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...)
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Banksia canei inflorescence
Banksia canei, commonly known as the mountain banksia, is a species of shrub that is endemic to southeastern Australia. It is generally encountered as a many-branched shrub that grows up to 3m (10ft) high, with narrow leaves and the yellow inflorescences (flower spikes) appearing from late summer to early winter. The old flowers fall off the spikes and up to 150 finely furred follicles develop, which remain closed until burnt in a bushfire. Each follicle bears two winged seeds. Response to fire is poorly known, although it is thought to regenerate by seed. Birds such as the yellow-tufted honeyeater and various insects forage among the flower spikes. It is frost tolerant in cultivation, but copes less well with aridity or humidity and is often short-lived in gardens. One cultivar, Banksia 'Celia Rosser', was registered in 1978, but has subsequently vanished.
Although no subspecies are recognised, four topodemes (geographically isolated populations) have been described, as there is significant variation in the shape of both adult and juvenile leaves between populations. Although superficially resembling B. marginata, it is more closely related to another subalpine species, B. saxicola. (Full article...)
Two subspecies—P.t.terminalis and P.t.recurva—are recognised; both are found on well-drained acidic soils in sclerophyll forests, and P.t.terminalis is also found on granite outcrops. Although similar in appearance, they differ in leaf length and curvature. Both have a restricted range, with P.t.terminalis found in an area of under 100 square kilometres (39 square miles; 25,000 acres). (Full article...)
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Banksia petiolaris is a rare species of flowering plant in the familyProteaceaenative to Western Australia, where it is found in sandy soils in the south coastal regions from Munglinup east to Israelite Bay. It was first described by Victorian state botanistFerdinand von Mueller in 1864, and no subspecies are recognised. B. petiolaris is one of several closely related species that will all grow as prostrate shrubs, with horizontal stems and thick, leathery upright leaves. Those of this species can be viable for up to 13 years—the longest-lived of any flowering plant recorded. It bears yellow cylindrical flower spikes, known as inflorescences, up to 16cm (6+1⁄4in) high in spring. As the spikes age, they turn grey and develop up to 20 woody seed pods, known as follicles, each.
Insects such as bees, wasps and even ants can pollinate the flowers. B.petiolaris is nonlignotuberous, meaning it regenerates by seed after bushfire. B.petiolaris adapts readily to cultivation, growing in well-drained sandy soils in sunny locations. It is suitable for rockeries and as a groundcover. (Full article...)
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Banksia cuneata, commonly known as matchstick banksia or Quairading banksia, is an endangered species of flowering plant in the family Proteaceae. Endemic to southwestWestern Australia, it belongs to Banksia subg. Isostylis, a sub-genus of three closely related Banksia species with inflorescences or flower clusters that are dome-shaped heads rather than characteristic Banksia flower spikes. A shrub or small tree up to 5m (16ft) high, it has prickly foliage and pink and cream flowers. The common name Matchstick Banksia arises from the blooms in late bud, the individual buds of which resemble matchsticks. The species is pollinated by honeyeaters (Meliphagidae).
Although B.cuneata was first collected before 1880, it was not until 1981 that Australian botanist Alex George formally described and named the species. There are two genetically distinct population groups, but no recognised varieties. This Banksia is classified as endangered, surviving in fragments of remnant bushland in a region which has been 93% cleared for agriculture. As Banksia cuneata is killed by fire and regenerates from seed, it is highly sensitive to bushfire frequency—fires recurring within four years could wipe out populations of plants not yet mature enough to set seed. Banksia cuneata is rarely cultivated, and its prickly foliage limits its utility in the cut flower industry. (Full article...)
Banksia serrata, commonly known as the saw banksia, the old man banksia, the saw-tooth banksia or the red honeysuckle and as wiriyagan by the Cadigal people, is a species of woody shrub or tree of the genus Banksia, in the family Proteaceae. Native to the east coast of Australia, it is found from Queensland to Victoria with outlying populations on Tasmania and Flinders Island. Commonly growing as a gnarled tree up to 16m (50ft) in height, it can be much smaller in more exposed areas. This Banksia species has wrinkled grey bark, shiny dark green serrated leaves and large yellow or greyish-yellow flower spikes appearing over summer. The flower spikes, or inflorescences, turn grey as they age and pollinated flowers develop into large, grey, woody seed pods called follicles.
B. serrata is one of the four original Banksia species collected by Sir Joseph Banks in 1770, and one of four species published in 1782 as part of Carolus Linnaeus the Younger's original description of the genus. There are no recognised varieties, although it is closely related to Banksia aemula. Throughout its range, it grows exclusively in sandy soil, and is usually the dominant plant in scrubland or low woodland. B. serrata is pollinated by and provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months, and is an important source of food for honeyeaters. It is a common plant of parks and gardens. (Full article...)
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A field of iceberg lettuces in California
Lettuce (Lactuca sativa) is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of food, such as soups, sandwiches and wraps; it can also be grilled. One variety, celtuce (asparagus lettuce), is 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. , world production of lettuce and chicory was 27 million tonnes, 53percent of which came from China.
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...)
Ficus macrophylla, commonly known as the Moreton Bay fig or Australian banyan, is a large evergreen banyan tree of the Mulberry Family (Moraceae) native to eastern Australia, from the Wide Bay–Burnett region in the north to the Illawarra in New South Wales, as well as Lord Howe Island where the subspecies F. m. columnaris is a banyan form covering 2.5 acres (a hectare) or more of ground. Its common name is derived from Moreton Bay in Queensland, Australia. It is best known for its imposing buttress roots.
Ficus macrophylla is called a strangler fig because seed germination usually takes place in the canopy of a host tree, where the seedling lives as an epiphyte until its roots establish contact with the ground, when it enlarges and strangles its host, eventually becoming a freestanding tree by itself. Individuals may reach 60m (200ft) in height, with crown spreads as great as 250 feet (76 metres) being reported. Like all figs, it has an obligate mutualism with fig wasps; figs are pollinated only by fig wasps, and fig wasps can reproduce only in fig flowers. The wasp partner of the Moreton Bay Fig is Pleistodontes froggattii. Many species of birds, including pigeons, parrots, and various passerines, eat the fruit. (Full article...)
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Grevillea juniperina, commonly known as juniper- or juniper-leaf grevillea or prickly spider-flower, is a plant of the family Proteaceae native to eastern New South Wales and southeastern Queensland in Australia. Scottish botanist Robert Brown described the species in 1810, and seven subspecies are recognised. One subspecies, G. j. juniperina, is restricted to Western Sydney and environs and is threatened by loss of habitat and housing development.
A small, prickly-leaved shrub between 0.2–3m (0.66–9.84ft) high, G. juniperina generally grows on clay-based or alluvial soils in eucalyptwoodland. The flower heads, known as inflorescences, appear from winter to early summer and are red, orange or yellow. Birds visit and pollinate the flowers. Grevillea juniperina plants are killed by bushfire, regenerating afterwards from seed. Grevillea juniperina adapts readily to cultivation and has been important in horticulture as it is the parent of many popular garden hybrids. (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 6m (20ft) high and wide, though is usually half that size. In exposed heathlands and coastal areas, it is more often 1–2m (3.3–6.6ft).
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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Acacia pycnantha, most commonly known as the golden wattle, is a tree of the family Fabaceae. It grows to a height of 8 metres (26 feet) and has phyllodes (flattened leaf stalks) instead of true leaves. The profuse fragrant, golden flowers appear in late winter and spring, followed by long seed pods. Explorer Thomas Mitchell collected the type specimen, from which George Bentham wrote the species description in 1842. The species is native to southeastern Australia as an understorey plant in eucalyptus forest. Plants are cross-pollinated by several species of honeyeater and thornbill, which visit nectaries on the phyllodes and brush against flowers, transferring pollen between them.
A. pycnantha has become a weed in areas of Australia, as well as in Africa and Eurasia. Its bark produces more tannin than any other wattle species, resulting in its commercial cultivation for production of this compound. It has been widely grown as an ornamental garden plant and for cut flower production. A. pycnantha was made the official floral emblem of Australia in 1988, and has been featured on the country's postal stamps. (Full article...)
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The flora of Madagascar consists of more than 12,000 species of plants, as well as a poorly known number of fungi and algae. Around 83% of Madagascar's vascular plants are found only on the island. These endemics include five plant families, 85% of the over 900 orchid species, around 200 species of palms, and such emblematic species as the traveller's tree, six species of baobab and the Madagascar periwinkle. The high degree of endemism is due to Madagascar's long isolation following its separation from the African and Indian landmasses in the Mesozoic, 150–160 and 84–91million years ago, respectively. However, few plant lineages remain from the ancient Gondwanan flora; most extant plant groups immigrated via across-ocean dispersal well after continental break-up.
After its continental separation, Madagascar probably experienced a dry period, and tropical rainforest expanded only later in the Oligocene to Miocene when rainfall increased. Today, humid forests, including the lowland forests, are mainly found on the eastern plateau where abundant rainfall from the Indian Ocean is captured by an escarpment. A large part of the central highlands, in the sub-humid forests ecoregion, is today dominated by grasslands. They are widely seen as result of human landscape transformation but some may be more ancient. Grassland occurs in a mosaic with woodland and bushland, including tapia forest, and hard-leaved thickets on the high mountains. Dry forest and succulent woodland are found in the drier western part and grade into the unique spiny thicket in the southwest, where rainfall is lowest and the wet season shortest. Mangroves occur on the west coast, and a variety of wetland habitats with an adapted flora are found across the island. (Full article...)
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Telopea oreades, commonly known as the Gippsland-, mountain- or Victorian waratah, is a large shrub or small tree in the family Proteaceae. Native to southeastern Australia, it is found in wet sclerophyll forest and rainforest on rich acidic soils high in organic matter. No subspecies are recognised, though a northern isolated population hybridises extensively with the Braidwood waratah (T.mongaensis). Reaching a height of up to 19 metres (62 feet), T. oreades grows with a single trunk and erect habit. It has dark green leaves with prominent veins that are 11–28 centimetres (4.3–11in) long and 1.5–6cm (0.6–2.4in) wide. The red flower heads, known as inflorescences, appear in late spring. Each is composed of up to 60 individual flowers.
In the garden, T. oreades grows in soils with good drainage and ample moisture in part-shaded or sunny positions. Several commercially available cultivars that are hybrid forms with T.speciosissima have been developed, such as the 'Shady Lady' series. The timber is hard and has been used for making furniture and tool handles. (Full article...)
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Inflorescence with unopened buds (left), opened flowers (right)
Banksia marginata, commonly known as the silver banksia, is a species of tree or woody shrub in the plant genusBanksia found throughout much of southeastern Australia. It ranges from the Eyre Peninsula in South Australia to north of Armidale, New South Wales, and across Tasmania and the islands of Bass Strait. It grows in various habitats, including Eucalyptus forest, scrub, heathland and moorland. Banksia marginata varies widely in habit, ranging from a 20-centimetre (7.9in) shrub to a 12-metre (40ft) tree. The narrow leaves are linear and the yellow inflorescences (flower spikes) occur from late summer to early winter. The flower spikes fade to brown and then grey and develop woody follicles bearing the winged seeds. Originally described by Antonio José Cavanilles in 1800, further collections of B.marginata were designated as several separate species by Robert Brown in 1810. However, all were reclassified as a single species by George Bentham in 1870. No distinct subspecies have been recognised by Banksia expert Alex George, who nonetheless concedes that further work is needed.
Many species of bird, in particular honeyeaters, forage at the flower spikes, as do native and European honeybees. The response to bushfire varies. Some populations are serotinous: they are killed by fire and regenerate from large stores of seed which have been held in cones in the plant canopy and are released after a fire. Others regenerate from underground lignotubers or suckers from lateral roots. Although it has been used for timber, Banksia marginata is most commonly seen as a garden plant, with dwarf forms being commercially propagated and sold. (Full article...)
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Alloxylon flammeum, commonly known as the Queensland tree waratah or red silky oak, is a medium-sized tree of the family Proteaceae found in the Queensland tropical rain forests of northeastern Australia. It has shiny green elliptical leaves up to 18cm (7.1in) long, and prominent orange-red inflorescences that appear from August to October, followed by rectangular woody seed pods that ripen in February and March. Juvenile plants have large (up to 25cm (9.8in) long) deeply lobed pinnate leaves. Previously known as Oreocallis wickhamii, the initial specimen turned out to be a different species to the one cultivated and hence a new scientific name was required. Described formally by Peter Weston and Mike Crisp in 1991, A. flammeum was designated the type species of the genus Alloxylon. This genus contains the four species previously classified in Oreocallis that are found in Australasia.
Alloxylon flammeum is a canopy or emergent tree of the Mabi rainforest community of north Queensland. Its terminal tubular flowers indicate that the species is pollinated by birds. Readily adaptable to cultivation, Alloxylon flammeum prefers a site with good drainage and responds well to extra moisture and fertilisers low in phosphorus. It is listed nationally as vulnerable under the Australian Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) as most of its habitat has been cleared for agriculture and logging. (Full article...)
Banksia menziesii, commonly known as firewood banksia, is a species of flowering plant in the genus Banksia. It is a gnarled tree up to 10m (33ft) tall, or a lower spreading 1–3m (3.3–9.8ft) 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...)
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...)
Monocotyledons (/ˌmɒnəˌkɒtəˈliːdənz/), commonly referred to as monocots, (Lilianaesensu Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of the major groups into which the flowering plants have traditionally been divided; the rest of the flowering plants have two cotyledons and are classified as dicotyledons, or dicots.
Monocotyledons have almost always been recognized as a group, but with various taxonomic ranks and under several different names. The APG III system of 2009 recognises a clade called "monocots" but does not assign it to a taxonomic rank. (Full article...)
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The olive, botanical name Olea europaea, meaning 'European olive', is a species of small tree or shrub in the family Oleaceae, found traditionally in the Mediterranean Basin. When in shrub form, it is known as Olea europaea'Montra', dwarf olive, or little olive. The species is cultivated in all the countries of the Mediterranean, as well as in Australia, New Zealand, North and South America and South Africa. It is the type species for its genus, Olea. The tree and its fruit give their name to the Oleaceae plant family, which also includes species such as lilac, jasmine, forsythia, and the true ash tree.
The olive's fruit, also called an "olive", is of major agricultural importance in the Mediterranean region as the source of olive oil; it is one of the core ingredients in Middle Easternand Mediterranean cuisines. Thousands of cultivars of the olive tree are known. Olive cultivars may be used primarily for oil, eating, or both. Olives cultivated for consumption are generally referred to as "table olives". About 80% of all harvested olives are turned into oil, while about 20% are used as table olives. (Full article...)
Vitis (grapevine) is a genus of 81 accepted species of vining plants in the flowering plant family Vitaceae. The genus consists of species predominantly from the Northern Hemisphere. It is economically important as the source of grapes, both for direct consumption of the fruit and for fermentation to produce wine. The study and cultivation of grapevines is called viticulture.
Most cultivated Vitis varieties are wind-pollinated with hermaphroditic flowers containing both male and female reproductive structures, while wild species are dioecious. These flowers are grouped in bunches called inflorescences. In many species, such as Vitis vinifera, each successfully pollinated flower becomes a grape berry with the inflorescence turning into a cluster of grapes. While the flowers of the grapevines are usually very small, the berries are often large and brightly colored with sweet flavors that attract birds and other animals to disperse the seeds contained within the berries. (Full article...)
Eucalyptus (/ˌjuːkəˈlɪptəs/) is a genus of more than 700 species of flowering plants in the family Myrtaceae. Most species of Eucalyptus are trees, often mallees, and a few are shrubs. Along with several other genera in the tribe Eucalypteae, including Corymbia and Angophora, they are commonly known as eucalypts or "gum trees". Plants in the genus Eucalyptus have bark that is either smooth, fibrous, hard, or stringy, the leaves have oil glands, and the sepals and petals are fused to form a "cap" or operculum over the stamens. The fruit is a woody capsule commonly referred to as a "gumnut".
Most species of Eucalyptus are native to Australia, and every state and territory has representative species. About three-quarters of Australian forests are eucalypt forests. Many eucalypt species have adapted to wildfire, are able to resprout after fire, or have seeds that survive fire. (Full article...)
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A cotyledon (/ˌkɒtɪˈliːdən/; fromLatincotyledon; fromκοτυληδών (kotulēdṓn) "a cavity, small cup, any cup-shaped hollow", gen. κοτυληδόνος (kotulēdónos), fromκοτύλη (kotýlē)'cup, bowl') is a "seed leaf" - a significant part of the embryo within the seed of a plant, and is formally defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." Botanists use the number of cotyledons present as one characteristic to classify the flowering plants (angiosperms): species with one cotyledon are called monocotyledonous ("monocots"); plants with two embryonic leaves are termed dicotyledonous ("dicots").
In the case of dicot seedlings whose cotyledons are photosynthetic, the cotyledons are functionally similar to leaves. However, true leaves and cotyledons are developmentally distinct. Cotyledons form during embryogenesis, along with the root and shoot meristems, and are therefore present in the seed prior to germination. True leaves, however, form post-embryonically (i.e. after germination) from the shoot apical meristem, which generates subsequent aerial portions of the plant. (Full article...)
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James Cocker and Sons is a nursery business located in Aberdeen, Scotland. Founded in 1841(183years 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...)
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Various gymnosperms.
The gymnosperms (/ˈdʒɪmnəˌspɜːrmz,-noʊ-/ⓘJIM-nə-spurmz, -noh-; lit.'revealed seeds') are a group of seed-producing plants that includes conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. The term gymnosperm comes from the composite word in Greek: γυμνόσπερμος (γυμνός, gymnos, 'naked' and σπέρμα, sperma, 'seed'), literally meaning 'naked seeds'. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or on their own as in yew, Torreya, Ginkgo. Gymnosperm lifecycles involve alternation of generations. They have a dominant diploidsporophyte phase and a reduced haploidgametophyte phase which is dependent on the sporophytic phase. The term "gymnosperm" is often used in paleobotany to refer to (the paraphyletic group of) all non-angiosperm seed plants. In that case, to specify the modern monophyletic group of gymnosperms, the term Acrogymnospermae is sometimes used.
The gymnosperms and angiosperms together constitute the spermatophytes or seed plants. The spermatophytes are subdivided into five divisions, the angiosperms and four divisions of gymnosperms: the Cycadophyta, Ginkgophyta, Gnetophyta, and Pinophyta (also known as Coniferophyta). Newer classification place the gnetophytes among the conifers. Numerous extinct seed plant groups are recognised including those considered pteridosperms/seed ferns, as well other groups like the Bennettitales. (Full article...)
Vavilov's work was criticized by Trofim Lysenko, whose anti-Mendelian concepts of plant biology had won favor with Joseph Stalin. As a result, Vavilov was arrested and subsequently sentenced to death in July 1941. Although his sentence was commuted to twenty years' imprisonment, he died in prison in 1943. In 1955, his death sentence was retroactively pardoned under Nikita Khrushchev. By the late 1950s, his reputation was publicly rehabilitated, and he began to be hailed as a hero of Soviet science. (Full article...)
Plant milk is a plant beverage with a color resembling that of milk. Plant milks are non-dairy beverages made from a water-based plant extract for flavoring and aroma. Plant milks are consumed as alternatives to dairy milk, and may provide a creamy mouthfeel.
As of 2021, there are about 17 different types of plant milks; almond, oat, soy, coconut, and pea are the highest-selling worldwide. Production of plant-based milks, particularly soy, oat, and pea milks, can offer environmental advantages over animal milks in terms of greenhouse gas emissions, land and water use. (Full article...)
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Taraxacum (/təˈræksəkəm/) is a large 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 is native to Eurasia and North America, but the two most commonplace species worldwide, T.officinale (the common dandelion) and T.erythrospermum (the red-seeded dandelion), were introduced from Europe into North America, where they now propagate as wildflowers. The plant thrives in temperate regions and can be found in yards, gardens, sides of roads, among crops, and in many other habitats. Both species are edible in their entirety and have a long history of consumption. The common name dandelion (/ˈdændəlaɪ.ən/DAN-də-ly-ən; fromFrenchdent-de-lion'lion's tooth', referring to the jagged leaves) is also given to specific members of the genus.
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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Herbicides (US: /ˈɜːrbɪsaɪdz/, UK: /ˈhɜːr-/), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds. Selective herbicides control specific weed species while leaving the desired crop relatively unharmed, while non-selective herbicides (sometimes called "total weed killers") kill plants indiscriminately. The combined effects of herbicides, nitrogen fertilizer, and improved cultivars has increased yields (per acre) of major crops by 3x to 6x from 1900 to 2000.
In the United States in 2012, about 91% of all herbicide usage, determined by weight applied, was in agriculture. In 2012, world pesticide expenditures totaled nearly $24.7 billion; herbicides were about 44% of those sales and constituted the biggest portion, followed by insecticides, fungicides, and fumigants. Herbicide is also used in forestry, where certain formulations have been found to suppress hardwood varieties in favor of conifers after clearcutting, as well as pasture systems. (Full article...)
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Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anther of a flower to the stigma of the same flower.
Pollen is infrequently used as food and food supplement. Because of agricultural practices, it is often contaminated by agricultural pesticides. (Full article...)
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Pollination syndromes are suites of flower traits that have evolved in response to natural selection imposed by different pollen vectors, which can be abiotic (wind and water) or biotic, such as birds, bees, flies, and so forth through a process called pollinator-mediated selection.[pageneeded][pageneeded] These traits include flower shape, size, colour, odour, reward type and amount, nectar composition, timing of flowering, etc. For example, tubular red flowers with copious nectar often attract birds; foul smelling flowers attract carrion flies or beetles, etc.
The "classical" pollination syndromes were first studied in the 19th century by the Italian botanist Federico Delpino. Although they are useful in understanding of plant-pollinator interactions, sometimes the pollinator of a plant species cannot be accurately predicted from the pollination syndrome alone, and caution must be exerted in making assumptions. (Full article...)
Immature cones of a Colorado Blue Spruce (Picea pungens), a species of spruce native to western North America. It is a medium-sized evergreen tree growing to 25 to 30 metres (82 to 98ft) tall, exceptionally to 46m (151ft) tall, and with a trunk diameter of up to 1.5m (4.9ft). The cones are slender and cylindrical, 6–11 centimetres (2.4–4.3in) long, and are reddish to violet in color, maturing to pale brown 5–7 months after pollination. The Blue Spruce is the state tree of Utah and Colorado.
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The Mingo Oak (also known as the Mingo White Oak) was a white oak (Quercus alba) in the U.S. state of West Virginia. First recognized for its age and size in 1931, the Mingo Oak was the oldest and largest living white oak tree in the world until its death in 1938.
The Mingo Oak stood in Mingo County, West Virginia, in a cove at the base of Trace Mountain near the headwaters of the Trace Fork of Pigeon Creek, a tributary stream of Tug Fork. The tree reached a height of over 200 feet (61m), and its trunk was 145 feet (44m) in height. Its crown measured 130 feet (40m) in diameter and 60 feet (18m) in height. The tree's trunk measured 9feet 10inches (3.00m) in diameter and the circumference of its base measured 30feet 9inches (9.37m). Assessments of its potential board lumber ranged from 15,000 feet (4,600m) to 40,000 feet (12,000m). Following the tree's felling in 1938, it was estimated to weigh approximately 5,400 long tons (5,500t). (Full article...)
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Phragmipedium kovachii is an orchid species found to be new to science in 2001, native to the Andean cloud forests of northern Peru. A species with terrestrial habit and growing in clumps of several individuals, it displays showy pink to purple flowers up to 20cm (8in) wide. It is currently considered a critically endangered species by the IUCN, due to overcollection in the wild. (Full article...)
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The poinsettia (/pɔɪnˈsɛt(i)ə/; Euphorbia pulcherrima) is a commercially important flowering plant species of the diverse spurge family Euphorbiaceae. Indigenous to Mexico and Central America, the poinsettia was first described by Europeans in 1834. It is particularly well known for its red and green foliage and is widely used in Christmas floral displays. It derives its common English name from Joel Roberts Poinsett, the first United States minister to Mexico, who is credited with introducing the plant to the US in the 1820s. Poinsettias are shrubs or small trees, with heights of 0.6 to 4m (2.0 to 13.1ft). Though often stated to be highly toxic, the poinsettia is not dangerous to pets or children. Exposure to the plant, even consumption, most often results in no effect, though it can cause nausea, vomiting, or diarrhea.
Wild poinsettias occur from Mexico to southern Guatemala, growing on mid-elevation, Pacific-facing slopes. One population in the Mexican state of Guerrero is much further inland, however, and is thought to be the ancestor of most cultivated populations. Wild poinsettia populations are highly fragmented, as their habitat is experiencing largely unregulated deforestation. They were cultivated by the Aztecs for use in traditional medicine. They became associated with the Christmas holiday and are popular seasonal decorations. Every year in the United States, approximately 70 million poinsettias of many cultivated varieties are sold in a six-week period. Many of these poinsettias are grown by Paul Ecke Ranch, which serves half the worldwide market and 70 percent of the US market. (Full article...)
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Flower and fruit
Eucalyptus rhodantha, commonly known as rose mallee or rose gum, is a species of straggly mallee or shrub native to parts of Western Australia. It has smooth bark and a crown composed entirely of circular to heart-shaped juvenile leaves arranged in opposite pairs and attached directly to the stems with no stalks. The flower buds appear singly in the leaf axils and are red, the fruits hemispherical to conical and pendent. The rose mallee is grown as an ornamental shrub suitable for gardens in hot and dry climates. It is found more often in urban gardens and cultivation than in the wild and is readily available in seed form.
Augustin Pyramus (or Pyrame) de Candolle (UK: /kænˈdɒl/, US: /kɒ̃ˈdɔːl/, French:[kɑ̃dɔl]; 4 February 1778–9 September 1841) was a Swissbotanist. René Louiche Desfontaines launched de Candolle's botanical career by recommending him at a herbarium. Within a couple of years de Candolle had established a new genus, and he went on to document hundreds of plant families and create a new natural plant classification system. Although de Candolle's main focus was botany, he also contributed to related fields such as phytogeography, agronomy, paleontology, medical botany, and economic botany.
De Candolle originated the idea of "Nature's war", which influenced Charles Darwin and the principle of natural selection. de Candolle recognized that multiple species may develop similar characteristics that did not appear in a common evolutionary ancestor; a phenomenon now known as convergent evolution. During his work with plants, de Candolle noticed that plant leaf movements follow a near-24-hour cycle in constant light, suggesting that an internal biological clock exists. Though many scientists doubted de Candolle's findings, experiments over a century later demonstrated that "the internal biological clock" indeed exists. (Full article...)
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Various Cactaceae from Brockhaus' Konversations-Lexikon v. 2 1892
A cactus (pl.: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (/kæˈkteɪsiaɪ,-siːiː/), a family comprising about 127 genera with some 1,750 known species of the order Caryophyllales. The word cactus derives, through Latin, from the Ancient Greek word κάκτος (káktos), a name originally used by Theophrastus for a spiny plant whose identity is now not certain. Cacti occur in a wide range of shapes and sizes. They are native to the Americas, ranging from Patagonia in the south to parts of western Canada in the north, with the exception of Rhipsalis baccifera, which is also found in Africa and Sri Lanka. Cacti are adapted to live in very dry environments, including the Atacama Desert, one of the driest places on Earth. Because of this, cacti show many adaptations to conserve water. For example, almost all cacti are succulents, meaning they have thickened, fleshy parts adapted to store water. Unlike many other succulents, the stem is the only part of most cacti where this vital process takes place. Most species of cacti have lost true leaves, retaining only spines, which are highly modified leaves. As well as defending against herbivores, spines help prevent water loss by reducing air flow close to the cactus and providing some shade. In the absence of true leaves, cacti's enlarged stems carry out photosynthesis.
Cactus spines are produced from specialized structures called areoles, a kind of highly reduced branch. Areoles are an identifying feature of cacti. As well as spines, areoles give rise to flowers, which are usually tubular and multipetaled. Many cacti have short growing seasons and long dormancies and are able to react quickly to any rainfall, helped by an extensive but relatively shallow root system that quickly absorbs any water reaching the ground surface. Cactus stems are often ribbed or fluted with a number of ribs which corresponds to a number in the Fibonacci numbers (2, 3, 5, 8, 13, 21, 34 etc.). This allows them to expand and contract easily for quick water absorption after rain, followed by retention over long drought periods. Like other succulent plants, most cacti employ a special mechanism called "crassulacean acid metabolism" (CAM) as part of photosynthesis. Transpiration, during which carbon dioxide enters the plant and water escapes, does not take place during the day at the same time as photosynthesis, but instead occurs at night. The plant stores the carbon dioxide it takes in as malic acid, retaining it until daylight returns, and only then using it in photosynthesis. Because transpiration takes place during the cooler, more humid night hours, water loss is significantly reduced. (Full article...)
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Eriophorum angustifolium, commonly known as common cottongrass or common cottonsedge, is a species of flowering plant in the sedge family, Cyperaceae. Native to North America, North Asia, and Europe, it grows on peat or acidic soils, in open wetland, heath or moorland. It begins to flower in April or May and, after fertilisation in early summer, the small, unremarkable brown and green flowers develop distinctive white bristle-like seed-heads that resemble tufts of cotton; combined with its ecological suitability to bog, these characteristics give rise to the plant's alternative name, bog cotton.
Eriophorum angustifolium is a hardy, herbaceous, rhizomatous, perennial sedge, able to endure in a variety of environments in the temperate, subarctic and arctic regions of Earth. Unlike Gossypium, the genus from which cotton is derived, the bristles which grow on E.angustifolium are unsuited to textile manufacturing. Nevertheless, in Northern Europe, they were used as a substitute in the production of paper, pillows, candle-wicks, and wound-dressings. The indigenous peoples of North America use the plant in cooking and in the treatment of digestive problems. Following a vote in 2002, Plantlife International designated E.angustifolium the County Flower of Greater Manchester, as part of its British County Flowers campaign. (Full article...)
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Cowpeas
The cowpea (Vigna unguiculata) is an annualherbaceouslegume from the genus Vigna. Its tolerance for sandy soil and low rainfall have made it an important crop in the semiarid regions across Africa and Asia. It requires very few inputs, as the plant's root nodules are able to fix atmospheric nitrogen, making it a valuable crop for resource-poor farmers and well-suited to intercropping with other crops. The whole plant is used as forage for animals, with its use as cattle feed likely responsible for its name.
Four subspecies of cowpeas are recognised, of which three are cultivated. A high level of morphological diversity is found within the species with large variations in the size, shape, and structure of the plant. Cowpeas can be erect, semierect (trailing), or climbing. The crop is mainly grown for its seeds, which are high in protein, although the leaves and immature seed pods can also be consumed. (Full article...)
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An engraving of Parkinson from his monumental work Theatrum Botanicum (1640), reprinted in Agnes Arber's Herbals (1912).
John Parkinson (1567–1650; buried 6 August 1650) was the last of the great English herbalists and one of the first of the great English botanists. He was apothecary to James I and a founding member of the Worshipful Society of Apothecaries in December 1617, and was later Royal Botanist to Charles I. He is known for two monumental works, Paradisi in Sole Paradisus Terrestris (Park-in-Sun's Terrestrial Paradise, 1629), which generally describes the proper cultivation of plants; and Theatrum Botanicum (The Botanical Theatre or Theatre of Plants, 1640), the most complete and beautifully presented English treatise on plants of its time. One of the most eminent gardeners of his day, he kept a botanical garden at Long Acre in Covent Garden, today close to Trafalgar Square, and maintained close relations with other important English and Continental botanists, herbalists and plantsmen. (Full article...)
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A mature Asplenium bradleyi growing in a crevice in schist
Asplenium bradleyi, commonly known as Bradley's spleenwort or cliff spleenwort, is a rare epipetricfern of east-central North America. Named after Professor Frank Howe Bradley, who first collected it in Tennessee, it may be found infrequently throughout much of the Appalachian Mountains, the Ozarks, and the Ouachita Mountains, growing in small crevices on exposed sandstone cliffs. The species originated as a hybrid between mountain spleenwort (Asplenium montanum) and ebony spleenwort (Asplenium platyneuron); A.bradleyi originated when that sterile diploid hybrid underwent chromosome doubling to become a fertile tetraploid, a phenomenon known as allopolyploidy. Studies indicate that the present population of Bradley's spleenwort arose from several independent doublings of sterile diploid hybrids. A.bradleyi can also form sterile hybrids with several other spleenworts.
While A.bradleyi is easily outcompeted by other plants in more fertile habitats, it is well adapted to the thin, acidic soil and harsh environment of its native cliffs, where it finds few competitors. Its isolated situation on these cliffs protects it from most threats, but quarrying and mining of the cliffs, rock climbing, and other activities that disturb the cliff ecosystem can destroy it. (Full article...)
An evergreenperennial, it originates from the Arabian Peninsula, but also grows wild in tropical, semi-tropical, and arid climates around the world. It is cultivated for commercial products, mainly as a topical treatment used over centuries. The species is attractive for decorative purposes, and succeeds indoors as a potted plant. (Full article...)
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c.1680Portrait of a Mathematician by Mary Beale, conjectured to be of Hooke but also conjectured to be of Isaac Barrow
Robert HookeFRS (/hʊk/; 18 July 1635–3 March 1703) was an English polymath who was active as a physicist ("natural philosopher"), astronomer, geologist, meteorologist and architect. He is credited as one of the first scientists to investigate living things at microscopic scale in 1665, using a compound microscope that he designed. Hooke was an impoverished scientific inquirer in young adulthood who went on to became one of the most important scientists of his time. After the Great Fire of London in 1666, Hooke (as a surveyor and architect) attained wealth and esteem by performing more than half of the property line surveys and assisting with the city's rapid reconstruction. Often vilified by writers in the centuries after his death, his reputation was restored at the end of the twentieth century and he has been called "England's Leonardo [da Vinci]".
Hooke was a Fellow of the Royal Society and from 1662, he was its first Curator of Experiments. From 1665 to 1703, he was also Professor of Geometry at Gresham College. Hooke began his scientific career as an assistant to the physical scientist Robert Boyle. Hooke built the vacuum pumps that were used in Boyle's experiments on gas law and also conducted experiments. In 1664, Hooke identified the rotations of Mars and Jupiter. Hooke's 1665 book Micrographia, in which he coined the term cell, encouraged microscopic investigations. Investigating optics– specifically light refraction– Hooke inferred a wave theory of light. His is the first-recorded hypothesis of the cause of the expansion of matter by heat, of air's composition by small particles in constant motion that thus generate its pressure, and of heat as energy. (Full article...)
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Artist's reconstruction of Archaeamphora longicervia after Li (2005)
The species was originally described as a pitcher plant with close affinities to extant members of the familySarraceniaceae. This would make it the earliest known carnivorous plant and the only known fossil record of Sarraceniaceae, or the New World pitcher plant family. Archaeamphora is also one of the three oldest known genera of angiosperms (flowering plants). Li (2005) wrote that "the existence of a so highly derived Angiosperm in the Early Cretaceous suggests that Angiosperms should have originated much earlier, maybe back to 280 mya as the molecular clock studies suggested". (Full article...)
Symphyotrichum novae-angliae (formerly Aster novae-angliae) is a species of flowering plant in the aster family (Asteraceae) native to central and eastern North America. Commonly known as New England aster, hairy Michaelmas-daisy, or Michaelmas daisy, it is a perennial, herbaceous plant usually between 30 and 120 centimeters (1 and 4 feet) tall and 60 to 90cm (2 to 3ft) wide.
The usually deep purple flowers have up to 100 ray florets which are rarely pink or white. These surround the flower centers which are composed of just as many tiny yellow disk florets. The plant grows naturally in clumps, with several erect stems emerging from a single point. The stems are stout, hairy, and mostly unbranched. The untoothed, lance-shaped leaves clasp the stem with earlobe-like appendages, and the lower stem leaves often wither by the time of flowering. (Full article...)
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Clusters of Bidni olives ripening on the tree
The Bidni, which is also referred to as Bitni, is an olive cultivar from the Mediterranean island of Malta. The fruit is small in size, hearty with a "violet colour", and is renowned for its superior oil which is low in acidity. The latter is generally attributed to the poor quality alkaline soil found on the Maltese Islands. As an indigenous olive cultivar, the Bidni has developed a unique DNA profile, and is believed to be among the most ancient species on the island, triggering local authorities to declare some of these ancient trees as "national monuments", and as having an "Antiquarian Importance", a status which is enjoyed by only a handful of other species. (Full article...)
... 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 plant biology professor Luca Comai independently developed glyphosate-resistant plants while working at Calgene and published his research before Monsanto researchers were able to?
... that according to Lois N. Magner, Hildegard of Bingen's Physica is "probably the first book by a female author to discuss the elements and the therapeutic virtues of plants, animals, and metals"?
The following are images from various plant-related articles on Wikipedia.
Image 1A banded tube from the Late Silurian/Early Devonian. The bands are difficult to see on this specimen, as an opaque carbonaceous coating conceals much of the tube. Bands are just visible in places on the left half of the image. Scale bar: 20μm (from Evolutionary history of plants)
Image 2This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
Image 3A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (from Botany)
Image 4Transverse section of a fossil stem of the Devonian vascular plant Rhynia gwynne-vaughani (from Botany)
Image 8Five of the key areas of study within plant physiology (from Botany)
Image 9The branching pattern of megaphyll veins may indicate their origin as webbed, dichotomising branches. (from Evolutionary history of plants)
Image 10The 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 11Structure 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 121 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 13The Linnaean Garden of Linnaeus' residence in Uppsala, Sweden, was planted according to his Systema sexuale. (from Botany)
Image 14Leaf lamina. The megaphyllous leaf architecture arose multiple times in different plant lineages (from Evolutionary history of plants)
Image 25The 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 30The 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 32The 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 34Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)