1.
Crassula ovata
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Crassula ovata, commonly known as jade plant, friendship tree, lucky plant, or money tree, is a succulent plant with small pink or white flowers. It is native to South Africa and Mozambique, and is common as a houseplant worldwide, much of its popularity stems from the low levels of care needed, the jade plant requires little water and can survive in most indoor conditions. It is sometimes referred to as the tree, however. The jade plant is an evergreen with thick branches and it has thick, shiny, smooth, leaves that grow in opposing pairs along the branches. Leaves are a rich green, although some may appear to be more of a yellow-green. Some varieties may develop a red tinge on the edges of leaves when exposed to levels of sunlight. New stem growth is the color and texture as the leaves. Although becoming brown and appearing woody with age, stems never become true lignified tissue, remaining succulent, under the right conditions, they may produce small white or pink star-like flowers in early spring. Numerous varieties and cultivars have been selected, of which C. ovata Hummels Sunset has gained the Royal Horticultural Societys Award of Garden Merit, Crassula ovata is native to Mozambique and to the Eastern Cape and KwaZulu-Natal provinces of South Africa. As a succulent, Crassula ovata requires little water in the summer, C. ovata may garnish a red tinge around its leaves when grown with bright sunlight. In more extreme cases, the colour of the plant is lost. This is caused by the plant making pigments such as carotenoids to protect from harsh sunlight. The jade plant also does best in rich, well-draining soil, the plant also flowers in the wintertime, particularly during a cooler, darker, dry spell. C. ovata is sometimes attacked by mealybugs, a nuisance of the succulents. The jade plant is known for its ease of propagation. Jade plants propagate readily from both with success rates higher with cuttings, in the wild, propagation is the jade plants main method of reproduction. Branches regularly fall off wild jade plants and these branches may root, like many succulents, jade plants can be propagated from just the swollen leaves which grow in pairs on the stems. While propagation methods may vary, most will follow similar steps, typically, the wounds on the leaves are left to dry and callous over
2.
Taxonomy (biology)
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Taxonomy is the science of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups. The exact definition of taxonomy varies from source to source, but the core of the remains, the conception, naming. There is some disagreement as to whether biological nomenclature is considered a part of taxonomy, the broadest meaning of taxonomy is used here. The word taxonomy was introduced in 1813 by Candolle, in his Théorie élémentaire de la botanique, the term alpha taxonomy is primarily used today to refer to the discipline of finding, describing, and naming taxa, particularly species. In earlier literature, the term had a different meaning, referring to morphological taxonomy, ideals can, it may be said, never be completely realized. They have, however, a value of acting as permanent stimulants. Some of us please ourselves by thinking we are now groping in a beta taxonomy, turrill thus explicitly excludes from alpha taxonomy various areas of study that he includes within taxonomy as a whole, such as ecology, physiology, genetics, and cytology. He further excludes phylogenetic reconstruction from alpha taxonomy, thus, Ernst Mayr in 1968 defined beta taxonomy as the classification of ranks higher than species. This activity is what the term denotes, it is also referred to as beta taxonomy. How species should be defined in a group of organisms gives rise to practical and theoretical problems that are referred to as the species problem. The scientific work of deciding how to define species has been called microtaxonomy, by extension, macrotaxonomy is the study of groups at higher taxonomic ranks, from subgenus and above only, than species. While some descriptions of taxonomic history attempt to date taxonomy to ancient civilizations, earlier works were primarily descriptive, and focused on plants that were useful in agriculture or medicine. There are a number of stages in scientific thinking. Early taxonomy was based on criteria, the so-called artificial systems. Later came systems based on a complete consideration of the characteristics of taxa, referred to as natural systems, such as those of de Jussieu, de Candolle and Bentham. The publication of Charles Darwins Origin of Species led to new ways of thinking about classification based on evolutionary relationships and this was the concept of phyletic systems, from 1883 onwards. This approach was typified by those of Eichler and Engler, the advent of molecular genetics and statistical methodology allowed the creation of the modern era of phylogenetic systems based on cladistics, rather than morphology alone. Taxonomy has been called the worlds oldest profession, and naming and classifying our surroundings has likely been taking place as long as mankind has been able to communicate
3.
Plant
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Plants are mainly multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. The term is generally limited to the green plants, which form an unranked clade Viridiplantae. This includes the plants, conifers and other gymnosperms, ferns, clubmosses, hornworts, liverworts, mosses and the green algae. Green plants have cell walls containing cellulose and obtain most of their energy from sunlight via photosynthesis by primary chloroplasts and their chloroplasts contain chlorophylls a and b, which gives them their green color. Some plants are parasitic and have lost the ability to produce amounts of chlorophyll or to photosynthesize. Plants are characterized by sexual reproduction and alternation of generations, although reproduction is also common. There are about 300–315 thousand species of plants, of which the great majority, green plants provide most of the worlds molecular oxygen and are the basis of most of Earths ecologies, especially on land. Plants that produce grains, fruits and vegetables form humankinds basic foodstuffs, Plants play many roles in culture. They are used as ornaments and, until recently and in variety, they have served as the source of most medicines. The scientific study of plants is known as botany, a branch of biology, Plants are one of the two groups into which all living things were traditionally divided, the other is animals. The division goes back at least as far as Aristotle, who distinguished between plants, which generally do not move, and animals, which often are mobile to catch their food. Much later, when Linnaeus created the basis of the system of scientific classification. Since then, it has become clear that the plant kingdom as originally defined included several unrelated groups, however, these organisms are still often considered plants, particularly in popular contexts. When the name Plantae or plant is applied to a group of organisms or taxon. The evolutionary history of plants is not yet settled. Those which have been called plants are in bold, the way in which the groups of green algae are combined and named varies considerably between authors. Algae comprise several different groups of organisms which produce energy through photosynthesis, most conspicuous among the algae are the seaweeds, multicellular algae that may roughly resemble land plants, but are classified among the brown, red and green algae. Each of these groups also includes various microscopic and single-celled organisms
4.
Flowering plant
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The flowering plants, also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with 416 families, approx. 13,164 known genera and a total of c.295,383 known species, etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant. The term angiosperm comes from the Greek composite word meaning enclosed seeds, the ancestors of flowering plants diverged from gymnosperms in the Triassic Period, during the range 245 to 202 million years ago, and the first flowering plants are known from 160 mya. They diversified extensively during the Lower Cretaceous, became widespread by 120 mya, angiosperms differ from other seed plants in several ways, described in the table. These distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants, the amount and complexity of tissue-formation in flowering plants exceeds that of gymnosperms. The vascular bundles of the stem are arranged such that the xylem and phloem form concentric rings, in the dicotyledons, the bundles in the very young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue known as cambium, the soft phloem becomes crushed, but the hard wood persists and forms the bulk of the stem and branches of the woody perennial. Among the monocotyledons, the bundles are more numerous in the stem and are scattered through the ground tissue. They contain no cambium and once formed the stem increases in diameter only in exceptional cases, the characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, and provide the most trustworthy external characteristics for establishing relationships among angiosperm species, the function of the flower is to ensure fertilization of the ovule and development of fruit containing seeds. The floral apparatus may arise terminally on a shoot or from the axil of a leaf, occasionally, as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. There are two kinds of cells produced by flowers. Microspores, which divide to become pollen grains, are the male cells and are borne in the stamens. The female cells called megaspores, which divide to become the egg cell, are contained in the ovule. The flower may consist only of parts, as in willow. Usually, other structures are present and serve to protect the sporophylls, the individual members of these surrounding structures are known as sepals and petals. The outer series is usually green and leaf-like, and functions to protect the rest of the flower, the inner series is, in general, white or brightly colored, and is more delicate in structure. It functions to attract insect or bird pollinators, attraction is effected by color, scent, and nectar, which may be secreted in some part of the flower
5.
Echeveria
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Echeveria is a large genus of flowering plants in the Crassulaceae family, native to semi-desert areas of Central America, Mexico and northwestern South America. Plants may be evergreen or deciduous, flowers on short stalks arise from compact rosettes of succulent fleshy, often brightly coloured leaves. Species are polycarpic, meaning that they may flower and set seed many times over the course of their lifetimes. Often numerous offsets are produced, and are known as hen and chicks, which can also refer to other genera, such as Sempervivum. The genus is named after the 18th century Mexican botanical artist Atanasio Echeverría y Godoy, many Echeveria species are popular as ornamental garden plants. They are drought-resistant, although they do better with regular watering and fertilizing. Most will tolerate shade and some frost, although tend to be less tolerant. Most lose their leaves in winter, as a result, after a few years. In addition, if not removed, the leaves may decay. They can be propagated easily by separating offsets, but also by leaf cuttings, Echeveria has been extensively bred and hybridised. The following is a selection of available plants, perle von Nürnberg has gained the Royal Horticultural Societys Award of Garden Merit
6.
Hen and chicks
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Hen and chicks is a common name for a group of small succulent plants belonging to the flowering plant family Crassulaceae, native to southern Europe and northern Africa. They grow close to the ground with leaves formed around each other in a rosette, and propagating by offsets. The hen is the plant, and the chicks are the offspring. The name is used for some species of Echeveria, Sedum and Bergenia although these plants differ significantly from Sempervivum and Jovibarba. Hen and chicks is popular in gardens for its varied and interesting appearance and it is grown as container planting or in rock gardens. It does best in well-drained, rocky soil, if they are kept wet, although it does best in sun, it will grow in light shade
7.
Sedum
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Sedum is a large genus of flowering plants in the family Crassulaceae, members of which are commonly known as stonecrops. The genus has been described as containing up to 600 species updated to 470 and they are leaf succulents found primarily in the Northern Hemisphere, but extending into the southern hemisphere in Africa and South America. The plants vary from annual and creeping herbs to shrubs, the flowers usually have five petals, seldom four or six. There are typically twice as many stamens as petals, various species formerly classified as Sedum are now in the segregate genera Hylotelephium and Rhodiola. Well-known European Sedums are Sedum acre, Sedum album, Sedum dasyphyllum, Sedum reflexum and Sedum hispanicum, Sedum demonstrates a wide variation in chromosome numbers, and polyploidy is common. Chromosome number is an important taxonomic feature, linnaeus originally described 16 species of European Sedum. There are now thought to be approximately 55 European species, in particular, Sedum spathulifolium is the host plant of the endangered San Bruno elfin butterfly of San Mateo County, California. Many sedums are cultivated as garden plants, due to their interesting and attractive appearance, the various species differ in their requirements, some are cold-hardy but do not tolerate heat, some require heat but do not tolerate cold. Sedum reflexum, known as prickmadam, stone orpine, or crooked yellow stonecrop, is used as a salad leaf or herb in Europe. It has a slightly astringent sour taste, Sedum divergens, known as spreading stonecrop, was eaten by First Nations people in Northwest British Columbia. The plant is used as a salad herb by the Haida and it is common in the Nass Valley of British Columbia. Biting Stonecrop contains high quantities of alkaloids, which give it a sharp, peppery, acrid taste. Sedum can be used to provide a covering in green roofs. Fords Dearborn Truck Plant’s living roof has 450,000 square feet of sedum, rolls-Royce Motor Cars plant in Goodwood, England, has a 242,000 square feet roof complex covered in Sedum, the largest in the United Kingdom. Nintendo of Americas roof is covered in some 75,000 square feet of Sedum, media related to Sedum at Wikimedia Commons Data related to Sedum at Wikispecies Sedum. Drought Smart Plants Sedum Society Sedum Yellow Stonecrop
8.
Agriculture
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Agriculture is the cultivation and breeding of animals, plants and fungi for food, fiber, biofuel, medicinal plants and other products used to sustain and enhance human life. Agriculture was the key development in the rise of human civilization. The study of agriculture is known as agricultural science, the history of agriculture dates back thousands of years, and its development has been driven and defined by greatly different climates, cultures, and technologies. Industrial agriculture based on large-scale monoculture farming has become the dominant agricultural methodology, genetically modified organisms are an increasing component of agriculture, although they are banned in several countries. Agricultural food production and water management are increasingly becoming global issues that are fostering debate on a number of fronts, the major agricultural products can be broadly grouped into foods, fibers, fuels, and raw materials. Specific foods include cereals, vegetables, fruits, oils, meats, fibers include cotton, wool, hemp, silk and flax. Raw materials include lumber and bamboo, other useful materials are also produced by plants, such as resins, dyes, drugs, perfumes, biofuels and ornamental products such as cut flowers and nursery plants. The word agriculture is a late Middle English adaptation of Latin agricultūra, from ager, field, Agriculture usually refers to human activities, although it is also observed in certain species of ant, termite and ambrosia beetle. To practice agriculture means to use resources to produce commodities which maintain life, including food, fiber, forest products, horticultural crops. This definition includes arable farming or agronomy, and horticulture, all terms for the growing of plants, even then, it is acknowledged that there is a large amount of knowledge transfer and overlap between silviculture and agriculture. In traditional farming, the two are often combined even on small landholdings, leading to the term agroforestry, Agriculture began independently in different parts of the globe, and included a diverse range of taxa. At least 11 separate regions of the Old and New World were involved as independent centers of origin, wild grains were collected and eaten from at least 105,000 years ago. Pigs were domesticated in Mesopotamia around 15,000 years ago, rice was domesticated in China between 13,500 and 8,200 years ago, followed by mung, soy and azuki beans. Sheep were domesticated in Mesopotamia between 13,000 and 11,000 years ago. From around 11,500 years ago, the eight Neolithic founder crops, emmer and einkorn wheat, hulled barley, peas, lentils, bitter vetch, chick peas and flax were cultivated in the Levant. Cattle were domesticated from the aurochs in the areas of modern Turkey. In the Andes of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, coca, llamas, alpacas, sugarcane and some root vegetables were domesticated in New Guinea around 9,000 years ago. Sorghum was domesticated in the Sahel region of Africa by 7,000 years ago, cotton was domesticated in Peru by 5,600 years ago, and was independently domesticated in Eurasia at an unknown time
9.
Kalanchoe blossfeldiana
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Kalanchoe blossfeldiana is a herbaceous and commonly cultivated house plant of the genus Kalanchoe native to Madagascar. It is known by the English common names flaming Katy, Christmas kalanchoe, florist kalanchoe, Kalanchoe blossfeldiana is in the Kalanchoe section of the Kalanchoe genus, with a description of the plant published in 1934. The specific epithet blossfeldiana is in tribute to German hybridiser and botanist Robert Blossfeld, the common name Christmas Kalanchoe comes from the plants flamboyant and colourful blooms in winter. The plant has green, shiny and textured glossy foliage which stays green all year round, the scallop-edged and ovate leaves are arranged in an opposite/subopposite fashion, are simple in type with crenate margins and an oblong shape. The arrangement of the veins in a leaf can be absent or very hard to see, the leaf blades are 5–10 cm. long. K. blossfeldiana flowers in autumn to early winter, each flower has four petals and can be one of a wide variety of colours, from the dark reds and pinks to oranges, golds. The ovary is tetracarpellary and apocarpous while stamens are four in number and are epipetalous, the inflorescences are born by peduncles which are higher up than the leaves and are terminal in nature. Parts of Kalanchoe blossfeldiana are poisonous if ingested, while generally disease free, Kalanchoe blossfeldiana can be damaged by pest insects such as Otiorhynchus sulcatus or mealybugs
10.
Cotyledon orbiculata
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Cotyledon orbiculata, commonly known as pigs ear or round-leafed navel-wort, is a South African succulent plant belonging to the Cotyledon genus. C. orbiculata is a variable species that grows to approximately 1.3 m in height. It has gray-green leaves that can be up to 13 by 7 cm with a powdery substance on them that helps reflect sunlight. The shape of the leaves was thought to have a resemblance to a pigs ear, the bell-shaped flowers are small, usually less than 3 cm in length, and droop from the top of a 60 cm tall stalk. The flowers are usually orange-red but yellow varieties also exist, native to South Africa, it is popular in gardens in many countries. In the wild, it grows naturally in rocky outcrops in grassy shrubland, in New Zealand, it is considered an invasive plant and is listed on the National Pest Plant Accord. C. orbiculata has a number of medicinal uses, in South Africa, the fleshy part of the leaf is applied to warts and corns. Heated leaves are used as poultices for boils and other inflammations, single leaves may be eaten as a vermifuge and the juice has been used to treat epilepsy. However, the leaves contain a bufanolide called cotyledontoxin, which is toxic to sheep, goats, horses, cattle, poultry, and dogs, causing a condition known as cotyledonosis
11.
Crassulacean acid metabolism
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Crassulacean acid metabolism, also known as CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, the pre-collected CO2 is concentrated around the enzyme RuBisCO, increasing photosynthetic efficiency. This metabolism was first studied in plants of the Crassulaceae family, the first time it was studied, Crassula was used as a model organism. The term CAM may have coined by Ranson and Thomas in 1940. It was observed by the botanists Ranson and Thomas, in the Crassulaceae family of succulents and its name refers to acid metabolism in Crassulaceae, not the metabolism of crassulacean acid. CAM is an adaptation for increased efficiency in the use of water, during the night, a plant employing CAM has its stomata open, allowing CO2 to enter and be fixed as organic acids that are stored in vacuoles. During the day the stomata are closed, and the carbon is released to the Calvin cycle so that photosynthesis may take place, the carbon dioxide is fixed in the cytoplasm of mesophyll cells by a PEP reaction similar to that of C4 pathway. But, unlike the C4 mechanism, the organic acids are stored in vacuoles for later use. The latter cannot operate during the night because the reactions that provide it with ATP. The most important benefit of CAM to the plant is the ability to leave most leaf stomata closed during the day, plants employing CAM are most common in arid environments, where water comes at a premium. Plants using only C3 carbon fixation, for example, lose 97% of the water they uptake through the roots to transpiration - a high cost avoided by plants able to employ CAM. The C4 pathway bears resemblance to CAM, both act to concentrate CO2 around RuBisCO, thereby increasing its efficiency, CAM concentrates it temporally, providing CO2 during the day, and not at night, when respiration is the dominant reaction. C4 plants, in contrast, concentrate CO2 spatially, with a RuBisCO reaction centre in a bundle sheath cell being inundated with CO2, at low temperatures, plants using CAM open their stomata, CO2 molecules diffuse into the spongy mesophylls intracellular spaces and then into the cytoplasm. Here, they can meet phosphoenolpyruvate, which is a phosphorylated triose, during this time, the plants are synthesizing a protein called PEP carboxylase kinase, whose expression can be inhibited by high temperatures and the presence of malate. PEP-C kinase phosphorylates its target enzyme PEP carboxylase, phosphorylation dramatically enhances the enzymes capability to catalyze the formation of oxalacetate, which can be subsequently transformed into malate by NAD+ malate dehydrogenase. Malate is then transported via malate shuttles into the vacuole, where it is converted into the storage form malic acid, in contrast to PEP-C kinase, PEP-C is synthesized all the time but almost inhibited at daylight either by dephosphorylation via PEP-C phosphatase or directly by binding malate. The latter is not possible at low temperatures, since malate is efficiently transported into the vacuole, in daylight, plants using CAM close their guard cells and discharge malate that is subsequently transported into chloroplasts. There, depending on plant species, it is cleaved into pyruvate, CO2 is then introduced into the Calvin cycle, a coupled and self-recovering enzyme system, which is used to build branched carbohydrates
12.
Crassula
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Crassula is a genus of succulent plants containing about 1480 accepted species, including the popular jade plant. They are native to parts of the globe, but cultivated varieties originate almost exclusively from species from the Eastern Cape of South Africa. Crassulas are usually propagated by stem or leaf cuttings, most cultivated forms will tolerate some small degree of frost, but extremes of cold or heat will cause them to lose foliage and die. The name crassula comes from the Latin, meaning thick, referring to the thickening of the succulent leaves
Data related to Crassulaceae at Wikispecies