There are about 380,000 known species of plants, of which the majority, some 260,000, produce seeds. They range in size from single cells to the tallest trees. Green plants provide a substantial proportion of the world's molecular oxygen; the sugars they create supply the energy for most of Earth's ecosystems and other organisms, including animals, either consume plants directly or rely on organisms which do so. (Full article...)
Banksia oblongifolia, commonly known as the fern-leaved, dwarf or rusty banksia, is a species in the plant genusBanksia. Found along the eastern coast of Australia from Wollongong, New South Wales in the south to Rockhampton, Queensland in the north, it generally grows in sandy soils in heath, open forest or swamp margins and wet areas. A many-stemmed shrub up to 3 m (9.8 ft) high, it has leathery serrated leaves and rusty-coloured new growth. The yellow flower spikes, known as inflorescences, most commonly appear in autumn and early winter. Up to 80 follicles, or seed pods, develop on the spikes after flowering. Banksia oblongifolia resprouts from its woody lignotuber after bushfires, and the seed pods open and release seed when burnt, the seed germinating and growing on burnt ground. Some plants grow between fires from seed shed spontaneously.
Spanish botanist Antonio José CavanillesdescribedB. oblongifolia in 1800, though it was known as Banksia aspleniifolia in New South Wales for many years. However, the latter name, originally coined by Richard Anthony Salisbury, proved invalid, and Banksia oblongifolia has been universally adopted as the correct scientific name since 1981. Two varieties were recognised in 1987, but these have not been generally accepted. A wide array of mammals, birds, and invertebrates visit the inflorescences. Though easily grown as a garden plant, it is not commonly seen in horticulture. (Full article...)
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Telopea oreades, commonly known as the Gippsland-, mountain- or Victorian waratah, is a large shrub or small tree in the family Proteaceae. Native to southeastern Australia, it is found in wet sclerophyll forest and rainforest on rich acidic soils high in organic matter. No subspecies are recognised, though a northern isolated population hybridises extensively with the Braidwood waratah (T. mongaensis). Reaching a height of up to 19 metres (62 feet), T. oreades grows with a single trunk and erect habit. It has dark green leaves with prominent veins that are 11–28 centimetres (4.3–11 in) long and 1.5–6 cm (0.6–2.4 in) wide. The red flower heads, known as inflorescences, appear in late spring. Each is composed of up to 60 individual flowers.
In the garden, T. oreades grows in soils with good drainage and ample moisture in part-shaded or sunny positions. Several commercially available cultivars that are hybrid forms with T. speciosissima have been developed, such as the 'Shady Lady' series. The timber is hard and has been used for making furniture and tool handles. (Full article...)
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Banksia verticillata, commonly known as granite banksia or Albany banksia, is a species of shrub or (rarely) tree of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 3 m (10 ft) in height. It can grow taller to 5 m (16 ft) in sheltered areas, and much smaller in more exposed areas. This species has elliptic green leaves and large, bright golden yellow inflorescences or flower spikes, appearing in summer and autumn. The New Holland honeyeater (Phylidonyris novaehollandiae) is the most prominent pollinator, although several other species of honeyeater, as well as bees, visit the flower spikes.
A declared vulnerable species, it occurs in two disjunct populations on granite outcrops along the south coast of Western Australia, with the main population near Albany and a smaller population near Walpole, and is threatened by dieback (Phytophthora cinnamomi) and aerial canker (Zythiostroma). B. verticillata is killed by bushfire and new plants regenerate from seed afterwards. Populations take over a decade to produce seed and fire intervals of greater than twenty years are needed to allow the canopy seed bank to accumulate. (Full article...)
Banksia sessilis, commonly known as parrot bush, is a species of shrub or tree in the plantgenusBanksia of the family Proteaceae. It had been known as Dryandra sessilis until 2007, when the genus Dryandra was sunk into Banksia. The Noongar peoples know the plant as budjan or butyak. Widespread throughout southwestWestern Australia, it is found on sandy soils over laterite or limestone, often as an understorey plant in open forest, woodland or shrubland. Encountered as a shrub or small tree up to 6 m (20 ft) in height, it has prickly dark green leaves and dome-shaped cream-yellow flowerheads. Flowering from winter through to late spring, it provides a key source of food—both the nectar and the insects it attracts—for honeyeaters in the cooler months, and species diversity is reduced in areas where there is little or no parrot bush occurring. Several species of honeyeater, some species of native bee, and the European honey bee seek out and consume the nectar, while the long-billed black cockatoo and Australian ringneck eat the seed. The life cycle of Banksia sessilis is adapted to regular bushfires. Killed by fire and regenerating by seed afterwards, each shrub generally produces many flowerheads and a massive amount of seed. It can recolonise disturbed areas, and may grow in thickets.
Banksia sessilis has a somewhat complicated taxonomic history. It was collected from King George Sound in 1801 and described by Robert Brown in 1810 as Dryandra floribunda, a name by which it was known for many years. However, Joseph Knight had published the name Josephia sessilis in 1809, which had precedence due to its earlier date, and the specific name was formalised in 1924. Four varieties are recognised. It is a prickly plant with little apparent horticultural potential; none of the varieties are commonly seen in cultivation. A profuse producer of nectar, B. sessilis is valuable to the beekeeping industry. (Full article...)
Johann George Adam Forster, also known as Georg Forster (German pronunciation:[ˈɡeːɔʁkˈfɔʁstɐ], 27 November 1754 – 10 January 1794), was a German geographer, naturalist, ethnologist, travel writer, journalist and revolutionary. At an early age, he accompanied his father, Johann Reinhold Forster, on several scientific expeditions, including James Cook's second voyage to the Pacific. His report of that journey, A Voyage Round the World, contributed significantly to the ethnology of the people of Polynesia and remains a respected work. As a result of the report, Forster, who was admitted to the Royal Society at the early age of twenty-two, came to be considered one of the founders of modern scientific travel literature.
After returning to continental Europe, Forster turned toward academia. He taught natural history at the Collegium Carolinum in the Ottoneum, Kassel (1778–84), and later at the Academy of Vilna (Vilnius University) (1784–87). In 1788, he became head librarian at the University of Mainz. Most of his scientific work during this time consisted of essays on botany and ethnology, but he also prefaced and translated many books about travel and exploration, including a German translation of Cook's diaries. (Full article...)
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Banksia caleyi, commonly known as Caley's banksia or red lantern banksia, is a species of woody shrub of the family Proteaceae native to Western Australia. It generally grows as a dense shrub up to 2 m (7 ft) tall, has serrated leaves and red, pendent (hanging) inflorescences which are generally hidden in the foliage. First described by Scottish naturalist Robert Brown in 1830, Banksia caleyi was named in honour of the English botanist George Caley. No subspecies are recognised. It is one of three or four related species with hanging inflorescences, which is an unusual feature within the genus.
Banksia aculeata, commonly known as prickly banksia, is a species of plant of the family Proteaceae native to the Stirling Range in the southwest of Western Australia. A shrub up to 2 m (7 ft) tall, it has dense foliage and leaves with very prickly serrated margins. Its unusual pinkish, pendent (hanging) flower spikes, known as inflorescences, are generally hidden in the foliage and appear during the early summer. Although it was collected by the naturalist James Drummond in the 1840s, Banksia aculeata was not formally described until 1981, by Alex George in his monograph of the genus.
A rare plant, Banksia aculeata is found in gravelly soils in elevated areas. Native to a habitat burnt by periodic bushfires, it is killed by fire and regenerates from seed afterwards. In contrast to other Western Australian banksias, it appears to have some resistance to the soil-borne water mouldPhytophthora cinnamomi. (Full article...)
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Telopea speciosissima flowerhead with florets opening from the edges towards the centre, Blue Mountains, Australia
The floral emblem for its home state of New South Wales, Telopea speciosissima has featured prominently in art, architecture, and advertising, particularly since Australian federation. Commercially grown in several countries as a cut flower, it is also cultivated in home gardens, requiring good drainage yet adequate moisture, but is vulnerable to various fungal diseases and pests. A number of cultivars with various shades of red, pink and even white flowers are available. Horticulturists have also developed hybrids with T. oreades and T. mongaensis which are more tolerant of cold, shade, and heavier soils. (Full article...)
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Banksia petiolaris is a rare species of flowering plant in the familyProteaceaenative to Western Australia, where it is found in sandy soils in the south coastal regions from Munglinup east to Israelite Bay. It was first described by Victorian state botanistFerdinand von Mueller in 1864, and no subspecies are recognised. B. petiolaris is one of several closely related species that will all grow as prostrate shrubs, with horizontal stems and thick, leathery upright leaves. Those of this species can be viable for up to 13 years—the longest-lived of any flowering plant recorded. It bears yellow cylindrical flower spikes, known as inflorescences, up to 16 cm (6+1⁄4 in) high in spring. As the spikes age, they turn grey and develop up to 20 woody seed pods, known as follicles, each.
Insects such as bees, wasps and even ants can pollinate the flowers. B. petiolaris is nonlignotuberous, meaning it regenerates by seed after bushfire. B. petiolaris adapts readily to cultivation, growing in well-drained sandy soils in sunny locations. It is suitable for rockeries and as a groundcover. (Full article...)
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Adenanthos cuneatus, also known as coastal jugflower, flame bush, bridle bush and sweat bush, is a shrub of the family Proteaceae, native to the south coast of Western Australia. The French naturalist Jacques Labillardière originally described it in 1805. Within the genus Adenanthos, it lies in the sectionAdenanthos and is most closely related to A. stictus. A. cuneatus has hybridized with four other species of Adenanthos. Growing to 2 m (6 ft 7 in) high and wide, it is erect to prostrate in habit, with wedge-shaped lobed leaves covered in fine silvery hair. The single red flowers are insignificant, and appear all year, though especially in late spring. The reddish new growth occurs over the summer.
It is sensitive to Phytophthora cinnamomidieback, hence requiring a sandy soil and good drainage to grow in cultivation, its natural habitat of sandy soils in heathland being an example. Its pollinators include bees, honey possum, silvereye and honeyeaters, particularly the western spinebill. A. cuneatus is grown in gardens in Australia and the western United States, and a dwarf and prostrate form are commercially available. (Full article...)
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Symphyotrichum lateriflorum (formerly Aster lateriflorus) is a species of flowering plant in the aster family (Asteraceae). Commonly known as calico aster, starved aster, and white woodland aster, it is native to eastern and central North America. It is a perennial and herbaceous plant that may reach heights up to 120 centimeters (4 feet) and widths up to 30 centimeters (1 foot).
The flowers of calico aster are small compared to most Symphyotrichum species. They have an average of 7–15 short white ray florets, which are rarely tinted pink or purple. The flower centers, composed of disk florets, begin as cream to yellow and often become pink, purple, or brown as they mature. There are roughly 8–16 disk florets, each with five lobes that strongly reflex (bend backwards) when open. The mostly hairless leaves have a characteristic hairy midrib on their back faces, and branching is usually horizontal or in what can appear to be a zigzag pattern. Flower heads grow along one side of the branches and sometimes in clusters at the ends. (Full article...)
Banksia brownii, commonly known as feather-leaved banksia or Brown's banksia, is a species of shrub that grows in southwestWestern Australia. A plant with fine feathery leaves and large red-brown flower spikes, it usually grows as an upright bush around two metres (6.6 ft) high, but can also occur as a small tree or a low spreading shrub. First collected in 1829 and published the following year, it is placed in Banksiasubgenus Banksia, section Oncostylis, series Spicigerae. There are two genetically distinct forms.
Banksia brownii occurs naturally only in two population clusters between Albany and the Stirling Range in southwest Western Australia. In the Stirling Range it occurs among heath on rocky mountain slopes; further south it occurs among jarrahwoodland in shallow nutrient-poor sand. It has been evaluated as critically endangered by the International Union for Conservation of Nature (IUCN); all major populations are threatened by Phytophthora cinnamomi dieback, a disease to which the species is highly susceptible. Other threats include loss of habitat, commercial exploitation and changes to the fire regime. Highly valued by Australia's horticultural and cut flower industries, B. brownii is widely cultivated in areas not exposed to dieback. It prefers a sheltered position in soil with good drainage, and must be provided with some moisture over summer. (Full article...)
A cabbage generally weighs between 500 and 1,000 grams (1 and 2 lb). Smooth-leafed, firm-headed green cabbages are the most common, with smooth-leafed purple cabbages and crinkle-leafed savoy cabbages of both colours being rarer. Under conditions of long sunny days, such as those found at high northern latitudes in summer, cabbages can grow quite large. , the heaviest cabbage was 62.71 kilograms (138 lb 4 oz). Cabbage heads are generally picked during the first year of the plant's life cycle, but plants intended for seed are allowed to grow a second year and must be kept separate from other cole crops to prevent cross-pollination. Cabbage is prone to several nutrient deficiencies, as well as to multiple pests, and bacterial and fungal diseases. (Full article...)
Banksia aemula, commonly known as the wallum banksia, is a shrub of the family Proteaceae. Found from Bundaberg south to Sydney on the Australian east coast, it is encountered as a shrub or a tree to 8 m (26 ft) in coastal heath on deep sandy soil, known as Wallum. It has wrinkled orange bark and shiny green serrated leaves, with green-yellow flower spikes, known as inflorescences, appearing in autumn. The flower spikes turn grey as they age and large grey follicles appear. Banksia aemula resprouts from its woody base, known as a lignotuber, after bushfires.
First described by the botanist Robert Brown in the early 19th century, it derives its specific name "similar" from its resemblance to the closely related B. serrata. No varieties are recognised. It was known for many years in New South Wales as B. serratifolia, contrasting with the use of B. aemula elsewhere. However, the former name, originally coined by Richard Anthony Salisbury, proved invalid, and Banksia aemula has been universally adopted as the correct scientific name since 1981. A wide array of mammals, birds, and invertebrates visit the inflorescences and are instrumental in pollination; honeyeaters are particularly prominent visitors. Grown as a garden plant, it is less commonly seen in horticulture than its close relative B. serrata. (Full article...)
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McClintock in her laboratory, 1947
Barbara McClintock (June 16, 1902 – September 2, 1992) was an American scientist and cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine. McClintock received her PhD in botany from Cornell University in 1927. There she started her career as the leader of the development of maize cytogenetics, the focus of her research for the rest of her life. From the late 1920s, McClintock studied chromosomes and how they change during reproduction in maize. She developed the technique for visualizing maize chromosomes and used microscopic analysis to demonstrate many fundamental genetic ideas. One of those ideas was the notion of genetic recombination by crossing-over during meiosis—a mechanism by which chromosomes exchange information. She produced the first genetic map for maize, linking regions of the chromosome to physical traits. She demonstrated the role of the telomere and centromere, regions of the chromosome that are important in the conservation of genetic information. She was recognized as among the best in the field, awarded prestigious fellowships, and elected a member of the National Academy of Sciences in 1944.
During the 1940s and 1950s, McClintock discovered transposons and used it to demonstrate that genes are responsible for turning physical characteristics on and off. She developed theories to explain the suppression and expression of genetic information from one generation of maize plants to the next. Due to skepticism of her research and its implications, she stopped publishing her data in 1953. (Full article...)
This is a list of crop plants pollinated by bees along with how much crop yield is improved by bee pollination. Most of them are pollinated in whole or part by honey bees and by the crop's natural pollinators such as bumblebees, orchard bees, squash bees, and solitary bees. Where the same plants have non-bee pollinators such as birds or other insects like flies, these are also indicated.
Pollination by insects is called entomophily. Entomophily is a form of plant pollination whereby pollen is distributed by insects, particularly bees, Lepidoptera (butterflies and moths), flies and beetles. Honey bees pollinate many plant species that are not native to their natural habitat but are often inefficient pollinators of such plants; if they are visiting ten different species of flower, only a tenth of the pollen they carry may be the right species. Other bees tend to favor one species at a time, therefore do most of the actual pollination. (Full article...)
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Jean H. Langenheim (née Harmon; September 5, 1925 – March 28, 2021) was an American plant ecologist and ethnobotanist, highly respected as an eminent scholar and a pioneer for women in the field. She has done field research in arctic, tropical, and alpine environments across five continents, with interdisciplinary research that spans across the fields of chemistry, geology, and botany. Her early research helped determine the plant origins of amber and led to her career-long work investigating the chemical ecology of resin-producing trees, including the role of plant resins for plant defense and the evolution of several resin-producing trees in the tropics. She wrote what is regarded as the authoritative reference on the topic: Plant Resins: Chemistry, Evolution, Ecology, and Ethnobotany, published in 2003.
Langenheim earned a PhD in botany with a minor in geology in 1953 from the University of Minnesota. She was the first female faculty member in the natural sciences and first woman to be promoted to full professor at the University of California, Santa Cruz. She was the first woman to serve as president for the Association for Tropical Biology, second woman to serve as president of the Ecological Society of America (ESA) and Society for Economic Botany, founded and served as the first president for the International Society of Chemical Ecology, and was a fellow of the American Association for the Advancement of Science and the California Academy of Sciences. During her time as ESA president, she initiated a project to document women's experiences and contributions to the field of ecology and conducted a follow-up project in 1996. Her research was summarized in two publications, and resulted in a large historical collection and a continued effort by ESA to document women's contributions to the field. (Full article...)
Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particular have long propagated using the movements of humans and other animals in a symbiotic relationship that is the means for seed dispersal for the one group and nutrition for the other; humans and many other animals have become dependent on fruits as a source of food. Consequently, fruits account for a substantial fraction of the world's agricultural output, and some (such as the apple and the pomegranate) have acquired extensive cultural and symbolic meanings. (Full article...)
Bernard de Jussieu was born in Lyon. He took a medical degree at Montpellier and began practice in 1720, but finding the work uncongenial he gladly accepted his brother's invitation to Paris in 1722, when he succeeded Sebastien Vaillant (1669–1722) as sub-demonstrator of plants in the Jardin des Plantes. In 1725 he brought out a new edition of Joseph Pitton de Tournefort's Histoire des plantes qui naissent aux environs de Paris, 2 vols., which was afterwards translated into English by John Martyn, the original work being incomplete. In the same year he was admitted into the French Academy of Sciences, and communicated several papers to that body. (Full article...)
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An ethylene signal transduction pathway. Ethylene permeates the cell membrane and binds to a receptor on the endoplasmic reticulum. The receptor releases the repressed EIN2. This then activates a signal transduction pathway which activates regulatory genes that eventually trigger an ethylene response. The activated DNA is transcribed into mRNA which is then translated into a functional enzyme that is used for ethylene biosynthesis. Ethylene (CH 2=CH 2) is an unsaturatedhydrocarbon gas (alkene) acting as a naturally occurring plant hormone. It is the simplest alkene gas and is the first gas known to act as hormone. It acts at trace levels throughout the life of the plant by stimulating or regulating the ripening of fruit, the opening of flowers, the abscission (or shedding) of leaves and, in aquatic and semi-aquatic species, promoting the 'escape' from submergence by means of rapid elongation of stems or leaves. This escape response is particularly important in rice farming. Commercial fruit-ripening rooms use "catalytic generators" to make ethylene gas from a liquid supply of ethanol. Typically, a gassing level of 500 to 2,000 ppm is used, for 24 to 48 hours. Care must be taken to control carbon dioxide levels in ripening rooms when gassing, as high temperature ripening (20 °C; 68 °F) has been seen to produce CO2 levels of 10% in 24 hours. (Full article...)
Chamaenerion is a genus of flowering plants in the familyOnagraceae (the evening primrose or willowherb family). It has sometimes been included in the genus Epilobium. Members of the genus may be called willowherbs (along with Epilobium), or fireweeds, based on a common name used for C. angustifolium. They are upright herbaceousperennials, growing from a woody base or from rhizomes, with racemes of usually purple to pink flowers. All species are found in the northern hemisphere. Most occur in moist habitats; C. angustifolium is the exception, favouring disturbed ground. (Full article...)
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A tropical plant community on Diego Garcia Plant ecology is a subdiscipline of ecology that studies the distribution and abundance of plants, the effects of environmental factors upon the abundance of plants, and the interactions among plants and between plants and other organisms. Examples of these are the distribution of temperate deciduous forests in North America, the effects of drought or flooding upon plant survival, and competition among desert plants for water, or effects of herds of grazing animals upon the composition of grasslands.
A global overview of the Earth's major vegetation types is provided by O.W. Archibold. He recognizes 11 major vegetation types: tropical forests, tropical savannas, arid regions (deserts), Mediterranean ecosystems, temperate forest ecosystems, temperate grasslands, coniferous forests, tundra (both polar and high mountain), terrestrial wetlands, freshwater ecosystems and coastal/marine systems. This breadth of topics shows the complexity of plant ecology, since it includes plants from floating single-celled algae up to large canopy forming trees. (Full article...)
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Redcurrants, a type of berry derived from a simple (one-locule) inferior ovary In botany, a berry is a fleshy fruit without a stone (pit) produced from a single flower containing one ovary. Berries so defined include grapes, currants, and tomatoes, as well as cucumbers, eggplants (aubergines), persimmons and bananas, but exclude certain fruits that meet the culinary definition of berries, such as strawberries and raspberries. The berry is the most common type of fleshy fruit in which the entire outer layer of the ovary wall ripens into a potentially edible "pericarp". Berries may be formed from one or more carpels from the same flower (i.e. from a simple or a compound ovary). The seeds are usually embedded in the fleshy interior of the ovary, but there are some non-fleshy exceptions, such as Capsicum species, with air rather than pulp around their seeds.
Photorespiration (also known as the oxidative photosynthetic carbon cycle or C2 cycle) refers to a process in plant metabolism where the enzymeRuBisCO oxygenates RuBP, wasting some of the energy produced by photosynthesis. The desired reaction is the addition of carbon dioxide to RuBP (carboxylation), a key step in the Calvin–Benson cycle, but approximately 25% of reactions by RuBisCO instead add oxygen to RuBP (oxygenation), creating a product that cannot be used within the Calvin–Benson cycle. This process lowers the efficiency of photosynthesis, potentially lowering photosynthetic output by 25% in C3 plants. Photorespiration involves a complex network of enzyme reactions that exchange metabolites between chloroplasts, leaf peroxisomes and mitochondria.
The oxygenation reaction of RuBisCO is a wasteful process because 3-phosphoglycerate is created at a lower rate and higher metabolic cost compared with RuBP carboxylase activity. While photorespiratory carbon cycling results in the formation of G3P eventually, around 25% of carbon fixed by photorespiration is re-released as CO2 and nitrogen, as ammonia. Ammonia must then be detoxified at a substantial cost to the cell. Photorespiration also incurs a direct cost of one ATP and one NAD(P)H. (Full article...)
Agroforestry can be practiced for economic, environmental, and social benefits, and can be part of sustainable agriculture. Apart from production, benefits from agroforestry include improved farm productivity, healthier environments, reduction of risk for farmers, beauty and aesthetics, increased farm profits, reduced soil erosion, creating wildlife habitat, less pollution, managing animal waste, increased biodiversity, improved soil structure, and carbon sequestration. (Full article...)
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Cotyledon from a Judas-tree (Cercis siliquastrum, a dicot) seedling A cotyledon (/ˌkɒtɪˈliːdən/; from Latincotyledon; from κοτυληδών (kotulēdṓn) "a cavity, small cup, any cup-shaped hollow", gen. κοτυληδόνος (kotulēdónos), from κοτύλη (kotýlē) 'cup, bowl') is a "seed leaf" - a significant part of the embryo within the seed of a plant, and is formally defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." Botanists use the number of cotyledons present as one characteristic to classify the flowering plants (angiosperms): species with one cotyledon are called monocotyledonous ("monocots"); plants with two embryonic leaves are termed dicotyledonous ("dicots").
In the case of dicot seedlings whose cotyledons are photosynthetic, the cotyledons are functionally similar to leaves. However, true leaves and cotyledons are developmentally distinct. Cotyledons form during embryogenesis, along with the root and shoot meristems, and are therefore present in the seed prior to germination. True leaves, however, form post-embryonically (i.e. after germination) from the shoot apical meristem, which generates subsequent aerial portions of the plant. (Full article...)
White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all harvested from one of two major varieties grown today, C. sinensis var. sinensis and C. s. var. assamica, but are processed differently to attain varying levels of oxidation with black tea being the most oxidized and white being the least. Kukicha (twig tea) is also harvested from C. sinensis, but uses twigs and stems rather than leaves. (Full article...)
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Lack of the plant hormone auxin can cause abnormal growth (right)
Plant hormones (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, including embryogenesis, the regulation of organ size, pathogen defense, stress tolerance and reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book.
The Yecoro wheat (right) cultivar is sensitive to salinity, plants resulting from a hybrid cross with cultivar W4910 (left) show greater tolerance to high salinity
Plant breeding is the science of changing the traits of plants in order to produce desired characteristics. It has been used to improve the quality of nutrition in products for humans and animals. The goals of plant breeding are to produce crop varieties that boast unique and superior traits for a variety of applications. The most frequently addressed agricultural traits are those related to biotic and abiotic stress tolerance, grain or biomass yield, end-use quality characteristics such as taste or the concentrations of specific biological molecules (proteins, sugars, lipids, vitamins, fibers) and ease of processing (harvesting, milling, baking, malting, blending, etc.).
Plant breeding can be performed through many different techniques ranging from simply selecting plants with desirable characteristics for propagation, to methods that make use of knowledge of genetics and chromosomes, to more complex molecular techniques. Genes in a plant are what determine what type of qualitative or quantitative traits it will have. Plant breeders strive to create a specific outcome of plants and potentially new plant varieties, and in the course of doing so, narrow down the genetic diversity of that variety to a specific few biotypes. (Full article...)
Immature cones of a Colorado Blue Spruce (Picea pungens), a species of spruce native to western North America. It is a medium-sized evergreen tree growing to 25 to 30 metres (82 to 98 ft) tall, exceptionally to 46 m (151 ft) tall, and with a trunk diameter of up to 1.5 m (4.9 ft). The cones are slender and cylindrical, 6–11 centimetres (2.4–4.3 in) long, and are reddish to violet in color, maturing to pale brown 5–7 months after pollination. The Blue Spruce is the state tree of Utah and Colorado.
In 2022, barley was fourth among grains in quantity produced, 155 million tonnes, behind maize, wheat, and rice. Globally, 70% of barley production is used as animal feed, while 30% is used as a source of fermentable material for beer, or further distilled into whisky, and as a component of various foods. It is used in soups and stews and in barley bread of various cultures. Barley grains are commonly made into malt using a traditional and ancient method of preparation. In English folklore, John Barleycorn personifies the grain and the alcoholic beverages made from it. English pub names such as The Barley Mow allude to barley's role in the production of beer. (Full article...)
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Orange—whole, halved, and peeled segment An orange, also called sweet orange to distinguish it from the bitter orange (Citrus × aurantium), is the fruit of a tree in the familyRutaceae. Botanically, this is the hybrid Citrus × sinensis, between the pomelo (Citrus maxima) and the mandarin orange (Citrus reticulata). The chloroplastgenome, and therefore the maternal line, is that of pomelo. The sweet orange has had its full genome sequenced.
The orange originated in a region encompassing Southern China, Northeast India, and Myanmar; the earliest mention of the sweet orange was in Chinese literature in 314 BC. Orange trees are widely grown for their sweet fruit. The fruit of the orange tree can be eaten fresh, or processed for its juice or fragrant peel. In 2022, 76 million tonnes of oranges were grown worldwide, with Brazil producing 22% of the total, followed by India and China. (Full article...)
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Spear Thistle The flora of Scotland is an assemblage of native plant species including over 1,600 vascular plants, more than 1,500 lichens and nearly 1,000 bryophytes. The total number of vascular species is low by world standards but lichens and bryophytes are abundant and the latter form a population of global importance. Various populations of rare fern exist, although the impact of 19th-century collectors threatened the existence of several species. The flora is generally typical of the north-west European part of the Palearctic realm and prominent features of the Scottish flora include borealCaledonian forest (much reduced from its natural extent), heather moorland and coastal machair. In addition to the native species of vascular plants there are numerous non-native introductions, now believed to make up some 43% of the species in the country.
There are a variety of important trees species and specimens; a Grand Fir in Argyll is the tallest tree in the United Kingdom and the Fortingall Yew may be the oldest tree in Europe. The Arran Whitebeams, Shetland Mouse-ear and Scottish Primrose are endemic flowering plants and there are a variety of endemic mosses and lichens. Conservation of the natural environment is well developed and various organisations play an important role in the stewardship of the country's flora. Numerous references to the country's flora appear in folklore, song and poetry. (Full article...)
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Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné, was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern taxonomy". Many of his writings were in Latin; his name is rendered in Latin as Carolus Linnæus and, after his 1761 ennoblement, as Carolus a Linné.
Linnaeus was the son of a curate and he was born in Råshult, the countryside of Småland, in southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his Systema Naturae in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In the 1750s and 1760s, he continued to collect and classify animals, plants, and minerals, while publishing several volumes. By the time of his death in 1778, he was one of the most acclaimed scientists in Europe. (Full article...)
A plant epithet is a name used to label a person or group, by association with some perceived quality of a plant. Vegetableepithets may be pejorative, such as turnip, readily giving offence, or positive, such as rose or other flowers implying beauty. Tree and flower forenames such as Hazel, Holly, Jasmine and Rose are commonly given to girls. Tree surnames such as Oakes (Oak) and Nash (Ash) are toponymic, given to a person in the Middle Ages who lived in a place near a conspicuous tree. A few plant surnames such as Pease and Onions are metonymic, for sellers of peas and onions respectively. Finally, plant surnames are sometimes emblematic, as in the name Rose, used as a family emblem. (Full article...)
The taxonomy of the plant family Liliaceae has had a complex history since its first description in the mid-eighteenth century. Originally, the Liliaceae were defined as having a "calix" (perianth) of six equal-coloured parts, six stamens, a single style, and a superior, three-chambered (trilocular) ovary turning into a capsule fruit at maturity. The taxonomic circumscription of the family Liliaceae progressively expanded until it became the largest plant family and also extremely diverse, being somewhat arbitrarily defined as all species of plants with six tepals and a superior ovary. It eventually came to encompass about 300 genera and 4,500 species, and was thus a "catch-all" and hence paraphyletic. Only since the more modern taxonomic systems developed by the Angiosperm Phylogeny Group (APG) and based on phylogenetic principles, has it been possible to identify the many separate taxonomic groupings within the original family and redistribute them, leaving a relatively small core as the modern family Liliaceae, with fifteen genera and 600 species.
Cabbage tree on farmland, South Island, New Zealand
Cordyline australis, commonly known as the cabbage tree, or by its Māori name of tī or tī kōuka, is a widely branched monocot tree endemic to New Zealand.
It grows up to 20 metres (66 feet) tall with a stout trunk and sword-like leaves, which are clustered at the tips of the branches and can be up to 1 metre (3 feet 3 inches) long. With its tall, straight trunk and dense, rounded heads, it is a characteristic feature of the New Zealand landscape. Its fruit is a favourite food source for the kererū and other native birds. It is common over a wide latitudinal range from the far north of the North Island at 34° 25′S to the south of the South Island at 46° 30′S. Absent from much of Fiordland, it was probably introduced by Māori to the Chatham Islands at 44° 00′S and to Stewart Island / Rakiura at 46° 50′S. It grows in a broad range of habitats, including forest margins, river banks and open places, and is abundant near swamps. The largest known tree with a single trunk is growing at Pākawau, Golden Bay / Mohua. It is estimated to be 400 or 500 years old, and stands 17 metres (56 feet) tall with a circumference of 9 metres (30 feet) at the base. (Full article...)
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Betula pendula, commonly known as silver birch, warty birch, European white birch, or East Asian white birch, is a species of tree in the familyBetulaceae, native to Europe and parts of Asia, though in southern Europe, it is only found at higher altitudes. Its range extends into Siberia, China, and southwest Asia in the mountains of northern Turkey, the Caucasus, and northern Iran. It has been introduced into North America, where it is known as the European white birch or weeping birch and is considered invasive in some states in the United States and parts of Canada. The tree can also be found in more temperate regions of Australia.
The silver birch is a medium-sized deciduous tree that owes its common name to the white peeling bark on the trunk. The twigs are slender and often pendulous and the leaves are roughly triangular with doubly serrate margins and turn yellow and brown in autumn before they fall. The flowers are catkins and the light, winged seeds get widely scattered by the wind. The silver birch is a hardy tree, a pioneer species, and one of the first trees to appear on bare or fire-swept land. Many species of birds and animals are found in birch woodland, the tree supports a wide range of insects and the light shade it casts allows shrubby and other plants to grow beneath its canopy. It is planted decoratively in parks and gardens and is used for forest products such as joinery timber, firewood, tanning, racecourse jumps, and brooms. Various parts of the tree are used in traditional medicine and the bark contains triterpenes, which have been shown to have medicinal properties. (Full article...)
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Artist's reconstruction of Archaeamphora longicervia after Li (2005)
The species was originally described as a pitcher plant with close affinities to extant members of the familySarraceniaceae. This would make it the earliest known carnivorous plant and the only known fossil record of Sarraceniaceae, or the New World pitcher plant family. Archaeamphora is also one of the three oldest known genera of angiosperms (flowering plants). Li (2005) wrote that "the existence of a so highly derived Angiosperm in the Early Cretaceous suggests that Angiosperms should have originated much earlier, maybe back to 280 mya as the molecular clock studies suggested". (Full article...)
Despite its prominence in the industry, the grape is a relatively new variety, the product of a chance crossing between Cabernet Franc and Sauvignon blanc during the 17th century in southwestern France. Its popularity is often attributed to its ease of cultivation—the grapes have thick skins and the vines are hardy and naturally low yielding, budding late to avoid frost and resistant to viticultural hazards such as rot and insects—and to its consistent presentation of structure and flavours which express the typical character ("typicity") of the variety. Familiarity has helped sell Cabernet Sauvignon wines to consumers, even from unfamiliar wine regions. Its widespread popularity has also contributed to criticism of the grape as a "colonizer" that takes over wine regions at the expense of indigenous grape varieties. (Full article...)
Wild species of cherry tree are widely distributed, mainly in the Northern Hemisphere. They are common in East Asia, especially in Japan, where they have been cultivated, producing many varieties. (Full article...)
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Norman C. Deno (February 15, 1921 – September 22, 2017) was an American chemist and plant scientist. He was a professor of chemistry at Penn State University and is known as one of the foremost researchers in seed germination theory. He researched the biochemical reactions that underlie the germination of all seeds, performing germination research on plant species from 150 families, 800 genera, and 2500 species over the course of his career. Deno authored 150 papers in chemistry and 20 papers in horticulture, and self-published a number of books that combined his scientific results.
A Chicagoan, Deno had an interest in plants from a young age, but obtained a post-doctoral degree in chemistry as a more lucrative career opportunity. His chemistry professor position at Penn State University resulted in a discovery by his lab on coal refinement for oil refineries that earned him a large amount of wealth from grants. He later reduced his focus on chemistry to pursue his interests in horticulture. Determining the germination requirements for plants had Deno create the "baggie and paper towel" method for mimicking laboratory growth settings and his general low tech methodologies would end up being dubbed "The Deno Method". His approach to seed germination would result in multiple interviews in newspapers and for books, along with seed companies coming to him specifically for specific cultivar research. He went on to publish multiple books covering seed germination theory and he received awards from the North American Rock Garden Society for his work. (Full article...)
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The lily family, Liliaceae, consists of about 15 genera and 610 species of flowering plants within the orderLiliales. They are monocotyledonous, perennial, herbaceous, often bulbousgeophytes. Plants in this family have evolved with a fair amount of morphological diversity despite genetic similarity. Common characteristics include large flowers with parts arranged in threes: with six colored or patterned petaloidtepals (undifferentiated petals and sepals) arranged in two whorls, six stamens and a superior ovary. The leaves are linear in shape, with their veins usually arranged parallel to the edges, single and arranged alternating on the stem, or in a rosette at the base. Most species are grown from bulbs, although some have rhizomes. First described in 1789, the lily family became a paraphyletic "catch-all" (wastebasket) group of lilioid monocots that did not fit into other families and included a great number of genera now included in other families and in some cases in other orders. Consequently, many sources and descriptions labelled "Liliaceae" deal with the broader sense of the family.
The family evolved approximately 68 million years ago during the Late Cretaceous to Early Paleogene epochs. Liliaceae are widely distributed, mainly in temperate regions of the Northern Hemisphere and the flowers are insect pollinated. Many Liliaceae are important ornamental plants, widely grown for their attractive flowers and involved in a major floriculture of cut flowers and dry bulbs. Some species are poisonous if eaten and can have adverse health effects in humans and household pets. (Full article...)
Wheat is grown on a larger area of land than any other food crop (220.7 million hectares or 545 million acres in 2021). World trade in wheat is greater than for all other crops combined. In 2021, world wheat production was 771 million tonnes (850 million short tons), making it the second most-produced cereal after maize (known as corn in North America and Australia; wheat is often called corn in countries including Britain). Since 1960, world production of wheat and other grain crops has tripled and is expected to grow further through the middle of the 21st century. Global demand for wheat is increasing because of the usefulness of gluten to the food industry. (Full article...)
The leaflets of the plant are obovate-oblong and equal-sided, and of a silky texture. The fruits (legumes) are typically 1 to 2 in (25 to 51 mm) long and contain six or seven brownish seeds. The species typically grows in areas where the soils are relatively deep, especially in semi-arid and wadi areas, and on terraces and slight inclines and hills. (Full article...)
... that New York City's Bartow–Pell Mansion became a museum after its operator was restricted from importing and exporting plants?
... that while most lichens that grow on plants live on the surface, the sole species in Amazonotrema grows partially among the cells of the tree bark on which it lives?
... that Marie Catharine Neal, an expert on Hawaiian plants, authored the acclaimed book In Gardens of Hawaii in 1948, which described more than 2,000 species with detailed scientific information and illustrations?
... that the woodland garden, "colourfully planted with exotic shrubs and herbaceous plants, dominated English horticulture from 1910 to 1960"?
The following are images from various plant-related articles on Wikipedia.
Image 1Thale cress, Arabidopsis thaliana, the first plant to have its genome sequenced, remains the most important model organism. (from Botany)
Image 2A late Siluriansporangium, artificially colored. Green: A spore tetrad. Blue: A spore bearing a trilete mark – the Y-shaped scar. The spores are about 30–35 μm across. (from Evolutionary history of plants)
Image 5The food we eat comes directly or indirectly from plants such as rice. (from Botany)
Image 6Five of the key areas of study within plant physiology (from Botany)
Image 7The trunk of early tree fern Psaronius, showing internal structure. The top of the plant would have been to the left of the image (from Evolutionary history of plants)
Image 8Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 9A banded tube from the Late Silurian/Early Devonian. The bands are difficult to see on this specimen, as an opaque carbonaceous coating conceals much of the tube. Bands are just visible in places on the left half of the image. Scale bar: 20 μm (from Evolutionary history of plants)
Image 14Structure of Azadirachtin, a terpenoid produced by the Neem plant, which helps ward off microbes and insects. Many secondary metabolites have complex structures (from Evolutionary history of plants)
Image 161 An oat coleoptile with the sun overhead. Auxin (pink) is evenly distributed in its tip. 2 With the sun at an angle and only shining on one side of the shoot, auxin moves to the opposite side and stimulates cell elongation there. 3 and 4 Extra growth on that side causes the shoot to bend towards the sun. (from Botany)
Image 28The fruit of Myristica fragrans, a species native to Indonesia, is the source of two valuable spices, the red aril (mace) enclosing the dark brown nutmeg. (from Botany)
Image 31The evolution of syncarps. a: sporangia borne at tips of leaf b: Leaf curls up to protect sporangia c: leaf curls to form enclosed roll d: grouping of three rolls into a syncarp (from Evolutionary history of plants)
Image 32The branching pattern of megaphyll veins may indicate their origin as webbed, dichotomising branches. (from Evolutionary history of plants)
Image 33This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
Image 34The Devonian marks the beginning of extensive land colonization by plants, which – through their effects on erosion and sedimentation – brought about significant climatic change. (from Evolutionary history of plants)
Image 35Structure of a plant cell (from Plant cell)
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