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 eat plants directly or rely on organisms which do so. (Full article...)
Banksia violacea, commonly known as violet banksia, is a species of shrub or tree in the plant genus Banksia (family Proteaceae). It generally grows as a small shrub to 1.5 m (5 ft) high with fine narrow leaves, and is best known for its unusually coloured dark purple-violet inflorescences. The colour of the inflorescences, short leaves, and flattened follicles which are sticky when young, help identify this species from others in the field. It is found in low shrubland in southern regions of Western Australia from Esperance in the east to Narrogin in the west, growing exclusively in sandy soils.
First described in 1927 by the West Australian botanist Charles Gardner, the species was at one stage considered a variety of B. sphaerocarpa. Although there are no recognised subspecies or varieties, both lignotuberous and nonlignotuberous forms exist for Banksia violacea. Wasps, ants and flies have been recorded visiting flower spikes. Banksia violacea is classified as Not Threatened under the Wildlife Conservation Act of Western Australia. Regarded as of little value to floriculture, it is rarely cultivated. (Full article...)
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A field of iceberg lettuces in California
Lettuce (Lactuca sativa) is an annual plant of the family Asteraceae mostly grown as a leaf vegetable. The leaves are most often used raw in green salads, although lettuce is also seen in other kinds of food, such as sandwiches, wraps and soups; it can also be grilled. Its stem and seeds are sometimes used; celtuce (asparagus lettuce) is one variety grown for its stems, which are eaten either raw or cooked. In addition to its main use as a leafy green, it has also gathered religious and medicinal significance over centuries of human consumption. Europe and North America originally dominated the market for lettuce, but by the late 20th century the consumption of lettuce had spread throughout the world. In 2023, world production of lettuce (and chicory) was 28 million tonnes, led by China with 53% of the total.
Lettuce was originally farmed by the ancient Egyptians, who transformed it from a plant whose seeds were used to obtain oil into an important food crop raised for its succulent leaves and oil-rich seeds. Lettuce spread to the Greeks and Romans; the latter gave it the name lactuca, from which the English lettuce is derived. By 50 AD, many types were described, and lettuce appeared often in medieval writings, including several herbals. The 16th through 18th centuries saw the development of many varieties in Europe, and by the mid-18th century, cultivars were described that can still be found in modern gardens. (Full article...)
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Second-year plant starting to flower, with a dead stem of the previous year, behind left
Verbascum thapsus, the great mullein, greater mullein or common mullein, is a species of mullein native to Europe, northern Africa, and Asia, and introduced in the Americas, Australia and New Zealand.
It is a hairy biennial plant that can grow to 2 m tall or more. Its small, yellow flowers are densely grouped on a tall stem, which grows from a large rosette of leaves. It grows in a wide variety of habitats, but prefers well-lit, disturbed soils, where it can appear soon after the ground receives light, from long-lived seeds that persist in the soil seed bank. It is a common weedy plant that spreads by prolifically producing seeds, and has become invasive in temperate world regions. It is a minor problem for most agricultural crops, since it is not a competitive species, being intolerant of shade from other plants and unable to survive tilling. It also hosts many insects, some of which can be harmful to other plants. Although individuals are easy to remove by hand, populations are difficult to eliminate permanently. (Full article...)
Banksia paludosa, commonly known as the marsh or swamp banksia, is a species of shrub in the plantgenusBanksia. It is native to New South Wales, Australia, where it is found between Sydney and Batemans Bay, with an isolated population further south around Eden. There are two recognised subspecies, the nominate of which is a spreading shrub to 1.5 m (4.9 ft) in height, and subsp. astrolux is a taller shrub to 5 m (16 ft) high found only in Nattai National Park.
Native mammals, such as the brown antechinus and sugar glider, are important pollinators of B. paludosa. Several species of honeyeaters visit the flower spikes, as do ants and the European honey bee. The response to bushfire depends on the subspecies; subspecies paludosa regenerates from underground lignotubers, while plants of subspecies astrolux are killed by fire and regenerate from large stores of seed which have been held in cones in the plant canopy. B. paludosa is sometimes seen in cultivation, with dwarf forms being registered and sold. (Full article...)
Banksia menziesii, commonly known as firewood banksia, is a species of flowering plant in the family Proteaceae. It is a gnarled tree up to 10 m (33 ft) tall, or a lower spreading 1–3 m (3.3–9.8 ft) shrub in the more northern parts of its range. The serrated leaves are dull green with new growth a paler grey green. The prominent autumn and winter inflorescences are often two-coloured red or pink and yellow, and their colour has given rise to more unusual common names such as port wine banksia and strawberry banksia. Yellow blooms are rarely seen.
First described by the botanist Robert Brown in the early 19th century, no separate varieties of Banksia menziesii are recognised. It is found in Western Australia, from the Perth (32° S) region north to the Murchison River (27° S), and generally grows on sandy soils, in scrubland or low woodland. Banksia menziesii provides food for a wide array of invertebrate and vertebrate animals; birds and in particular honeyeaters are prominent visitors. A relatively hardy plant, Banksia menziesii is commonly seen in gardens, nature strips and parks in Australian urban areas with Mediterranean climates, but its sensitivity to dieback from the soil-borne water mould Phytophthora cinnamomi makes it short-lived in places with humid summers, such as Sydney. Banksia menziesii is widely used in the cut flower industry both in Australia and overseas. (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 30 cm (12 in) long, or lanceolate (spear-shaped) and up to 15 cm (5.9 in) 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...)
Ficus obliqua, commonly known as the small-leaved fig, is a tree in the family Moraceae, native to eastern Australia, New Guinea, eastern Indonesia to Sulawesi and islands in the southwestern Pacific Ocean. Previously known for many years as Ficus eugenioides, it is a banyan of the genus Ficus, which contains around 750 species worldwide in warm climates, including the edible fig (Ficus carica). Beginning life as a seedling, which grows on other plants (epiphyte) or on rocks (lithophyte), F. obliqua can grow to 60 m (200 ft) high and nearly as wide with a pale grey buttressed trunk, and glossy green leaves.
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 is often erroneously credited with producing 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...)
The fruits are small, round, and yellow, and can ripen and turn red at any time of year, peaking in spring and summer. Like all figs, the fruit is in the form of a syconium, an inverted inflorescence with the flowers lining an internal cavity. F. rubiginosa is exclusively pollinated by the fig wasp species Pleistodontes imperialis, which may comprise four cryptospecies. The syconia are also home to another fourteen species of wasp, some of which induce galls while others parasitise the pollinator wasps and at least two species of nematode. Many species of bird, including pigeons, parrots, and various passerines, eat the fruit. Ranging along the Australian east coast from Queensland to Bega in southern New South Wales (including the Port Jackson area, leading to its alternative name), F. rubiginosa grows in rainforest margins and rocky outcrops. It is used as a shade tree in parks and public spaces, and when potted is well-suited for use as an indoor plant or in bonsai. (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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Inflorescence
Banksia speciosa, commonly known as the showy banksia, is a species of large shrub or small tree in the familyProteaceae. It is found on the south coast of Western Australia between Hopetoun (34° S 120° E) and Point Culver (33° S 124° E), growing on white or grey sand in shrubland. Reaching up to 8 m (26 ft) in height, it is a single-stemmed plant that has thin leaves with prominent triangular 'teeth' along each margin, which are 20–45 cm (7.9–17.7 in) long and 2–4 cm (0.8–1.6 in) wide. The prominent cream-yellow flower spikes known as inflorescences appear throughout the year. As they age they develop up to 20 follicles each that store seeds until opened by fire. Though widely occurring, the species is highly sensitive to dieback and large populations of plants have succumbed to the disease.
Collected and described by Robert Brown in the early 19th century, B. speciosa is classified in the seriesBanksia within the genus. Its closest relative is B. baxteri. B. speciosa plants are killed by bushfire, and regenerate from seed. The flowers attract nectar- and insect-feeding birds, particularly honeyeaters, and a variety of insects. In cultivation, B. speciosa grows well in a sunny location on well-drained soil in areas with dry summers. It cannot be grown in areas with humid summers, though it has been grafted onto Banksia serrata or B. integrifolia. (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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Persoonia levis, commonly known as the broad-leaved geebung, is a shrub native to New South Wales and Victoria in eastern Australia. It reaches 5 m (16 ft) in height and has dark grey papery bark and bright green asymmetrical sickle-shaped leaves up to 14 cm (5.5 in) long and 8 cm (3.2 in) wide. The small yellow flowers appear in summer and autumn (December to April), followed by small green fleshy fruit, which are classified as drupes. Within the genus Persoonia, it is a member of the Lanceolata group of 58 closely related species. P. levis interbreeds with several other species where they grow together.
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...)
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...)
Edith Gertrude Clements (1874–1971), also known as Edith S. Clements and Edith Schwartz Clements, was an American botanist and pioneer of botanical ecology who was the first woman to be awarded a Ph.D. by the University of Nebraska. She was married to botanist Frederic Clements, with whom she collaborated throughout her professional life. Together they founded the Alpine Laboratory, a research station at Pikes Peak, Colorado. Clements was also a botanical artist who illustrated her own books as well as joint publications with Frederic.
Both Clementses were involved with the study of phytogeography, especially those factors determining the ecology of vegetation in particular regions, and they would be praised as "the most illustrious husband-wife team since the Curies." It is impossible to entirely disentangle the work of each Clementses as they worked together during their noteworthy years. (Full article...)
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Taraxacum (/təˈræksəkəm/) is a genus of flowering plants in the family Asteraceae, which consists of species commonly known as dandelions. The scientific and hobby study of the genus is known as taraxacology. The genus has a near-cosmopolitan distribution, absent only from tropical and polar areas. Two of the most common species worldwide, T. officinale (the common dandelion) and T. erythrospermum (the red-seeded dandelion), are European species introduced into North America, where they are non-native. Dandelions thrive in temperate regions and can be found in yards, gardens, sides of roads, among crops, and in many other habitats.
Like other members of the family Asteraceae, they have very small flowers collected together into a composite flower head. Each single flower in a head is called a floret. In part due to their abundance, along with being a generalist species, dandelions are one of the most vital early spring nectar sources for a wide host of pollinators. Many Taraxacum species produce seeds asexually by apomixis, where the seeds are produced without pollination, resulting in offspring that are genetically identical to the parent plant. (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 cultivated 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...)
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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Rosa Morning Jewel (1968) James Cocker and Sons is a nursery business located in Aberdeen, Scotland. Founded in 1841 (184 years ago) (1841) by James Cocker, the company has been owned by the Cocker family for five generations. During the last seventy years, the nursery has introduced more than 100 new rose varieties and holds Royal Warrants from Queen Elizabeth, the Queen Mother, and the Prince of Wales. James Cocker & Sons is best known for creating the hybrid tea rose, 'Silver Jubilee', the popular rose named in honour of the Queen's 25 years reign. The rose was developed by Alec Cocker, and introduced by his wife, Anne Cocker, after Alec's death in 1977. Anne continued to breed roses and manage the company until she was in her eighties. She won multiple horticultural awards and was internationally recognized for her work. (Full article...)
Safflower (Carthamus tinctorius) is a highly branched, herbaceous, thistle-like annual plant in the family Asteraceae. It is one of the world's oldest crops; today, it is commercially cultivated for vegetable oil extracted from the seeds. Plants are 30 to 150 cm (12 to 59 in) tall with globular flower heads having yellow, orange, or redflowers. Each branch will usually have from one to five flower heads containing 15 to 20 seeds per head. Safflower is native to arid environments having seasonal rain. It grows a deep taproot which enables it to thrive in such environments. (Full article...)
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Vegetables in a market in the Philippines Vegetables are edible parts of plants that are consumed by humans or other animals as food. This original meaning is still commonly used, and is applied to plants collectively to refer to all edible plant matter, including flowers, fruits, stems, leaves, roots, and seeds. An alternative definition is applied somewhat arbitrarily, often by culinary and cultural tradition; it may include savoury fruits such as tomatoes and courgettes, flowers such as broccoli, and seeds such as pulses, but exclude foods derived from some plants that are fruits, flowers, nuts, and cereal grains.
Originally, vegetables were collected from the wild by hunter-gatherers and entered cultivation in several parts of the world, probably during the period 10,000 BC to 7,000 BC, when a new agricultural way of life developed. At first, plants that grew locally were cultivated, but as time went on, trade brought common and exotic crops from elsewhere to add to domestic types. Nowadays, most vegetables are grown all over the world as climate permits, and crops may be cultivated in protected environments in less suitable locations. China is the largest producer of vegetables, and global trade in agricultural products allows consumers to purchase vegetables grown in faraway countries. The scale of production varies from subsistence farmers supplying the needs of their family for food, to agribusinesses with vast acreages of single-product crops. Depending on the type of vegetable concerned, harvesting the crop is followed by grading, storing, processing, and marketing. (Full article...)
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Succulent plants have thickened stems or leaves, such as this Aloe.
In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions.
Succulents may store water in various structures, such as leaves and stems. The water content of some succulent organs can get up to 90–95%, such as Glottiphyllum semicyllindricum and Mesembryanthemum barkleyii. Some definitions also include roots, thus geophytes that survive unfavorable periods by dying back to underground storage organs (caudex) may be regarded as succulents. The habitats of these water-preserving plants are often in areas with high temperatures and low rainfall, such as deserts, but succulents may be found even in alpine ecosystems growing in rocky or sandy soil. Succulents are characterized by their ability to thrive on limited water sources, such as mist and dew, which makes them equipped to survive in ecosystems that contain scarce water sources. (Full article...)
Iris is a flowering plantgenus of 310 accepted species with showy flowers. As well as being the scientific name, iris is also widely used as a common name for all Iris species, as well as some belonging to other closely related genera. A common name for some species is flags, while the plants of the subgenusScorpiris are widely known as junos, particularly in horticulture. It is a popular garden flower.
A selection of antique herbal medicines Herbal medicine (also called herbalism, phytomedicine or phytotherapy) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. Scientific evidence for the effectiveness of many herbal treatments remains limited, prompting ongoing regulatory evaluation and research into their safety and efficacy. Standards for purity or dosage are generally not provided. The scope of herbal medicine sometimes includes fungal and bee products, as well as minerals, shells and certain animal parts.
Paraherbalism is the pseudoscientific use of plant or animal extracts as medicine, relying on unproven beliefs about the safety and effectiveness of minimally processed natural substances. (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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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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An ethylene signal transduction pathway. Ethylene permeates the cell membrane and binds to a gasoreceptor on the endoplasmic reticulum. The gasoreceptor 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 a 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...)
White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all harvested from two of the five varieties which form the main crops now grown, 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...)
A bean is the seed of plants in many genera of the legume family (Fabaceae) used as a vegetable for human consumption or animal feed. The seeds are sold fresh or preserved through drying (a pulse). Beans have been cultivated since the seventh millenium BCE in Thailand, and since the second millennium BCE in Europe and in Peru. Most beans, with the exception of peas, are summer crops. As legumes, the plants fix nitrogen and form seeds with a high protein content. They are produced on a scale of millions of tons annually in many countries; India is the largest producer.
Dried beans are traditionally soaked and boiled, and used in traditional dishes throughout the world including salads, soups, and stews such as chili con carne. Some are processed into tofu; others are fermented to form tempeh. Guar beans are used for their gum. The unripe seedpods of some varieties are also eaten whole as green beans or edamame (immature soybean). Some types are sprouted to form beansprouts. (Full article...)
Yucca (/ˈjʌkə/YUCK-uh) is both the scientific name and common name for a genus native to North America from Panama to southern Canada. It contains 50 accepted species. In addition to yucca, they are also known as Adam's needle or Spanish-bayonet. The genus is generally classified in the asparagus family in a subfamily with the Agave, though historically it was part of the lily family. The species range from small shrubby plants to tree-like giants, such as the Joshua tree. All yuccas have rosettes of leaves that taper to points and inflorescences with many flowers that are mainly cream white with thick petals. Though adapted to a wide range of climates the plants are xerophytes, ones that specialize in dry living conditions.
The tight relationship between the yucca plants and their pollinators, the yucca moths from the genera Tegeticula and Parategeticula, is a well known example of evolutionary mutualism. They are an important part of the ecology of North American deserts, providing shelter to small animals and creating habitats. The human uses of yuccas include garden plants, as food, and for extracts. The flower petals of various species are eaten as a part of local cuisine, particularly in Central America and Mexico. Historically, the yucca was extensively used for its fibers to make cords, baskets, mats, and sandals. It continues to be used by native peoples for traditional soaps. (Full article...)
This grape variety appeared in France in the 17th century as a result of natural crossbreeding. 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 viticulture hazards. (Full article...)
Before molecular analyses recovered this clade, evolutionary biologist Thomas Cavalier-Smith had already hypothesized an evolutionary proximity between plants and the remaining groups (collectively known as 'chromalveolates' in his classification system). He coined the term photokaryotes for these organisms, as they include almost all of the photosynthetic eukaryotes. He later called them corticates due to the presence of cortical alveoli in many of their members. (Full article...)
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The canopy of Simarouba amara
Simarouba amara is a species of tree in the family Simaroubaceae, found in the rainforests and savannahs of South and Central America and the Caribbean. It was first described by Aubl. in French Guiana in 1775 and is one of six species of Simarouba. The tree is evergreen, but produces a new set of leaves once a year. It requires relatively high levels of light to grow and grows rapidly in these conditions, but lives for a relatively short time. In Panama, it flowers during the dry season in February and March, whereas in Costa Rica, where there is no dry season it flowers later, between March and July. As the species is dioecious, the trees are either male or female and only produce male or female flowers. The small yellow flowers are thought to be pollinated by insects, the resulting fruits are dispersed by animals including monkeys, birds and fruit-eating bats and the seeds are also dispersed by leaf cutter ants.
Simarouba amara has been studied extensively by scientists in an attempt to understand the tree and also to gain a better understanding of the ecology of the rainforest in general. Many of these studies were conducted on Barro Colorado Island in Panama or at La Selva Biological Station in Costa Rica. Of particular interest is how it competes with other species and with individuals of the same species at different stages in its life cycle. The seedlings are normally limited by the amount of light and nutrients found where they are growing and the saplings are considered relatively light demanding compared to other species. Young individuals are more likely to survive when they grow further away from their parents and when there are few other individuals growing near to them, which may be due to them being able to escape diseases. Plant physiologists have investigated how the leaves of the tree differ depending on their location in the forest canopy finding they are thicker in the canopy and thinner in the understory. They have also measured how the water potential of their leaves changes and when their stomata open and close during the day; the findings suggest that rather than closing their stomata to control water loss, it is controlled by the leaf area instead. Population geneticists have examined the way in which its genes vary, at both the local scale and across its range using microsatellites. It is genetically diverse, indicating gene flow occurs between populations and seeds can be dispersed up to 1 km. The leaves of S. amara are eaten by several species of caterpillar, particularly those in the genus Atteva. Several species of termite and ants live on or around the tree and lianas and epiphytes grow on the tree. (Full article...)
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Vegetables in a market in the Philippines Vegetables are edible parts of plants that are consumed by humans or other animals as food. This original meaning is still commonly used, and is applied to plants collectively to refer to all edible plant matter, including flowers, fruits, stems, leaves, roots, and seeds. An alternative definition is applied somewhat arbitrarily, often by culinary and cultural tradition; it may include savoury fruits such as tomatoes and courgettes, flowers such as broccoli, and seeds such as pulses, but exclude foods derived from some plants that are fruits, flowers, nuts, and cereal grains.
Originally, vegetables were collected from the wild by hunter-gatherers and entered cultivation in several parts of the world, probably during the period 10,000 BC to 7,000 BC, when a new agricultural way of life developed. At first, plants that grew locally were cultivated, but as time went on, trade brought common and exotic crops from elsewhere to add to domestic types. Nowadays, most vegetables are grown all over the world as climate permits, and crops may be cultivated in protected environments in less suitable locations. China is the largest producer of vegetables, and global trade in agricultural products allows consumers to purchase vegetables grown in faraway countries. The scale of production varies from subsistence farmers supplying the needs of their family for food, to agribusinesses with vast acreages of single-product crops. Depending on the type of vegetable concerned, harvesting the crop is followed by grading, storing, processing, and marketing. (Full article...)
Erythranthe, the monkey-flowers and musk-flowers, is a diverse plantgenus with more than 120 members (as of 2022) in the familyPhrymaceae. Erythranthe was originally described as a separate genus, then generally regarded as a section within the genus Mimulus, and recently returned to generic rank. Mimulus sect. Diplacus was segregated from Mimulus as a separate genus at the same time. Mimulus remains as a small genus of eastern North America and the Southern Hemisphere. Molecular data show Erythranthe and Diplacus to be distinct evolutionary lines that are distinct from Mimulus as strictly defined, although this nomenclature is controversial.
Member species are usually annuals or herbaceousperennials. Flowers are red, pink, or yellow, often in various combinations. A large number of the Erythranthe species grow in moist to wet soils with some growing even in shallow water. They are not very drought resistant, but many of the species now classified as Diplacus are. Species are found at elevations from oceanside to high mountains as well as a wide variety of climates, though most prefer wet areas such as riverbanks. (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 that of 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 early volumes (IV to XV) are on quadrupeds. The next group (XVI to XXIV) are on birds, followed by a group on minerals (XXV to XXIX). There followed a group of supplements on geology and related subjects, with additional quadrupeds (XXX to XXXVI). Further supplements covered the reptiles (XXXVII to XXXVIII) and fishes (XXXIX to XXXXIII). Finally there was a volume on cetaceans (XXXXIV). The work was republished in various editions in France, and was translated into languages including English, German, Swedish, Italian, and Russian. (Full article...)
The species was described by Werner Greuter in 1965 as Elodes acifera, and was later placed into section Adenotrias of the genus Hypericum by Norman Robson in 1984. Hypericum aciferum has an extremely limited distribution in the southwest corner of Crete, and is found in rock crevices. It was assessed as endangered several times in the 1980s and 1990s, due to a small population and threats from grazing and fire. It was protected by the European Environment Agency, and a plant micro-reserve was established to conserve it in 2015. The International Union for Conservation of Nature re-assessed H. aciferum as vulnerable in 2021 and recorded its population as stable. The plant is not used by humans for ornamental or pharmaceutical purposes. (Full article...)
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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...)
The lemon (Citrus × limon) is a species of small evergreen tree in the Citrus genus of the flowering plant family Rutaceae. A true lemon is a hybrid of the citron and the bitter orange. Its origins are uncertain, but some evidence suggests lemons originated during the 1st millennium BC in what is now northeastern India. Some other citrus fruits are called lemon.
The yellow fruit of the lemon tree is used throughout the world, primarily for its juice. The pulp and rind are used in cooking and baking. The juice of the lemon is about 5–6% citric acid, giving it a sour taste. This makes it a key ingredient in drinks and foods such as lemonade and lemon meringue pie. (Full article...)
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John Hunter Thomas (March 26, 1928 – July 20, 1999) was an American botanist, professor of biological sciences at Stanford University, curator and director of the Dudley Herbarium, and joint curator at the California Academy of Sciences. He was known for his study of plants in the Sonoran Desert, the Santa Cruz Mountains, and the Alaska North Slope, and for his history of botanical exploration in Washington, Oregon, and California. His doctoral research on the plants of the Santa Cruz Mountains was published as a guide to the vascular plants of coastal, central California, and was recognized as a standard reference work for regional flora. It was used for decades as teaching material for courses in systematic botany and the ecology of vascular plants at Stanford. Thomas helped establish the Jasper Ridge Biological Preserve and was a primary contributor to what later became the Jasper Ridge Oakmead Herbarium (JROH). In total, Thomas collected more than 20,000 plant specimens for herbaria throughout his career. (Full article...)
... 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 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?
Image 4Five of the key areas of study within plant physiology (from Botany)
Image 51 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 16Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 17Leaf lamina. The megaphyllous leaf architecture arose multiple times in different plant lineages (from Evolutionary history of plants)
Image 18Structure of a plant cell (from Plant cell)
Image 19A 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 21A botanist preparing a plant specimen for mounting in the herbarium (from Botany)
Image 22A 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 23Transverse section of a fossil stem of the Devonian vascular plant Rhynia gwynne-vaughani (from Botany)
Image 29Structure 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 30The 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 food we eat comes directly or indirectly from plants such as rice. (from Botany)
Image 32Paper chromatography of some spinach leaf extract shows the various pigments present in their chloroplasts: yellowish xanthophylls, greenish chlorophylls a and b. (from Botany)
Image 33The 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 34Micropropagation of transgenic plants (from Botany)
Image 35The 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)