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...)
The floral emblem for its home state of New South Wales, Telopea speciosissima has featured prominently in art, architecture, and advertising, particularly since Australian federation. Commercially grown in several countries as a cut flower, it is also cultivated in home gardens, requiring good drainage yet adequate moisture, but is vulnerable to various fungal diseases and pests. A number of cultivars with various shades of red, pink and even white flowers are available. Horticulturists have also developed hybrids with T. oreades and T. mongaensis which are more tolerant of cold, shade, and heavier soils. (Full article...)
Banksia ericifolia, the heath-leaved banksia, or lantern banksia, is a species of woody shrub of the family Proteaceae native to Australia. It grows in two separate regions of Central and Northern New South Wales east of the Great Dividing Range. Well known for its orange or red autumn inflorescences, which contrast with its green fine-leaved heath-like foliage, it is a medium to large shrub that can reach 6 m (20 ft) high and wide, though is usually half that size. In exposed heathlands and coastal areas, it is more often 1–2 m (3.3–6.6 ft).
Banksia ericifolia was one of the original Banksia species collected by Joseph Banks around Botany Bay in 1770 and was named by Carl Linnaeus the Younger, son of Carl Linnaeus, in 1782. A distinctive plant, it has split into two subspecies: Banksia ericifolia subspecies ericifolia of the Sydney region and Banksia ericifolia subspecies macrantha of the New South Wales Far North Coast which was recognised in 1996. (Full article...)
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Telopea truncata, commonly known as the Tasmanian waratah, is a plant in the family Proteaceae. It is endemic to Tasmania where it is found on moist acidic soils at altitudes of 600 to 1200 m (2000–4000 ft). Telopea truncata is a component of alpine eucalypt forest, rainforest and scrub communities. It grows as a multistemmed shrub to a height of 3 metres (10 ft), or occasionally as a small tree to 10 m (35 ft) high, with red flower heads, known as inflorescences, appearing over the Tasmanian summer (November to February) and bearing 10 to 35 individual flowers. Yellow-flowered forms are occasionally seen, but do not form a population distinct from the rest of the species.
Collected by French botanist Jacques Labillardière in 1792–93, Telopea truncata was first scientifically described in 1805. Genetic analysis revealed that the Tasmanian waratah is the most distinctive of the five waratah species. It can be cultivated in temperate climates, requiring soils with good drainage and ample moisture in part-shaded or sunny positions. Several commercially available cultivars that are hybrids of T. truncata with the New South Wales waratah (T. speciosissima) and Gippsland waratah (T. oreades) have been developed. (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...)
Banksia spinulosa, the hairpin banksia, is a species of woody shrub, of the genus Banksia in the family Proteaceae, native to eastern Australia. Widely distributed, it is found as an understorey plant in open dry forest or heathland from Victoria to northern Queensland, generally on sandstone though sometimes also clay soils. It generally grows as a small shrub to 2 metres (7 ft) in height, though can be a straggly tree to 6 metres (20 ft). It has long narrow leaves with inflorescences which can vary considerably in coloration; while the spikes are gold or less commonly yellowish, the emergent styles may be a wide range of colours – from black, purple, red, orange or yellow.
Banksia spinulosa was named by James Edward Smith in England in 1793, after being collected by John White, most likely in 1792. He gave it the common name prickly-leaved banksia, though this has fallen out of use. With four currently recognised varieties, the species has had a complicated taxonomic history, with two varieties initially described as separate species in the early 19th century. A fourth, from the New England region, has only recently been described. However, there has been disagreement whether one, var. cunninghamii, is distinct enough to once again have specific status. The pre-eminent authority on Banksia, Alex George, concedes there is still more work to be done on the Banksia spinulosa complex. (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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Banksia caleyi, commonly known as Caley's banksia or red lantern banksia, is a species of woody shrub of the family Proteaceae native to Western Australia. It generally grows as a dense shrub up to 2 m (7 ft) tall, has serrated leaves and red, pendent (hanging) inflorescences which are generally hidden in the foliage. First described by Scottish naturalist Robert Brown in 1830, Banksia caleyi was named in honour of the English botanist George Caley. No subspecies are recognised. It is one of three or four related species with hanging inflorescences, which is an unusual feature within the genus.
Adenanthos cuneatus, also known as coastal jugflower, flame bush, bridle bush and sweat bush, is a shrub of the family Proteaceae, native to the south coast of Western Australia. The French naturalist Jacques Labillardière originally described it in 1805. Within the genus Adenanthos, it lies in the sectionAdenanthos and is most closely related to A. stictus. A. cuneatus has hybridized with four other species of Adenanthos. Growing to 2 m (6 ft 7 in) high and wide, it is erect to prostrate in habit, with wedge-shaped lobed leaves covered in fine silvery hair. The single red flowers are insignificant, and appear all year, though especially in late spring. The reddish new growth occurs over the summer.
It is sensitive to Phytophthora cinnamomidieback, hence requiring a sandy soil and good drainage to grow in cultivation, its natural habitat of sandy soils in heathland being an example. Its pollinators include bees, honey possum, silvereye and honeyeaters, particularly the western spinebill. A. cuneatus is grown in gardens in Australia and the western United States, and a dwarf and prostrate form are commercially available. (Full article...)
Banksia sphaerocarpa, commonly known as the fox banksia or round-fruit banksia, is a species of shrub or tree in the plant genus Banksia (family Proteaceae). It is generally encountered as a 1–2 m (3.3–6.6 ft) high shrub, and is usually smaller in the north of its range. This species has narrow green leaves, and brownish, orange or yellow round flower spikes which may be seen from January to July. It is widely distributed across the southwest of Western Australia, growing exclusively in sandy soils. It is usually the dominant plant in scrubland or low woodland. It is pollinated by, and is a food source for, birds, mammals, and insects.
First described in 1810 by botanist Robert Brown, B. sphaerocarpa has a complicated taxonomic history, and several taxa once classified as part of a broadly defined B. sphaerocarpa have since been named as species in their own right. At present, most authorities recognise five varieties; the largest variety, B. sphaerocarpa var. dolichostyla (ironcap banksia), is sometimes given species rank as B. dolichostyla. B. sphaerocarpa is classified as Not Threatened under the Wildlife Conservation Act of Western Australia, although two varieties have been placed on the Declared Rare and Priority Flora List—var. latifolia has been designated a Priority Two – Poorly Known taxon, and var. dolichostyla falls under Declared Rare Flora. None of the varieties are commonly seen in cultivation. (Full article...)
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Several plants in cultivation
Drosera regia, commonly known as the king sundew, is a carnivorous plant in the sundew genus Drosera that is endemic to a single valley in South Africa. The genus name Drosera comes from the Greek word droseros, meaning "dew-covered". The specific epithetregia is derived from the Latin for "royal", a reference to the "striking appearance" of the species. Individual leaves can reach 70 cm (28 in) in length. It has many unusual relict characteristics not found in most other Drosera species, including woody rhizomes, operculatepollen, and the lack of circinate vernation in scape growth. All of these factors, combined with molecular data from phylogenetic analysis, contribute to the evidence that D. regia possesses some of the most ancient characteristics within the genus. Some of these are shared with the related Venus flytrap (Dionaea muscipula), which suggests a close evolutionary relationship.
The tentacle-covered leaves can capture large prey, such as beetles, moths, and butterflies. The tentacles of all Drosera species have special stalked glands on the leaf's upper surface that produce a sticky mucilage. The leaves are considered active flypaper traps that respond to captured prey by bending to surround it. In its native fynbos habitat, the plants compete for space with native marsh grasses and low evergreenshrubs. Of the two known populations of D. regia, the higher elevation site appears to be overgrown and is essentially extirpated. The lower elevation site is estimated to have about 50 mature plants, making it the most endangered Drosera species, since it is threatened with extinction in the wild. It is often cultivated by carnivorous plant enthusiasts, and a single cultivar has been registered. (Full article...)
Banksia coccinea, commonly known as the scarlet banksia, waratah banksia or Albany banksia, is an erect shrub or small tree in the familyProteaceae. Its distribution in the wild is along the south west coast of Western Australia, from Denmark to the Stokes National Park, and north to the Stirling Range, growing on white or grey sand in shrubland, heath or open woodland. Reaching up to 8 m (26 ft) in height, it is a single-stemmed plant that has oblong leaves, which are 3–9 cm (1.2–3.5 in) long and 2–7 cm (0.8–2.8 in) wide. The prominent red and white flower spikes appear mainly in the spring. As they age they develop small follicles that store seeds until opened by fire. Though widely occurring, it 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, Banksia coccinea appears to be most closely related to Banksia speciosa and B. baxteri. Banksia coccinea plants are killed by bushfire, and regenerate from seed. The flowers attract nectar- and insect-feeding birds, particularly honeyeaters, and a variety of insects. Widely considered one of the most attractive Banksia species, B. coccinea is a popular garden plant and one of the most important Banksia species for the cut flower industry; it is grown commercially in several countries including Australia, South Africa, Canada, the United States, New Zealand and Israel. In cultivation, B. coccinea grows well in a sunny location on well-drained soil, but it cannot survive in areas with humid or wet summers. (Full article...)
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Banksia scabrella, commonly known as the Burma Road banksia, is a species of woody shrub in the genus Banksia. It is classified in the series Abietinae, a group of several species of shrubs with small round or oval inflorescences. It occurs in a number of isolated populations south of Geraldton, Western Australia, with the largest population being south and east of Mount Adams. Found on sandy soils in heathland or shrubland, it grows to 2 m (7 ft) high and 3 m (10 ft) across with fine needle-like leaves. Appearing in spring and summer, the inflorescences are round to oval in shape and tan to cream with purple styles. Banksia scabrella is killed by fire and regenerates by seed.
Originally collected in 1966, B. scabrella was one of several species previously considered to be forms of Banksia sphaerocarpa, before it was finally described by banksia expert Alex George in his 1981 revision of the genus. Like many members of the Abietinae, it is rarely seen in cultivation; however, it has been described as having horticultural potential. (Full article...)
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Banksia lemanniana, the yellow lantern banksia or Lemann's banksia, is a species of flowering plant in the familyProteaceae, native to Western Australia. It generally grows as an open woody shrub or small tree to 5 m (16 ft) high, with stiff serrated leaves and unusual hanging inflorescences. Flowering occurs over summer, the greenish buds developing into oval flower spikes before turning grey and developing the characteristic large woody follicles. It occurs within and just east of the Fitzgerald River National Park on the southern coast of the state. B. lemanniana is killed by bushfire and regenerates from seed.
Described by Swiss botanist Carl Meissner in 1856, Banksia lemanniana was named in honour of English botanist Charles Morgan Lemann. It is one of three or four related species all with pendent inflorescences, which is an unusual feature of banksias. No subspecies are recognised. Banksia lemanniana is classified as Not Threatened under the Wildlife Conservation Act of Western Australia. Unlike many Western Australian banksias, it appears to have some resistance to dieback from the soil-borne water mouldPhytophthora cinnamomi, and is one of the easier Western Australian species to grow in cultivation. (Full article...)
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Persoonia linearis, commonly known as the narrow-leaved geebung, is a shrub native to New South Wales and Victoria in eastern Australia. It reaches 3 m (9.8 ft), or occasionally 5 m (16 ft), in height and has thick, dark grey papery bark. The leaves are, as the species name suggests, more or less linear in shape, and are up to 9 cm (3.5 in) long, and 0.1 to 0.7 cm (0.039 to 0.276 in) wide. The small yellow flowers appear in summer, autumn and early winter (December to July), followed by small green fleshy fruit known as drupes. Within the genus Persoonia, it is a member of the Lanceolata group of 58 closely related species. P. linearis interbreeds with several other species where they grow together.
Found in dry sclerophyll forest on sandstone-based nutrient-deficient soils, P. linearis is adapted to a fire-prone environment; the plants resprout epicormic buds from beneath their thick bark after bushfires. The fruit are consumed by vertebrates such as kangaroo, possums and currawongs. As with other members of the genus, P. linearis is rare in cultivation as it is very hard to propagate by seed or by cuttings, but once propagated, it adapts readily, preferring acidic soils with good drainage and at least a partly sunny aspect. (Full article...)
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Inflorescence
Banksia epica is a shrub that grows on the south coast of Western Australia. A spreading bush with wedge-shaped serrated leaves and large creamy-yellow flower spikes, it grows up to 3½ metres (11½ ft) high. It is known only from two isolated populations in the remote southeast of the state, near the western edge of the Great Australian Bight. Both populations occur among coastal heath on cliff-top dunes of siliceous sand.
One of the most recently described Banksia species, it was probably seen by Edward John Eyre in 1841, but was not collected until 1973, and was only recognised as a distinct species in 1988. There has been very little research on the species since then, so knowledge of its ecology and cultivation potential is limited. It is placed in Banksia ser. Cyrtostylis, alongside its close relative, the well-known and widely cultivated B. media (southern plains banksia). (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...)
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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...)
A banana is an elongated, edible fruit – botanically a berry – produced by several kinds of large herbaceousflowering plants in the genusMusa. In some countries, cooking bananas are called plantains, distinguishing them from dessert bananas. The fruit is variable in size, color, and firmness, but is usually elongated and curved, with soft flesh rich in starch covered with a rind, which may have a variety of colors when ripe. The fruits grow upward in clusters near the top of the plant. Almost all modern edible seedless (parthenocarp) bananas come from two wild species – Musa acuminata and Musa balbisiana. Most cultivated bananas are M. acuminata, M. balbisiana, or hybrids of the two.
Musa species are native to tropical Indomalaya and Australia; they were probably domesticated in New Guinea. They are grown in 135 countries, primarily for their fruit, and to a lesser extent to make banana paper and textiles, while some are grown as ornamental plants. The world's largest producers of bananas in 2022 were India and China, which together accounted for approximately 26% of total production. Bananas are eaten raw or cooked in recipes varying from curries to banana chips, fritters, fruit preserves, or simply baked or steamed. (Full article...)
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Utricularia vulgaris illustration from Jakob Sturm's "Deutschlands Flora in Abbildungen", Stuttgart (1796)
Utricularia, commonly and collectively called the bladderworts, is a genus of carnivorous plants consisting of approximately 233 species (precise counts differ based on classification opinions; a 2001 publication lists 215 species). They occur in fresh water and wet soil as terrestrial or aquatic species across every continent except Antarctica. Utricularia are cultivated for their flowers, which are often compared with those of snapdragons and orchids, especially amongst carnivorous plant enthusiasts.
All Utricularia are carnivorous and capture small organisms by means of bladder-like traps. Terrestrial species tend to have tiny traps that feed on minute prey such as protozoa and rotifers swimming in water-saturated soil. The traps can range in size from 0.02 to 1.2 cm (0.008 to 0.5 in). Aquatic species, such as U. vulgaris (common bladderwort), possess bladders that are usually larger and can feed on more substantial prey such as water fleas (Daphnia), nematodes and even fish fry, mosquitolarvae and young tadpoles. Despite their small size, the traps are extremely sophisticated. In the active traps of the aquatic species, prey brush against trigger hairs connected to the trapdoor. The bladder, when "set", is under negative pressure in relation to its environment so that when the trapdoor is mechanically triggered, the prey, along with the water surrounding it, is sucked into the bladder. Once the bladder is full of water, the door closes again, the whole process taking only ten to fifteen milliseconds. (Full article...)
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The Eastern Agricultural Complex in the woodlands of eastern North America was one of about 10 independent centers of plant domestication in the pre-historic world. Incipient agriculture dates back to about 5300 BCE. By about 1800 BCE the Native Americans of the woodlands were cultivating several species of food plants, thus beginning a transition from a hunter-gatherer economy to agriculture. After 200 BCE when maize from Mexico was introduced to the Eastern Woodlands, the Native Americans of the eastern United States and adjacent Canada slowly changed from growing local indigenous plants to a maize-based agricultural economy. The cultivation of local indigenous plants other than squash and sunflower declined and was eventually abandoned. The formerly domesticated plants returned to their wild forms.
In botany, a perennial plant or simply perennial is a plant that lives more than two years. The term (per- + -ennial, "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also widely used to distinguish plants with little or no woody growth (secondary growth in girth) from trees and shrubs, which are also technically perennials. Notably, it is estimated that 94% of plant species fall under the category of perennials, underscoring the prevalence of plants with lifespans exceeding two years in the botanical world.
Perennials—especially small flowering plants—that grow and bloom over the spring and summer, die back every autumn and winter, and then return in the spring from their rootstock or other overwintering structure, are known as herbaceous perennials. However, depending on the rigours of the local climate (temperature, moisture, organic content in the soil, microorganisms), a plant that is a perennial in its native habitat, or in a milder garden, may be treated by a gardener as an annual and planted out every year, from seed, from cuttings, or from divisions. Tomato vines, for example, live several years in their natural tropical/subtropical habitat but are grown as annuals in temperate regions because their above-ground biomass does not survive the winter. (Full article...)
Date palms reach up to 30 metres (100 feet) in height, growing singly or forming a clump with several stems from a single root system. Slow-growing, they can reach over 100years of age when maintained properly. Date fruits (dates) are oval-cylindrical, 3 to 7 centimetres (1 to 3 inches) long, and about 2.5 cm (1 in) in diameter, with colour ranging from dark brown to bright red or yellow, depending on variety. Containing 61–68percent sugar by mass when dried, dates are very sweet and are enjoyed as desserts on their own or within confections. (Full article...)
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Plant nutrition is the study of the chemical elements and compounds necessary for plant growth and reproduction, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element is part of some essential plant constituent or metabolite. This is in accordance with Justus von Liebig'slaw of the minimum. The total essential plant nutrients include seventeen different elements: carbon, oxygen and hydrogen which are absorbed from the air, whereas other nutrients including nitrogen are typically obtained from the soil (exceptions include some parasitic or carnivorous plants).
Plants must obtain the following mineral nutrients from their growing medium:
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. With worldwide research into pharmacology, some herbal medicines have been translated into modern remedies, such as the anti-malarial group of drugs called artemisinin isolated from Artemisia annua, a herb that was known in Chinese medicine to treat fever. There is limited scientific evidence for the safety and efficacy of many plants used in 21st-century herbalism, which generally does not provide standards for purity or dosage. The scope of herbal medicine sometimes include fungal and bee products, as well as minerals, shells and certain animal parts.
Paraherbalism describes alternative and pseudoscientific practices of using unrefined plant or animal extracts as unproven medicines or health-promoting agents. Paraherbalism relies on the belief that preserving various substances from a given source with less processing is safer or more effective than manufactured products, a concept for which there is no evidence. (Full article...)
Prunus is a genus of trees and shrubs in the flowering plant family Rosaceae that includes plums, cherries, peaches, nectarines, apricots, and almonds. The genus has a cosmopolitan distribution, being native to the North American temperate regions, the neotropics of South America, and temperate and tropical regions of Asia and Africa, There are 340 accepted species. Many members of the genus are widely cultivated for their fruit and for decorative purposes. Prunus fruit are drupes, or stone fruits. The fleshy mesocarp surrounding the endocarp is edible while the endocarp itself forms a hard, inedible shell called the pyrena ("stone" or "pit"). This shell encloses the seed (or "kernel"), which is edible in some species (such as sweet almonds), but poisonous in many others (such as apricots). Besides being eaten off the hand, most Prunus fruit are also commonly used in processing, such as jam production, canning, drying, and the seeds for roasting. (Full article...)
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...)
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Ethylene signaling pathway is a signal transduction in plant cells to regulate important growth and developmental processes. Acting as a plant hormone, the gas ethylene is responsible for promoting the germination of seeds, ripening of fruits, the opening of flowers, the abscission (or shedding) of leaves and stress responses. It is the simplest alkene gas and the first gaseous molecule discovered to function as a hormone.
Most of the understanding on ethylene signal transduction come from studies on Arabidopsis thaliana. Ethylene can bind to at least five different membrane receptors. Although structurally diverse, the ethylene receptors all exhibit similarity (homology) to two-component regulatory system in bacteria, indicating their common ancestry from bacterial ancestor. Ethylene binds to the receptors on the cell membrane of the endoplasmic reticulum. Although homodimers of the receptors are required for functional state, only one ethylene molecule binds to each dimer. (Full article...)
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Zosterophyllum species fossils; left: with coiled (circinate) branch tips, right: with sporangium
The zosterophylls are a group of extinct land plants that first appeared in the Silurian period. The taxon was first established by Banks in 1968 as the subdivisionZosterophyllophytina; they have since also been treated as the divisionZosterophyllophyta or Zosterophyta and the class or plesionZosterophyllopsida or Zosteropsida. They were among the first vascular plants in the fossil record, and had a world-wide distribution. They were probably stem-grouplycophytes, forming a sister group to the ancestors of the living lycophytes. By the late Silurian (late Ludlovian, about 420 million years ago) a diverse assemblage of species existed, examples of which have been found fossilised in what is now Bathurst Island in ArcticCanada. (Full article...)
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Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that grows in or near water and is either emergent, submergent, or floating. In lakes and rivers macrophytes provide cover for fish, substrate for aquaticinvertebrates, produce oxygen, and act as food for some fish and wildlife.
Macrophytes are primary producers and are the basis of the food web for many organisms. They have a significant effect on soil chemistry and light levels as they slow down the flow of water and capture pollutants and trap sediments. Excess sediment will settle into the benthos aided by the reduction of flow rates caused by the presence of plant stems, leaves and roots. Some plants have the capability of absorbing pollutants into their tissue. Seaweeds are multicellular marinealgae and, although their ecological impact is similar to other larger water plants, they are not typically referred to as macrophytes. (Full article...)
Cirsium vulgare is a species of thistle in the plant family Asteraceae. Native to Europe and Western Asia, it has become naturalised in North America, Africa and Australia, and is an invasive weed in some areas. It is a ruderal species, able to colonise bare ground, but also persists well on pasture as its thorny leaves and stems make it unpalatable to most grazing animals. The flowers are rich in nectar, attracting bees and butterflies, and the seeds are a favourite with goldfinches, linnets and greenfinches. The downy pappus, which assists in wind dispersal of the seeds, is used by birds as nest-lining material.
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 attractive for decorative purposes, and succeeds indoors as a potted plant. (Full article...)
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Cabbage tree on farmland, South Island, New Zealand
Cordyline australis, commonly known as the cabbage tree, or by its Māori name of tī or tī kōuka, is a widely branched monocot tree endemic to New Zealand.
It grows up to 20 metres (66 feet) tall with a stout trunk and sword-like leaves, which are clustered at the tips of the branches and can be up to 1 metre (3 feet 3 inches) long. With its tall, straight trunk and dense, rounded heads, it is a characteristic feature of the New Zealand landscape. Its fruit is a favourite food source for the kererū and other native birds. It is common over a wide latitudinal range from the far north of the North Island at 34° 25′S to the south of the South Island at 46° 30′S. Absent from much of Fiordland, it was probably introduced by Māori to the Chatham Islands at 44° 00′S and to Stewart Island / Rakiura at 46° 50′S. It grows in a broad range of habitats, including forest margins, river banks and open places, and is abundant near swamps. The largest known tree with a single trunk is growing at Pākawau, Golden Bay / Mohua. It is estimated to be 400 or 500 years old, and stands 17 metres (56 feet) tall with a circumference of 9 metres (30 feet) at the base. (Full article...)
Narcissus is a genus of predominantly spring flowering perennial plants of the amaryllis family, Amaryllidaceae. Various common names including daffodil, narcissus and jonquil, are used to describe all or some members of the genus. Narcissus has conspicuous flowers with six petal-like tepals surmounted by a cup- or trumpet-shaped corona. The flowers are generally white and yellow (also orange or pink in garden varieties), with either uniform or contrasting coloured tepals and corona.
Narcissi were well known in ancient civilisation, both medicinally and botanically, but were formally described by Linnaeus in his Species Plantarum (1753). The genus is generally considered to have about ten sections with approximately 36 species. The number of species has varied, depending on how they are classified, due to similarity between species and hybridisation. The genus arose some time in the Late Oligocene to Early Miocene epochs, in the Iberian peninsula and adjacent areas of southwest Europe. The exact origin of the name Narcissus is unknown, but it is often linked to a Greek word (ancient Greek ναρκῶ narkō, "to make numb") and the myth of the youth of that name who fell in love with his own reflection. The English word "daffodil" appears to be derived from "asphodel", with which it was commonly compared. (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 4 m (2.0 to 13.1 ft). 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...)
The leaflets of the plant are obovate-oblong and equal-sided, and of a silky texture. The fruits (legumes) are typically 1 to 2 in (25 to 51 mm) long and contain six or seven brownish seeds. The species typically grows in areas where the soils are relatively deep, especially in semi-arid and wadi areas, and on terraces and slight inclines and hills. (Full article...)
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Human uses of plants include both practical uses, such as for food, clothing, and medicine, and symbolic uses, such as in art, mythology and literature. The reliable provision of food through agriculture is the basis of civilization. The study of plant uses by native peoples is ethnobotany, while economic botany focuses on modern cultivated plants. Plants are used in medicine, providing many drugs from the earliest times to the present, and as the feedstock for many industrial products including timber and paper as well as a wide range of chemicals. Plants give millions of people pleasure through gardening.
Durio graveolens, sometimes called the red-fleshed durian, orange-fleshed durian, or yellow durian, is a species of tree in the family Malvaceae. It is one of six species of durian named by Italian naturalist Odoardo Beccari. The specific epithetgraveolens ('strong smelling' or 'rank') is due to the odor. Although most species of Durio (most notably Durio dulcis) have a strong scent, the red-fleshed type of D. graveolens has a mild scent. It is native to Southeast Asia.
D. graveolens is an edible durian, perhaps the most popular 'wild' species of durian, and it is sold commercially regionally. However, its congenerDurio zibethinus is the typical species eaten and dominates sales worldwide. (Full article...)
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Asplenium montanum, commonly known as the mountain spleenwort, is a small fern endemic to the eastern United States. It is found primarily in the Appalachian Mountains from Vermont to Alabama, with a few isolated populations in the Ozarks and in the Ohio Valley. It grows in small crevices in sandstone cliffs with highly acid soil, where it is usually the only vascular plant occupying that ecological niche. It can be recognized by its tufts of dark blue-green, highly divided leaves. The species was first described in 1810 by the botanist Carl Ludwig Willdenow. No subspecies have been described, although a discolored and highly dissected form was reported from the Shawangunk Mountains in 1974. Asplenium montanum is a diploid member of the "Appalachian Asplenium complex," a group of spleenwort species and hybrids which have formed by reticulate evolution. Members of the complex descended from A. montanum are among the few other vascular plants that can tolerate its typical habitat. (Full article...)
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The history of botany examines the human effort to understand life on Earth by tracing the historical development of the discipline of botany—that part of natural science dealing with organisms traditionally treated as plants.
Rudimentary botanical science began with empirically based plant lore passed from generation to generation in the oral traditions of paleolithichunter-gatherers. The first writings that show human curiosity about plants themselves, rather than the uses that could be made of them, appear in ancient Greece and ancient India. In Ancient Greece, the teachings of Aristotle's student Theophrastus at the Lyceum in ancient Athens in about 350 BC are considered the starting point for Western botany. In ancient India, the Vṛkṣāyurveda, attributed to Parashara, is also considered one of the earliest texts to describe various branches of botany. (Full article...)
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 orange originated in a region encompassing Southern China, Northeast India, and Myanmar; the earliest mention of the sweet orange was in Chinese literature in 314 BC. Orange trees are widely grown for their sweet fruit. The fruit of the orange tree can be eaten fresh, or processed for its juice or fragrant peel. In 2022, 76 million tonnes of oranges were grown worldwide, with Brazil producing 22% of the total, followed by India and China. (Full article...)
Some authors prefer the term "protocarnivorous" because it implies that these plants are on the evolutionary path to true carnivory, whereas others oppose the term for the same reason. The same problem arises with "subcarnivorous". Donald Schnell, author of the book Carnivorous Plants of the United States and Canada, prefers the term "paracarnivorous" for a less rigid definition of carnivory that can include many of the possible carnivorous plants. (Full article...)
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Myco-heterotrophy (from Greek μύκης mykes, "fungus", ἕτερος heteros, "another", "different" and τροφή trophe, "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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Cylindropuntia imbricata, the cane cholla (walking stick cholla, tree cholla, or chainlink cactus), is a cactus found in the Southwestern United States and northern Mexico, including some cooler regions in comparison to many other cacti. It occurs primarily in the arid regions of the Southwestern United States in the states of Kansas, Oklahoma, Texas, New Mexico, Arizona, Colorado, and Nevada. It is often conspicuous because of its shrubby or even tree-like size, its silhouette, and its long-lasting yellowish fruits. (Full article...)
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Characteres generum plantarum (complete title Characteres generum plantarum, quas in Itinere ad Insulas Maris Australis, Collegerunt, Descripserunt, Delinearunt, annis MDCCLXXII-MDCCLXXV Joannes Reinoldus Forster et Georgius Forster, "Characteristics of the types of plants collected, described, and delineated during a voyage to islands of the South Seas, in the years 1772–1775 by Johann Reinhold Forster and Georg Forster") is a 1775/1776 book by Johann Reinhold Forster and Georg Forster about the botanical discoveries they made during the second voyage of James Cook.
The book contains 78 plates, the majority of which depict dissections of flowers at natural size. The book introduced 94 binomial names from 75 genera, of which 43 are still the accepted names today. Many plant genera were named after friends or patrons of the Forsters. The book was published in a folio and a quarto edition and translated into German in 1779. It is an important book as the earliest publication of names and descriptions of the native species of New Zealand. (Full article...)
... 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"?
Image 2Thale cress, Arabidopsis thaliana, the first plant to have its genome sequenced, remains the most important model organism. (from Botany)
Image 3Structure 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 4The Linnaean Garden of Linnaeus' residence in Uppsala, Sweden, was planted according to his Systema sexuale. (from Botany)
Image 12The 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 13A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (from Botany)
Image 17Micropropagation of transgenic plants (from Botany)
Image 18The evolution of syncarps. a: sporangia borne at tips of leaf b: Leaf curls up to protect sporangia c: leaf curls to form enclosed roll d: grouping of three rolls into a syncarp (from Evolutionary history of plants)
Image 19The food we eat comes directly or indirectly from plants such as rice. (from Botany)
Image 20A 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 27A 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 28The 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 29The 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 30This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
Image 31A botanist preparing a plant specimen for mounting in the herbarium (from Botany)
Image 32Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 33The branching pattern of megaphyll veins may indicate their origin as webbed, dichotomising branches. (from Evolutionary history of plants)
Image 361 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 37Structure of a plant cell (from Plant cell)