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...)
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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Alloxylon pinnatum, known as Dorrigo waratah, is a tree of the family Proteaceae found in warm-temperate rainforest of south-east Queensland and northern New South Wales in eastern Australia. It has shiny green leaves that are either pinnate (lobed) and up to 30cm (12in) long, or lanceolate (spear-shaped) and up to 15cm (5.9in) long. The prominent pinkish-red flower heads, known as inflorescences, appear in spring and summer; these are made up of 50 to 140 individual flowers arranged in corymb or raceme. These are followed by rectangular woody seed pods, which bear two rows of winged seeds.
Known for many years as Oreocallis pinnata, it was transferred to the new genus Alloxylon by Peter Weston and Mike Crisp in 1991. This genus contains the four species previously classified in Oreocallis that are found in Australasia. Its terminal globular flowers indicate that the species is pollinated by birds. Classified as near threatened under the Queensland Nature Conservation Act 1992, the Dorrigo waratah has proven difficult to keep alive in cultivation. (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...)
Its aromatic, "labrusca" flavor is similar to that of Concord, but mellowed by the mild, sweet taste from Thompson Seedless. Thomcord grows well in hot, dry climates, ripens between late July and mid-August, and tolerates powdery mildew. It is a productive variety, yielding an average of 15.1kg (33lb) of grapes per vine, but has produced as much as 30 to 32kg (66 to 71lb) per vine in grower trials. The berries weigh between 2.72 and 3.38g (0.096 and 0.119oz) and have a medium-thick, blue-black skin that adheres to the fruit, unlike Concord, which has a thick skin that can slip off the pulp easily. The aborted seeds in the fruit body are relatively small, but larger than those in Thompson Seedless. (Full article...)
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Wild form of Xerochrysum bracteatum
Xerochrysum bracteatum, commonly known as the golden everlasting or strawflower, is a flowering plant in the family Asteraceae native to Australia. Described by Étienne Pierre Ventenat in 1803, it was known as Helichrysum bracteatum for many years before being transferred to a new genus Xerochrysum in 1990. It is an annual up to 1m (3.3ft) tall with green or grey leafy foliage. Golden yellow or white flower heads are produced from spring to autumn; their distinctive feature is the papery bracts that resemble petals. The species is widespread, growing in a variety of habitats across the country, from rainforest margins to deserts and subalpine areas. The golden everlasting serves as food for various larvae of lepidopterans (butterflies and moths), and adult butterflies, hoverflies, native bees, small beetles, and grasshoppers visit the flower heads.
The golden everlasting has proven very adaptable to cultivation. It was propagated and developed in Germany in the 1850s, and annual cultivars in a host of colour forms from white to bronze to purple flowers became available. Many of these are still sold in mixed seed packs. In Australia, many cultivars are perennial shrubs, which have become popular garden plants. Sturdier, long-stemmed forms are used commercially in the cut flower industry. (Full article...)
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Acacia pycnantha, most commonly known as the golden wattle, is a tree of the family Fabaceae. It grows to a height of 8 metres (26 feet) and has phyllodes (flattened leaf stalks) instead of true leaves. The profuse fragrant, golden flowers appear in late winter and spring, followed by long seed pods. Explorer Thomas Mitchell collected the type specimen, from which George Bentham wrote the species description in 1842. The species is native to southeastern Australia as an understorey plant in eucalyptus forest. Plants are cross-pollinated by several species of honeyeater and thornbill, which visit nectaries on the phyllodes and brush against flowers, transferring pollen between them.
A. pycnantha has become a weed in areas of Australia, as well as in Africa and Eurasia. Its bark produces more tannin than any other wattle species, resulting in its commercial cultivation for production of this compound. It has been widely grown as an ornamental garden plant and for cut flower production. A. pycnantha was made the official floral emblem of Australia in 1988, and has been featured on the country's postal stamps. (Full article...)
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Cucurbita fruits come in an assortment of colors and sizes.
Cucurbita (Latin for 'gourd') is a genus of herbaceousfruits in the gourd family, Cucurbitaceae (also known as cucurbits or cucurbi), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and seeds. They are variously known as squash, pumpkin, or gourd, depending on species, variety, and local parlance. Other kinds of gourd, also called bottle-gourds, are native to Africa and belong to the genus Lagenaria, which is in the same family and subfamily as Cucurbita, but in a different tribe. These other gourds are used as utensils or vessels, and their young fruits are eaten much like those of the Cucurbita species.
Most Cucurbita species are herbaceous vines that grow several meters in length and have tendrils, but non-vining "bush" cultivars of C.pepo and C.maxima have also been developed. The yellow or orange flowers on a Cucurbita plant are of two types: female and male. The female flowers produce the fruit and the male flowers produce pollen. Many North and Central American species are visited by specialist beepollinators, but other insects with more general feeding habits, such as honey bees, also visit. (Full article...)
The species was first collected by Humboldt and Bonpland on the outskirts of Mina de Morán in the Sierra de Pachuca of the modern-day Mexican state of Hidalgo on their Latin American expedition of 1799–1804. Based on these collections, Carl Sigismund Kunth described this species in Nova Genera et Species Plantarum in 1817. The extremely variable species has been redefined at least twice since, while several new species have been segregated from it based on various geographical or morphological distinctions, although the legitimacy of some of these is still debated. P. moranensis remains the most common and most widely distributed member of the Section Orcheosanthus. It has long been cultivated for its carnivorous nature and attractive flowers, and is one of the most common butterworts in cultivation. (Full article...)
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Banksia prionotes, commonly known as acorn banksia or orange banksia, is a species of shrub or tree of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 10m (33ft) in height. It can be much smaller in more exposed areas or in the north of its range. This species has serrated, dull green leaves and large, bright flower spikes, initially white before opening to a bright orange. Its common name arises from the partly opened inflorescence, which is shaped like an acorn. The tree is a popular garden plant and also of importance to the cut flower industry.
Banksia prionotes was first described in 1840 by English botanist John Lindley, probably from material collected by James Drummond the previous year. There are no recognised varieties, although it has been known to hybridise with Banksia hookeriana. Widely distributed in south-west Western Australia, B.prionotes is found from Shark Bay (25° S) in the north, south as far as Kojonup (33°50′S). It grows exclusively in sandy soils, and is usually the dominant plant in scrubland or low woodland. Pollinated by birds, it provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months. It is an important source of food for honeyeaters (Meliphagidae), and is critical to their survival in the Avon Wheatbelt region, where it is the only nectar-producing plant in flower at some times of the year. (Full article...)
Isopogon anemonifolius, commonly known as broad-leaved drumsticks, is a shrub of the family Proteaceae that is native only to eastern New South Wales in Australia. It occurs naturally in woodland, open forest, and heathland on sandstone soils. I.anemonifolius usually ranges between one and two metres in height, and is generally smaller in exposed heathland. Its leaves are divided and narrow, though broader than those of the related Isopogon anethifolius, and have a purplish tinge during the cooler months. The yellow flowers appear during late spring or early summer and are displayed prominently. They are followed by round grey cones, which give the plant its common name drumsticks. The small hairy seeds are found in the old flower parts.
A long-lived plant reaching an age of up to 60 years, I.anemonifolius resprouts from its woody base, known as a lignotuber, after bushfire. Seedlings appear in the year following a fire. Although I.anemonifolius was collected by Daniel Solander in 1770, it was not described until 1796 by Richard Salisbury. Several varieties have been named, though none are now recognised as distinct. It was first cultivated in the United Kingdom in 1791. I.anemonifolius grows readily in the garden if located in a sunny or part-shaded spot with sandy soil and good drainage. (Full article...)
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Epacris impressa, also known as common heath, is a species of plant in the heath family Ericaceae. It is native to south-eastern Australia (the states of Victoria, Tasmania, South Australia and New South Wales). French botanist Jacques Labillardière collected the species in 1793 and described it in 1805. Four forms have been identified, but no subspecies are recognised. Growing in heathland, shrubland or open forest, it is generally a small shrub around 0.5 to 1m (1ft 8in to 3ft 3in) tall, with small stiff leaves. The red, pink or white tube-like flowers appear from late autumn to early spring. Honeyeater birds, particularly the eastern spinebill, feed upon the nectar of the flowers. It regenerates after bushfire by seed or by resprouting.
A highly regarded garden plant, the common heath was first cultivated in England in 1825; over seventy named cultivars have been developed, most of which have now vanished. A pink-flowered form, often referred to as "pink heath", is the floral emblem of the state of Victoria. Epacris impressa has proven a difficult plant to propagate reliably, which has limited its use in horticulture and revegetation. It grows best in well-drained but moist soil in a semishaded position. (Full article...)
A cabbage generally weighs between 500 and 1,000 grams (1 and 2lb). 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 (138lb 4oz). 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...)
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The title page of the 1877 edition of Fertilisation of Orchids
Fertilisation of Orchids is a book by English naturalist Charles Darwin published on 15 May 1862 under the full explanatory title On the Various Contrivances by Which British and Foreign Orchids Are Fertilised by Insects, and On the Good Effects of Intercrossing. Darwin's previous book, On the Origin of Species, had briefly mentioned evolutionary interactions between insects and the plants they fertilised, and this new idea was explored in detail. Field studies and practical scientific investigations that were initially a recreation for Darwin—a relief from the drudgery of writing—developed into enjoyable and challenging experiments. Aided in his work by his family, friends, and a wide circle of correspondents across Britain and worldwide, Darwin tapped into the contemporary vogue for growing exotic orchids.
The book was his first detailed demonstration of the power of natural selection, and explained how complex ecological relationships resulted in the coevolution of orchids and insects. The view has been expressed that the book led directly or indirectly to all modern work on coevolution and the evolution of extreme specialisation. It influenced botanists, and revived interest in the neglected idea that insects played a part in pollinating flowers. It opened up the new study areas of pollination research and reproductive ecology, directly related to Darwin's ideas on evolution, and supported his view that natural selection led to a variety of forms through the important benefits achieved by cross-fertilisation. Although the general public showed less interest and sales of the book were low, it established Darwin as a leading botanist. Orchids was the first in a series of books on his innovative investigations into plants. (Full article...)
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Approximate distribution of Hypericum sechmenii within Turkey
Hypericum sechmenii is a perennial herb that usually grows in clusters of stems 3–6 centimeters (1–2 inches) tall and blooms in June and July. The stems of the plant are smooth and lack hairs, while the leaves are leathery and do not have leafstalks. Its flowers are arranged in clusters that form a flat-topped shape known as a corymb, and each flower possesses five bright yellow petals. There are several species that are similar in appearance to H. sechmenii, with only minor physical differences that set them apart. The most closely related of these are Hypericum huber-morathii, Hypericum minutum, and Hypericum thymopsis. (Full article...)
Banksia serrata, commonly known as the saw banksia, the old man banksia, the saw-tooth banksia or the red honeysuckle and as wiriyagan by the Cadigal people, is a species of woody shrub or tree of the genus Banksia, in the family Proteaceae. Native to the east coast of Australia, it is found from Queensland to Victoria with outlying populations on Tasmania and Flinders Island. Commonly growing as a gnarled tree up to 16m (50ft) in height, it can be much smaller in more exposed areas. This Banksia species has wrinkled grey bark, shiny dark green serrated leaves and large yellow or greyish-yellow flower spikes appearing over summer. The flower spikes, or inflorescences, turn grey as they age and pollinated flowers develop into large, grey, woody seed pods called follicles.
B. serrata is one of the four original Banksia species collected by Sir Joseph Banks in 1770, and one of four species published in 1782 as part of Carolus Linnaeus the Younger's original description of the genus. There are no recognised varieties, although it is closely related to Banksia aemula. Throughout its range, it grows exclusively in sandy soil, and is usually the dominant plant in scrubland or low woodland. B. serrata is pollinated by and provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months, and is an important source of food for honeyeaters. It is a common plant of parks and gardens. (Full article...)
The genus has a highly disjunct distribution spread across two major groups of tepuis: the western range in Amazonas and the eastern range in Bolívar. The western range can be further subdivided into two complexes of neighbouring tepuis. The more southerly of these consists of Cerro de la Neblina, Cerro Aracamuni, and Cerro Avispa, and supports four Heliamphora species. The more northerly group of the western range, home to only two species, includes the massive Cerro Duida and neighbouring Cerro Huachamacari and Cerro Marahuaca. The remaining 17–19 species are native to the eastern range, which includes the Aprada Massif, Auyán Massif, Chimantá Massif, Eastern Tepuis chain, Los Testigos chain, and a number of outlying tepuis. Many of the summits of the eastern range are situated on a vast plateau known as the Gran Sabana. Only two species (H.ciliata and H.heterodoxa) are known with certainty from the Gran Sabana, and only H.ciliata is endemic to this habitat. (Full article...)
Cornus is a genus of about 30–60 species of woody plants in the familyCornaceae, commonly known as dogwoods or cornels, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduoustrees or shrubs, but a few species are nearly herbaceous perennial subshrubs, and some species are evergreen. Several species have small heads of inconspicuous flowers surrounded by an involucre of large, typically white petal-like bracts, while others have more open clusters of petal-bearing flowers. The various species of dogwood are native throughout much of temperate and boreal Eurasia and North America, with China, Japan, and the southeastern United States being particularly rich in native species.
Species include the common dogwood Cornus sanguinea of Eurasia, the widely cultivated flowering dogwood (Cornus florida) of eastern North America, the Pacific dogwood Cornus nuttallii of western North America, the Kousa dogwood Cornus kousa of eastern Asia, and two low-growing boreal species, the Canadian and Eurasian dwarf cornels (or bunchberries), Cornus canadensis and Cornus suecica respectively. (Full article...)
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Rafflesia keithii flower
The Rafflesiaceae are a family of rare parasiticplants comprising 36 species in 3 genera found in the tropical forests of east and southeast Asia, including Rafflesia arnoldii, which has the largest flowers of all plants. The plants are endoparasites of vines in the genus Tetrastigma (Vitaceae) and lack stems, leaves, roots, and any photosynthetic tissue. They rely entirely on their host plants for both water and nutrients, and only then emerge as flowers from the roots or lower stems of the host plants. (Full article...)
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Herbicides (US: /ˈɜːrbɪsaɪdz/, UK: /ˈhɜːr-/), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds. Selective herbicides control specific weed species while leaving the desired crop relatively unharmed, while non-selective herbicides (sometimes called "total weed killers") kill plants indiscriminately. The combined effects of herbicides, nitrogen fertilizer, and improved cultivars has increased yields (per acre) of major crops by 3x to 6x from 1900 to 2000.
In the United States in 2012, about 91% of all herbicide usage, determined by weight applied, was in agriculture. In 2012, world pesticide expenditures totaled nearly $24.7 billion; herbicides were about 44% of those sales and constituted the biggest portion, followed by insecticides, fungicides, and fumigants. Herbicide is also used in forestry, where certain formulations have been found to suppress hardwood varieties in favor of conifers after clearcutting, as well as pasture systems. (Full article...)
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Soil fertility refers to the ability of soil to sustain agricultural plant growth, i.e. to provide plant habitat and result in sustained and consistent yields of high quality. It also refers to the soil's ability to supply plant/crop nutrients in the right quantities and qualities over a sustained period of time. A fertile soil has the following properties:
The ability to supply essential plant nutrients and water in adequate amounts and proportions for plant growth and reproduction; and
The absence of toxic substances which may inhibit plant growth e.g. Fe2+ which leads to nutrient toxicity.
The following properties contribute to soil fertility in most situations:
Sufficient soil depth for adequate root growth and water retention;
Good internal drainage, allowing sufficient aeration for optimal root growth (although some plants, such as rice, tolerate waterlogging);
Pollination of fruit trees is required to produce seeds with surrounding fruit. It is the process of moving pollen from the anther to the stigma, either in the same flower or in another flower. Some tree species, including many fruit trees, do not produce fruit from self-pollination, so pollinizer trees are planted in orchards.
The pollination process requires a carrier for the pollen, which can be animal, wind, or human intervention (by hand-pollination or by using a pollen sprayer). Cross pollination produces seeds with a different genetic makeup from the parent plants; such seeds may be created deliberately as part of a selective breeding program for fruit trees with desired attributes. Trees that are cross-pollinated or pollinated via an insect pollinator produce more fruit than trees with flowers that just self-pollinate. In fruit trees, bees are an essential part of the pollination process for the formation of fruit. (Full article...)
Vitis (grapevine) is a genus of 81 accepted species of vining plants in the flowering plant family Vitaceae. The genus consists of species predominantly from the Northern Hemisphere. It is economically important as the source of grapes, both for direct consumption of the fruit and for fermentation to produce wine. The study and cultivation of grapevines is called viticulture.
Most cultivated Vitis varieties are wind-pollinated with hermaphroditic flowers containing both male and female reproductive structures, while wild species are dioecious. These flowers are grouped in bunches called inflorescences. In many species, such as Vitis vinifera, each successfully pollinated flower becomes a grape berry with the inflorescence turning into a cluster of grapes. While the flowers of the grapevines are usually very small, the berries are often large and brightly colored with sweet flavors that attract birds and other animals to disperse the seeds contained within the berries. (Full article...)
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 common sunflower (Helianthus annuus) is a species of large annualforb of the daisy family Asteraceae. The common sunflower is harvested for its edible oily seeds which are used in the production of cooking oil.
The Helianthus annuus has a variety of purposes e.g. food for livestock, bird food, and planted in domestic gardens for aesthetics. The Helianthus annuus is known for its multiple flower heads, whereas the domestic sunflower often possesses a single large flower head atop an unbranched stem. (Full article...)
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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...)
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The Meilland Family is a multi-generational family of French rose breeders. The family's first rosarian was gardener, Joseph Rambaux, who first started breeding roses in 1850 in Lyon. He is best known for developing the Polyantha'Perle d'Or'. His wife, Claudine and son-in-law, Francois Dubreuil, took over the nursery after Rambaux died in 1878. Dubreuil became a successful rose breeder and grower. In 1900, Dubreuil hired sixteen year old, Antoine Meilland, as a gardening assistant, where he met Dubreuil's daughter, Claudia. Antoine and Claudia married in 1909 and their son, Francis was born in 1912. The couple took over Dubreuil's nursery after his death in 1916.
After World War I, Antoine and Claudia bought property in Tassin-la-Demi-Lune, near Lyon and started a new nursery. Their son, Francis, married Marie-Louise (Louisette) Paolino, daughter of an Italian rose breeder in 1939. Francis expanded the rose business over time into a large, international company, and became the most famous and prolific rose breeder in the family. His legendary 'Peace' rose, brought the family international attention and great commercial success when it was introduced after World War II. The Meilland family merged their business with Francisque Richardier in 1946, so that Francis Meilland could focus solely on breeding roses. After Francis's early death in 1958, Louisette continued to breed roses, introducing many awarding winning new varieties. The new company, Meilland-Richardier grew into Meilland International (AKA House of Meilland), and is located in Le Luc en Provence, France. Francis and Louisette's children, Alain and Michele, are both successful rose breeders and continue to manage the company. (Full article...)
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Potato cultivars appear in a variety of colors, shapes, and sizes.
Wild potato species can be found from the southern United States to southern Chile. Genetic studies show that the potato has a single origin, in the area of present-day southern Peru and extreme northwestern Bolivia. Potatoes were domesticated there about 7,000–10,000 years ago from a species in the S. brevicaule complex. Many varieties of the potato are cultivated in the Andes region of South America, where the species is indigenous. (Full article...)
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Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is a form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or specialized reproductive structures, which are sometimes called vegetative propagules.
Many plants naturally reproduce this way, but it can also be induced artificially. Horticulturists have developed asexual propagation techniques that use vegetative propagules to replicate plants. Success rates and difficulty of propagation vary greatly. Monocotyledons typically lack a vascular cambium, making them more challenging to propagate. (Full article...)
Samanea saman, also known as the rain tree or Albizia saman, is a species of flowering tree in the pea family, Fabaceae, that is native to Central and South America. It is a wide-canopied tree with a large umbrella-shaped crown, and usually reaches a height of 15–25m (49–82ft) with a diameter of 30m (98ft). The tree has pinkish flowers with white and red stamens, set on heads with around 12–25 flowers per head. These heads may number in the thousands, covering the whole tree.
Saxifragales (colloquial/plural: the saxifrages) is an order of angiosperms, or flowering plants, containing 15 botanical families and around 100 genera, with nearly 2,500 species. Of the 15 families, many are small, with eight of them being monotypic (having only a single genus). The largest family is the Crassulaceae (stonecrops), a diverse group of mostly succulent plants, with about 35 genera. Saxifragales are found worldwide, primarily in temperate to subtropical zones, rarely being encountered growing wild in the tropics; however, many species are now cultivated throughout the world as knowledge of plant husbandry has improved. They can be found in a wide variety of environments, from deserts to fully aquatichabitats, with species adapted to alpine, forested or fully-aquatic habitats. Many are epiphytic or lithophytic, growing on exposed cliff faces, on trees or on rocks, and not requiring a highly organic or nutrient-dense substrate to thrive.
Globally, the saxifrages have a wide variety of uses by humans, ranging from textiles and timber to foodstuffs. Several families—such as the aforementioned Crassulaceae—and genera are of significant commercial importance in some countries and economies, being cultivated on a large scale for sale as ornamental plants. Apart from ornamentals, another highly-prized group are the Grossulariaceae (currants and gooseberries), particularly blackcurrants, redcurrants and white currants. (Full article...)
The earliest historical records of herbs are found from the Sumerian civilization, where hundreds of medicinal plants including opium are listed on clay tablets, c.3000 BC. The Ebers Papyrus from ancient Egypt, c.1550 BC, describes over 850 plant medicines. The Greek physician Dioscorides, who worked in the Roman army, documented over 1000 recipes for medicines using over 600 medicinal plants in De materia medica, c.60 AD; this formed the basis of pharmacopoeias for some 1500 years. Drug research sometimes makes use of ethnobotany to search for pharmacologically active substances, and this approach has yielded hundreds of useful compounds. These include the common drugs aspirin, digoxin, quinine, and opium. The compounds found in plants are diverse, with most in four biochemical classes: alkaloids, glycosides, polyphenols, and terpenes. Few of these are scientifically confirmed as medicines or used in conventional medicine. (Full article...)
Cultivar belonging to the Schlumbergera Truncata Group
Schlumbergera is a small genus of cacti with six to nine species found in the coastal mountains of south-eastern Brazil. These plants grow on trees or rocks in habitats that are generally shady with high humidity, and can be quite different in appearance from their desert-dwelling cousins. Most species of Schlumbergera have stems which resemble leaf-like pads joined one to the other and flowers which appear from areoles at the joints and tips of the stems. Two species have cylindrical stems more similar to other cacti.
Common names for these cacti generally refer to their flowering season. In the Northern Hemisphere, they are called Christmas cactus, Thanksgiving cactus, crab cactus and holiday cactus. In Brazil, the genus is referred to as Flor de Maio (May flower), reflecting the period in which they flower in the Southern Hemisphere. Most of the popular houseplants are cultivars of Schlumbergera, rather than species, with flowers in white, pink, yellow, orange, red or purple. The Easter cactus or Whitsun cactus, placed in the genus Rhipsalidopsis, is also called a holiday cactus and has flowers in red, orange, pink and white. (Full article...)
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Clusters of Bidni olives ripening on the tree
The Bidni, which is also referred to as Bitni, is an olive cultivar from the Mediterranean island of Malta. The fruit is small in size, hearty with a "violet colour", and is renowned for its superior oil which is low in acidity. The latter is generally attributed to the poor quality alkaline soil found on the Maltese Islands. As an indigenous olive cultivar, the Bidni has developed a unique DNA profile, and is believed to be among the most ancient species on the island, triggering local authorities to declare some of these ancient trees as "national monuments", and as having an "Antiquarian Importance", a status which is enjoyed by only a handful of other species. (Full article...)
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Einar Du Rietz in 1932
Gustaf Einar Du Rietz (25 April 1895 – 7 March 1967) was a Swedish botanist and lichenologist. His research interests included plant ecology, lichen taxonomy, and biogeography. He was a leading figure in the Uppsala school of phytosociology–the study of groups of species of plants that are usually found together–and is recognised for his role in advancing this field of science and for mentoring future lichenologists. He led the Swedish Australasian Botanical Expedition of 1926–27, a seven-month research tour of various locations. He was married to Greta Sernander, who was also a lichenologist. During the expedition, Du Rietz and his wife researched the vegetation in New Zealand, Australia, and Java, focusing on mountain lichens and their potential as bioindicators for environmental conditions. They collected around 3000 specimens, contributing significantly to the study of bipolar lichens and forest ecology, despite challenges in processing all the samples upon return to Sweden. Several species have been named in his honour. In 1949, Du Rietz was elected to the Royal Swedish Academy of Sciences and contributed significantly to nature conservation efforts in Sweden. (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...)
The parsnip (Pastinaca sativa) is a root vegetable closely related to carrot and parsley, all belonging to the flowering plant family Apiaceae. It is a biennial plant usually grown as an annual. Its long taproot has cream-colored skin and flesh, and, left in the ground to mature, becomes sweeter in flavor after winter frosts. In its first growing season, the plant has a rosette of pinnate, mid-green leaves. If unharvested, it produces a flowering stem topped by an umbel of small yellow flowers in its second growing season, later producing pale brown, flat, winged seeds. By this time, the stem has become woody, and the tap root inedible. Precautions should be taken when handling the stems and foliage, as parsnip sap can cause a skin rash or even blindness if exposed to sunlight after handling.
The parsnip is native to Eurasia; it has been used as a vegetable since antiquity and was cultivated by the Romans, although some confusion exists between parsnips and carrots in the literature of the time. It was used as a sweetener before the arrival of cane sugar in Europe. (Full article...)
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The poinsettia (/pɔɪnˈsɛt(i)ə/; Euphorbia pulcherrima) is a commercially important flowering plant species of the diverse spurge family Euphorbiaceae. Indigenous to Mexico and Central America, the poinsettia was first described by Europeans in 1834. It is particularly well known for its red and green foliage and is widely used in Christmas floral displays. It derives its common English name from Joel Roberts Poinsett, the first United States minister to Mexico, who is credited with introducing the plant to the US in the 1820s. Poinsettias are shrubs or small trees, with heights of 0.6 to 4m (2.0 to 13.1ft). Though often stated to be highly toxic, the poinsettia is not dangerous to pets or children. Exposure to the plant, even consumption, most often results in no effect, though it can cause nausea, vomiting, or diarrhea.
Wild poinsettias occur from Mexico to southern Guatemala, growing on mid-elevation, Pacific-facing slopes. One population in the Mexican state of Guerrero is much further inland, however, and is thought to be the ancestor of most cultivated populations. Wild poinsettia populations are highly fragmented, as their habitat is experiencing largely unregulated deforestation. They were cultivated by the Aztecs for use in traditional medicine. They became associated with the Christmas holiday and are popular seasonal decorations. Every year in the United States, approximately 70 million poinsettias of many cultivated varieties are sold in a six-week period. Many of these poinsettias are grown by Paul Ecke Ranch, which serves half the worldwide market and 70 percent of the US market. (Full article...)
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White trillium blooming in Backus Woods (Ontario, Canada).
Trillium grandiflorum is most common in rich, mixed upland forests. It is easily recognised by its attractive three-petaled white flowers, opening from late spring to early summer, that rise above a whorl of three leaf-like bracts. It is an example of a spring ephemeral, a plant whose life-cycle is synchronised with that of the deciduous woodland which it favours. (Full article...)
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Portrait by Spiridione Gambardella
Sir William Jackson HookerKHFRSFRSEFLSDCL (6 July 1785–12 August 1865) was an English botanist and botanical illustrator, who became the first director of Kew when in 1841 it was recommended to be placed under state ownership as a botanic garden. At Kew he founded the Herbarium and enlarged the gardens and arboretum. The standard author abbreviationHook. is used to indicate this person as the author when citing a botanical name.[1] Hooker was born and educated in Norwich. An inheritance gave him the means to travel and to devote himself to the study of natural history, particularly botany. He published his account of an expedition to Iceland in 1809, even though his notes and specimens were destroyed during his voyage home. He married Maria, the eldest daughter of the Norfolk banker Dawson Turner, in 1815, afterwards living in Halesworth for 11 years, where he established a herbarium that became renowned by botanists at the time. (Full article...)
An evergreenperennial, it originates from the Arabian Peninsula, but also grows wild in tropical, semi-tropical, and arid climates around the world. It is cultivated for commercial products, mainly as a topical treatment used over centuries. The species is considered attractive for decorative purposes, and is often used indoors as a potted plant. (Full article...)
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Myco-heterotrophy (from Greekμύκηςmýkes'fungus', ἕτεροςhéteros'another', 'different' and τροφήtrophé'nutrition') is a symbiotic relationship between certain kinds of plants and fungi, in which the plant gets all or part of its food from parasitism upon fungi rather than from photosynthesis. A myco-heterotroph is the parasitic plant partner in this relationship. Myco-heterotrophy is considered a kind of cheating relationship and myco-heterotrophs are sometimes informally referred to as "mycorrhizal cheaters". This relationship is sometimes referred to as mycotrophy, though this term is also used for plants that engage in mutualisticmycorrhizal relationships. (Full article...)
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Richard Buxton (15 January 1785 – 2 January 1865) was a British shoemaker and amateur botanist. Born in Prestwich, Lancashire, to a family who lived in humble circumstances, he taught himself to read, and learned the basic principles of botany. Although living as a pauper for most of his life, in 1849 he published A Botanical Guide to the Flowering Plants, Ferns, Mosses and Algæ, Found Indigenous Within Sixteen Miles of Manchester, which became one of the standard texts on the flora then commonly found in the Manchester area. According to his obituary in the Journal of Botany, British and Foreign, Buxton was one of "nature's gentlemen" and "his true and correct pronunciation of scientific terms have caused many who heard him to believe he was an accomplished classical scholar". He was acknowledged by the geologist Edward William Binney as "the most profound thinker of his class". (Full article...)
... that plant biology professor Luca Comai independently developed glyphosate-resistant plants while working at Calgene and published his research before Monsanto researchers were able to?
... that New York City's Bartow–Pell Mansion became a museum after its operator was restricted from importing and exporting plants?
... that residents at Alterlaa, a housing complex in Vienna, have large concrete planters in which plants can be grown?
... 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 in the late 2000s the Campbell Soup Company began producing a spicier canned cheese sauce in their California and Texas plants than they did elsewhere to cater for different consumer tastes?
... that according to Lois N. Magner, Hildegard of Bingen's Physica is "probably the first book by a female author to discuss the elements and the therapeutic virtues of plants, animals, and metals"?
The following are images from various plant-related articles on Wikipedia.
Image 1The food we eat comes directly or indirectly from plants such as rice. (from Botany)
Image 21 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 10The 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 11Five of the key areas of study within plant physiology (from Botany)
Image 12Micropropagation of transgenic plants (from Botany)
Image 15Structure 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 17The 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 24A 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: 20μm (from Evolutionary history of plants)
Image 25Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 33The Linnaean Garden of Linnaeus' residence in Uppsala, Sweden, was planted according to his Systema sexuale. (from Botany)
Image 34The 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 35Structure of a plant cell (from Plant cell)
Image 37The 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)
This article uses material from the Wikipedia article Portal:Botany, and is written by contributors.
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