade. The ligule appears to be a continuation of the leaf sheath and encircles or clasps the stem as does the leaf sheath. The three basic types of ligules are: membranous,

1323-1033: The end of the Cretaceous period, and fossilized dinosaur dung ( coprolites ) have been found containing phytoliths of a variety that include grasses that are related to modern rice and bamboo . Grasses have adapted to conditions in lush rain forests , dry deserts , cold mountains and even intertidal habitats , and are currently the most widespread plant type; grass is a valuable source of food and energy for all sorts of wildlife. A cladogram shows subfamilies and approximate species numbers in brackets: Chloridoideae (1600) Danthonioideae (300) Micrairoideae (200) Arundinoideae (50) Panicoideae (3250) Aristidoideae (350) Oryzoideae (110) Bambusoideae – bamboos (1450) Pooideae (3850) Puelioideae (11) Pharoideae (13) Anomochlooideae (4) Before 2005, fossil findings indicated that grasses evolved around 55 million years ago. Finds of grass-like phytoliths in Cretaceous dinosaur coprolites from

1372-531: The entire plant kingdom, culminating in his epochal work, the Genera plantarum (1789). In preparing this work he had access to a large number of herbaria and botanical gardens . Although at first British and German botanists, firm adherents of the Linnaean system, were wary of what they considered radical ideas emanating from the French revolution, the work soon gained wide acceptance in scientific circles, and

1421-822: The erosional impact of urban storm water runoff. Pollen morphology, particularly in the Poaceae family, is key to figuring out their evolutionary relationships and how environments have changed over time . Grass pollen grains, however, often look the same, making it hard to use them for detailed climate or environmental reconstructions. Grass pollen has a single pore and can vary a lot in size, from about 20 to over 100 micrometers, and this size difference has been looked into for clues about past habitats, to tell apart domesticated grasses from wild ones, and to indicate various biological features like how they perform photosynthesis , their breeding systems, and genetic complexity. Yet, there's ongoing debate about how effective pollen size

1470-467: The full list of Poaceae genera . The grass family is one of the most widely distributed and abundant groups of plants on Earth . Grasses are found on every continent, including Antarctica . The Antarctic hair grass, Deschampsia antarctica is one of only two plant species native to the western Antarctic Peninsula . Grasses are the dominant vegetation in many habitats, including grassland , salt-marsh , reedswamp and steppes . They also occur as

1519-477: The grains of grasses such as wheat , rice, maize (corn) and barley have been the most important human food crops . Grasses are also used in the manufacture of thatch , paper , fuel , clothing , insulation , timber for fencing , furniture , scaffolding and construction materials, floor matting , sports turf and baskets . Of all crops grown, 70% are grasses. Agricultural grasses grown for their edible seeds are called cereals or grains (although

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1568-462: The land area of the Earth , excluding Greenland and Antarctica . Grasses are also an important part of the vegetation in many other habitats, including wetlands , forests and tundra . Though they are commonly called "grasses", groups such as the seagrasses , rushes and sedges fall outside this family. The rushes and sedges are related to the Poaceae, being members of the order Poales , but

1617-450: The latest Cretaceous ( Maastrichtian ) aged Lameta Formation of India have pushed this date back to 66 million years ago. In 2011, fossils from the same deposit were found to belong to the modern rice tribe Oryzeae , suggesting substantial diversification of major lineages by this time. In 2018, a study described grass microfossils extracted from the teeth of the hadrosauroid dinosaur Equijubus normani from northern China, dating to

1666-623: The latter term, when used agriculturally, refers to both cereals and similar seeds of other plant species, such as buckwheat and legumes ). Three cereals—rice, wheat, and maize (corn)—provide more than half of all calories consumed by humans. Cereals constitute the major source of carbohydrates for humans and perhaps the major source of protein; these include rice (in southern and eastern Asia ), maize (in Central and South America ), and wheat and barley (in Europe , northern Asia and

1715-457: The leaves are attached. Grass leaves are nearly always alternate and distichous (in one plane), and have parallel veins. Each leaf is differentiated into a lower sheath hugging the stem and a blade with entire (i.e., smooth) margins. The leaf blades of many grasses are hardened with silica phytoliths , which discourage grazing animals; some, such as sword grass , are sharp enough to cut human skin. A membranous appendage or fringe of hairs called

1764-465: The lemma and palea; these are generally interpreted to be modified sepals. The fruit of grasses is a caryopsis , in which the seed coat is fused to the fruit wall. A tiller is a leafy shoot other than the first shoot produced from the seed. Grass blades grow at the base of the blade and not from elongated stem tips. This low growth point evolved in response to grazing animals and allows grasses to be grazed or mown regularly without severe damage to

1813-549: The museum until 1826, when he was succeeded by his son Adrien-Henri . At the museum he published many papers in the museum's annals ( Annales du Museum d’histoire naturelle 1802–1813) and its succeeding Mémoires du Muséum d'histoire naturelle (1815–), as well as contributing articles to Frederic Cuvier 's Dictionnaire des sciences naturelles (1816-1830). He was also a member of the Masonic Lodge, Les Neuf Sœurs . Jussieu's system of plant classification , based on

1862-533: The museum, Jussieu's publications (some 60 memoirs) largely dealt with further elaborating the principles of the Genera plantarum and more detailed circumscription and description of the families he had named, work that was very much influenced by Joseph Gärtner . Although he worked on a second edition of Genera plantarum , all that was published was his Introductio , posthumously in 1837. Sources: Flourens (1840 , p. lvii); Pritzel (1872) ; Royal Society (1800–1900) Stafleu & Cowan (1979) Member of

1911-417: The number of stamens and pistils , though Jussieu did keep Linnaeus' binomial nomenclature . He extended his uncle's ideas about the value of the characteristics of plants. These characteristics were considered to be of unequal value, with some subordinate to others in a hierarchical system. As Jusssieu put it, plant characteristics should be pesés et non comptés (weighed, not counted), in assigning each to

1960-640: The plant. Three general classifications of growth habit present in grasses: bunch-type (also called caespitose), stoloniferous , and rhizomatous . The success of the grasses lies in part in their morphology and growth processes and in part in their physiological diversity. There are both C3 and C4 grasses, referring to the photosynthetic pathway for carbon fixation. The C4 grasses have a photosynthetic pathway, linked to specialized Kranz leaf anatomy , which allows for increased water use efficiency , rendering them better adapted to hot, arid environments. The C3 grasses are referred to as "cool-season" grasses, while

2009-468: The present-day plant families are still attributed to Jussieu. Morton's 1981 History of botanical science counts 76 of Jussieu's families conserved in the ICBN , versus just 11 for Linnaeus, for instance. Writing of the natural system, Sydney Howard Vines remarked: "The glory of this crowning achievement belongs to Jussieu: he was the capable man who appeared precisely at the psychological moment, and it

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2058-603: The relative value of their characteristics, served as the basis for natural systems of taxonomy. His system was first published in a paper on Ranunculaceae in 1773. The following year he developed the concept further in a paper on the arrangement of plants in the Jardin de Roi, based on the work of his uncle Bernard at the Trianon garden in Versaille. The work dealt primarily with suprafamilial ranks of classification. The following five years were devoted to applying his ideas to

2107-626: The relatively short time span of about 4 million years. According to Lester Charles King , the spread of grasses in the Late Cenozoic would have changed patterns of hillslope evolution favouring slopes that are convex upslope and concave downslope and lacking a free face were common. King argued that this was the result of more slowly acting surface wash caused by carpets of grass which in turn would have resulted in relatively more soil creep . There are about 12,000 grass species in about 771 genera that are classified into 12 subfamilies. See

2156-410: The seagrasses are members of the order Alismatales . However, all of them belong to the monocot group of plants. Grasses may be annual or perennial herbs , generally with the following characteristics (the image gallery can be used for reference): The stems of grasses, called culms , are usually cylindrical (more rarely flattened, but not 3-angled) and are hollow, plugged at the nodes , where

2205-423: Was actively promoted by eminent botanists including Robert Brown and A. P. de Candolle . In the Genera plantarum (1789), Jussieu adopted a methodology based on the use of multiple characters to define groups, an idea derived from naturalist Michel Adanson . This was a significant improvement over the "artificial" system of Linnaeus , whose most popular work classified plants into classes and orders based on

2254-403: Was also Director of the museum from 1794 to 1795, and again from 1798 to 1800. Jussieu immediately set about setting up a herbarium , a task greatly facilitated by the seizure of foreign collections by the revolutionary armies, and by the confiscation of the assets of the church and aristocracy. In 1808, Napoleon appointed him to the position of counsellor of the university. He remained at

2303-471: Was appointed to a Royal Commission by Louis XVI , as one of five commissionaires to investigate animal magnetism , publishing a dissenting opinion from the majority, suggesting further investigation was required. The publication of Jussieu's Genera plantarum in 1789 was rapidly followed by the outbreak of the French Revolution (1789–1799). Jussieu adhered to the revolutionary principles and

2352-518: Was appointed to a position in the municipal government of Paris, where he had the task of managing all the hospitals. With the overthrow of the monarchy, the Jardin du Roi was renamed the Jardin des plantes, and Jussieu was instrumental in reorganizing the Jardin as the Muséum national d'histoire naturelle in 1790, where he became a professor of botany, holding the chair in Botanique à la campagne. He

2401-517: Was born in Lyon , France, in 1748, as one of 10 children, to Christophle de Jussieu, an amateur botanist . His father's three younger brothers were also botanists. He went to Paris in 1765 to be with his uncle Bernard and to study medicine , graduating with a doctorate in 1770, with a thesis on animal and vegetable physiology. His uncle introduced him to the Jardin du Roi , where he was appointed as

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