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[Latin, cardoon, from Greek kaktos.]
The common name for any member of the cactus family (Cactaceae). There are 120 genera with perhaps 1700 species, nearly all indigenous to America. The cacti are among the most extremely drought-resistant plants, and consequently they thrive in very arid regions. The group is characterized by a fleshy habit, presence of spines and bristles, and large, brightly colored, solitary flowers. There is a great variety of body shapes and patterns, and many of the species are grown as ornamentals or oddities. A few have edible fruits. The cochineal insect, which produces a valuable red dye, is cultivated chiefly on the cochineal cactus (Nopalea coccinellifera). The saguaro (Cereus giganteus) of Arizona and Sonora is the largest of the cacti, attaining a height of 70 ft (21 m). See also Caryophyllales.
Cacti grow in many habitats, ranging from epiphytes living on trees in dense tropical forests to large, isolated plants in deserts. In all cases, various adaptations that lead to water conservation are apparent. For example, the stems of most cacti are massive and can store large amounts of water that sustain the plants during prolonged drought. Adaptations for water conservation also occur on a metabolic level. Cacti have a thick waxy cuticle on their stems, which acts as a waterproofing skin. Also, the pores (called stomata or stomates) in the cactus skin that are necessary for the uptake of carbon dioxide (CO2) from the atmosphere tend to open only at night. Much less water (generally 80–90% less) is lost by transpiration during the nocturnal opening of stomata by cacti compared with the daytime stomatal opening of most other plants. The opening of stomata at night presents a problem for photosynthesis, which requires light. Specifically, photosynthesis uses atmospheric carbon dioxide and the energy of sunlight to form sugars in the chloroplasts of the chlorenchyma. During the night malic acid accumulates in the large vacuoles of cactus chlorenchyma cells; during the next daytime, when the stomata have closed, carbon dioxide is released from the accumulated acid within the stems of cacti. Carbon dioxide is then fixed into sugars via photosynthesis when sunlight is available as the energy source. This process, known as crassulacean acid metabolism (CAM) because it was first discovered in the plant family Crassulaceae, is crucial for the adaptation of cacti to the dry conditions characteristic of deserts. Its water-conserving attribute is also important in the increasing cultivation of cacti for their fruits and as fodder for livestock, particularly cattle.
For more information on cactus, visit Britannica.com.
The plants vary from small, round globes to epiphytes, vines, and large treelike forms. The reduced leaf surface, the enlarged fleshy stem, which is well fitted to store water and to retain it, and the ramified and extensive root system (much reduced in cultivated cacti) make the plant particularly adapted to regions of high temperature and long dry periods. Cacti are not restricted to desert regions, however, for in America they range from the tropics into Canada.
Most cacti bloom in the spring for a very short period, sometimes for only a few hours. The blossoms are noticeably sensitive to light, and often different species blossom only at specific times of the day. One of the most famous of the cacti is the night-blooming cereus usually classified as Selenicereus or C. grandiflora (several other night-blooming cactus species bear the same common name). Its fragrant blossoms unfold at a visible rate after sunset and last only a single night. In many of its native habitats the flowering of this cactus is celebrated with festivals.
Economic Importance
The largest cactus genus is Opuntia, jointed-stemmed species recognizable by the fleshy stems made up of either cylindrical (in the cane cacti and the chollas) or flattened (in the prickly pears) joints called pads. The large pear-shaped berries of several of these species are edible, e.g., the cultivated varieties of the Indian fig and the tuna. This fruit is common in Mexican markets; the plants have been widely naturalized in the Mediterranean countries, Australia, and elsewhere as a source of food. Most opuntias grow so rapidly to a large and ungainly size that they are unsuitable for cultivation as ornamentals, and in the wild often become weeds.
However, the major economic importance of the cactus family is in the florists' trade. Among those cultivated for their showy blossoms are the Christmas cactus (Zygocactus) and species of Echinocereus and of Epiphyllum, the orchid cactus. The pincushion cacti (Mammillaria), the golden ball cactus (Echinocactus), and the hedgehog cactus (Echinopsis) are among the many grown as oddities for their curious appearance.
The nopal (Nopalea coccinellifera) is the cactus traditionally cultivated as a host for the cochineal insect, and the hallucinatory drug mescaline occurs in the genera Lophophora (peyote) and Trichocereus. Other cacti are used as a substitute for wood, as stock feed, and for hedges.
Classification
Cactus is classified in the division Magnoliophyta, class Magnoliopsida, order Caryophyllales, family Cactaceae.
Bibliography
See L. Benson, The Cacti of the United States and Canada (1982) and A. C. Gibson and P. S. Nobel, The Cactus Primer (1986).
Cacti are succulent perennials that are native to arid and semi-arid regions and are cultivated extensively, except where freezes regularly occur. The land area devoted to cactus cultivation in 2001 was about 1.8 million hectares (4.4 million acres), mostly for fodder, and over half of which was in northern Africa and northeastern Brazil. Cacti are also cultivated in over twenty countries for their fruits, which commercially fall into three categories: cactus pears, which are the fruits of the prickly pear Opuntia ficus-indica and certain other cacti with flat stems (cladodes), and represent over 90% of the cactus fruits sold; pitahayas, which are the fruits of vine cacti in the genera Hylocereus and Selenicereus; and pitayas, which are the fruits of columnar cacti. Young cladodes are consumed as a vegetable (nopalitos), particularly in Mexico. Nearly all cacti employ a photosynthetic pathway known as Crassulacean acid metabolism (CAM), in which the stomates (shoot pores that allow CO2 entry) open primarily at night, when temperatures are lower and water loss is lower than for the overwhelming majority of plants, whose stomates open during the daytime. The best known edible CAM plant is pineapple, which is cultivated on about half as much area as cacti. Because of their lower water loss, cacti and other CAM plants thrive in dry regions (and also require little or no irrigation when cultivated in other regions.
History
Although evidence for cacti in human diets goes back more than 8,000 years in present-day Mexico, worldwide consumption has developed only in the last few hundred years. Cacti were introduced into Europe in 1495 from the second trip of Christopher Columbus to the New World. Opuntia ficus-indica spread across the Mediterranean region in the sixteenth century, where it readily grew under the local semi-arid conditions. Also in the sixteenth century, Spaniards introduced Hylocereus undatus into the Philippines, whence it spread throughout southeast Asia. In the nineteenth century, it became established in Viet Nam and is now extensively cultivated in the Mekong Delta, where its tasty fruit with red peel and white pulp is called "dragon fruit." Also in the nineteenth century, the columnar Stenocereus queretaroensis was domesticated in Jalisco, Mexico. None of these species received much agronomic attention until the end of the twentieth century, and even then the money for research and development was meager. Both fruit crops and young cladodes used as vegetables require much hand labor. Although machines have been developed to remove the irritating small spines (termed "glochids") from cactus pears, many improvements in their cultivation await future research.
Fruits
Fruits of many cacti are edible. Indeed, the Seri Indians of the southwestern United States and northwestern Mexico consumed fruits from over twenty species, including those of the saguaro cactus (Carnegiea gigantea), used by various Native Americans for fruits and wine. Fruits collected from the wild influenced the species selected for domestication. Such selections involved various species of Opuntia in Mexico, eventually leading to the presently planted cultivars.
Cactus pear. The fruits of Opuntia ficus-indica and a few other prickly pears are harvested in the summer from plants that are one to three meters tall. Harvest can be delayed by removing the early flowers, as is commonly done in Sicily, leading to a second harvest in the autumn that is more valuable per fruit due to lessened competition from other species. One-year-old cladodes can bear five to fifteen fruits each; terminal cladodes with fewer fruits tend to bear larger ones (over 150 g each), which command higher prices. After harvesting, the fruits must have the glochids removed mechanically, after which they are often packaged by color and weight. Fruits with red pulp are prized in the United States and certain European countries, whereas greenish pulp for mature fruits is generally preferred in Mexico. Although sold in supermarkets worldwide, fruits are also sold by street vendors, who slice the peel and provide the exposed pulp directly to the consumer. The relatively large seeds are a detriment to fruit consumption by many, but the seeds are harmless and readily swallowed by aficionados.
The country with the greatest land area devoted to cactus pear cultivation is Mexico (Table 1). Annual production can be over fifteen tons fresh weight per hectare under intensive management. In Mexico, Sicily, Israel, and the United States, most production is from commercial plantations, whereas in other Latin American countries and in northern Africa, a large amount of the fruit is collected from hedges and other informal plantings.
Pitahayas and pitayas. The most widely cultivated pitahaya is Hylocereus undatus, which in 2001 was cultivated on about 12,000 hectares in many countries, including Viet Nam, Taiwan, the Philippines, Mexico, Guatemala, Peru, Colombia, and Israel. It is a vine that is trained to grow on posts, trellises, or arbors. Its relatively large fruits (generally 250 to 500 g) are harvested after the peel, which has no spines or glochids, turns red. The pulp is whitish with small black seeds. Other species of Hylocereus and Selenicereus megalanthus have peels and pulps of various colors, leading to a wide choice of tasty and visually appealing fruits.
Table 1
| Land areas and harvests for fruit production by Opuntiaficus-indica and closely related species in 2001 | ||
| Country | Area (hectares) | Annual harvest (tons fresh weight) |
| Argentina | 900 | 8,000 |
| Bolivia | 1,300 | 3,500 |
| Chile | 1,200 | 9,000 |
| Israel | 400 | 7,000 |
| Italy | 7,500 | 80,000 |
| Mexico | 70,000 | 400,000 |
| Northern Africa (Algeria, Morocco, Tunisia) | ~20,000 | — |
| South Africa | 200 | 1,500 |
| United States | 200 | 3,600 |
Although their cultivation is expanding rapidly, in 2001 pitayas were harvested on only about 3,000 hectares worldwide, mostly in Mexico, from species like Cereus peruvianus, and especially Stenocereus queretaroensis and other Stenocereus species. Fruits grow along the main stem and branches about two to six meters above the ground, requiring a pole with a basket-like attachment for harvest of individual fruits. Fruits of Stenocereus queretaroensis have an attractive and tasty dark red or purple pulp with small seeds (like those in kiwis) that are easily swallowed. However, the fruits tend to split within two or three days after harvest, requiring rapid local consumption.
Vegetables
Tender young cladodes about 10 to 15 cm long of Opuntia ficus-indica, Opuntia robusta, and a few related species are used in Mexico as nopalitos. About 6,000 hectares were cultivated for this purpose in 2001, and nopalitos are also prepared from plants in the wild or growing around houses, or as hedges. The raised portions of the stem containing spines and glochids are readily removed with a knife or by machine. The cladodes are then generally sliced or diced and blanched in a weak saline solution for a few minutes to remove excess mucilage. After draining, the material can be cooked, yielding a vegetable with a taste not unlike string beans or okra. Because of their high fructose and mucilage content, nopalitos are highly recommended for people with type II diabetes. Often the blanched material is pickled and used as a relish or in salads. More than thirty companies sold pickled nopalitos in Mexico in 2001, and this product is in supermarkets worldwide.
Other Uses
Other uses of cacti range from candy made from the stems of barrel cacti that have been infused with a sugar solution to peyote from dried stems of Lophophora williamsii, used by Native Americans for ceremonial purposes. Flowers have been used for medicinal purposes and to make perfume. The seeds of cacti such as Opuntia ficus-indica have been dried, ground, and then used as a flavoring paste for cooking. Carminic acid, an important red dye for food coloring, can be extracted from dried cochineal insects that feed on Opuntia ficus-indica. Although most cactus pears are consumed fresh, sorbets and marmalades are also prepared from the fruits. The strained pulp of fresh fruits is used as a fruit drink or fermented to make wine. Fruits of cactus pears are also partially dried and sold in brick-sized blocks in Mexico. More than thirty brands of dried and powdered cladodes are sold in Mexico as a dietary supplement. The range of edible products from cacti is indeed great and their use is steadily increasing, as more people become willing to try new and natural foods, and growers search for crops that do not need irrigation.
Bibliography
Mizrahi, Yosef, Avinoam Nerd, and Park S. Nobel. "Cacti as Crops." In Horticultural Reviews 18 (1997): 291–319.
Nobel, Park S. Los Incomparables Agaves y Cactos. Translated by Edmundo Garcia Moya. Mexico City: Editorial Trillas, 1998.
Nobel, Park S. Remarkable Agaves and Cacti. New York: Oxford University Press, 1994.
Nobel, Park S., editor. Cacti: Biology and Uses. Berkeley, California: University of California Press, 2002.
Valles Septién, Carmen, editor. Succulentas Mexicanas/Cactáceas. Mexico City: CVS Publicaciones, 1997.
—Park S. Nobel
A plant in the immense Cactaceae family. The majority are spiny succulent plants. Most are native to the dry desert regions of the Americas, but a few are tropical epiphytes.
That nature preserve featured giant saguaro cactus.
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See also taxonomy of the Cactaceae |
A cactus (plural cacti, cactuses or cactus) is any member of the succulent plant family Cactaceae, native to the Americas. They are often used as ornamental plants, but some are also crop plants.
Cacti are distinctive and unusual plants, which are adapted to extremely arid and hot environments, showing a wide range of anatomical and physiological features which conserve water. Their stems have expanded into green succulent structures containing the chlorophyll necessary for life and growth, while the leaves have become the spines for which cacti are so well known.
Cacti come in a wide range of shapes and sizes. The tallest is Pachycereus pringlei, with a maximum recorded height of 19.2 m,[1] and the smallest is Blossfeldia liliputiana, only about 1 cm diameter at maturity.[2] Cactus flowers are large, and like the spines and branches arise from areoles. Many cactus species are night blooming, as they are pollinated by nocturnal insects or small animals, principally moths and bats. Cacti's sizes range from small and round to pole-like and tall.
The cacti are succulent plants that grow either as trees, shrubs or in the form of ground cover. Most species grow on the
ground, but there is also a whole range of epiphytic species. In most species, except for the
sub-family of the Pereskioideae (see image), the leaves are greatly or entirely reduced. The
flowers, mostly radially symmetrical and hermaphrodite, bloom either by day or by night, depending on species. Their shape varies
from tube-like through bell-like to wheel-shaped, and their size from 0.2 to 15-30 meters. Most of them have numerous
The life of a cactus is seldom longer than 300 years, and there are cacti which live only 25 years (although these flower as early as their second year). The Saguaro cactus (Carnegiea gigantea) grows to a height of up to 15 metres (the record is 17 metres 67cm), but in its first ten years it grows only 10 centimetres. The "mother-in-law's cushion" (Echinocactus grusonii) reaches a height of 2.5 meters and a diameter of 1 meter and - at least on the Canaries - is already capable of flowering after 6 years. The diameter of cactus flowers ranges from 5 to 30 cm; the colors are often conspicuous and spectacular. Sometimes they are weak but have to store water.
Cacti are almost exclusively New World plants. This means that they are native only in North America, South America, and the West Indies. There is however one exception, Rhipsalis baccifera; this species has a pantropical distribution, occurring in the Old World tropical Africa, Madagascar and Sri Lanka as well as in tropical America. The Tehuacán Valley of Mexico has one of the richest occurrences of cacti in the world.[4] This plant is thought to be a relatively recent colonist in the Old World (within the last few thousand years), probably carried as seeds in the digestive tracts of migratory birds. Many other cacti have become naturalized to similar environments in other parts of the world after being introduced by people.
Cacti are believed to have evolved in the last 30 to 40 million years. Long ago, the Americas were joined to the other continents, but separated due to continental drift. Unique species in the New World must have developed after the continents had moved apart. Significant distance between the continents was only achieved in around the last 50 million years. This may explain why cacti are so rare in Africa the continents had already separated when cacti evolved. Many succulent plants in both the Old and New World bear a striking resemblance to cacti, and are often called "cactus" in common usage. This is, however, due to parallel evolution; none of these are closely related to the Cactaceae.
Prickly pears (genus Opuntia) were imported into Australia in the 19th century to be used as a natural agricultural fence and to establish a cochineal dye industry, but quickly became a widespread weed. This invasive species is inedible for local herbivores and has rendered 40,000 km² of farming land unproductive.
Some environments, such as deserts, semi-deserts and dry steppes, receive little water in the form of precipitation. Plants that inhabit these dry areas are known as xerophytes, and many of them are succulents, with thick or reduced, "succulent", leaves. Apart from a very few exceptions (for example, the genus "Rhodocactus") all cacti are succulent plants, although not all succulent plants are cacti. Like other succulents, these cacti have a range of specific adaptations that enable them to survive in these environments.
Cacti have never lost their leaves completely; they have only reduced the size so that they reduce the surface area through which water can be lost by transpiration. In some species the leaves are still remarkably large and ordinary while in other species they have became microscopic but they still contain the stomata, xylem and phloem. Certain cactus species have also developed ephemeral leaves, which are leaves that last for a short period of time when the stem is still in its early stages of development. A good example of a species that have ephemeral leaves is the Opuntia ficus indicia, better known as the prickly pear. Cactus have also developed spines which allow less water to evaporate through transpiration by shading the plant, and defend the cactus against water-seeking animals. The spines grow from specialized structures called areoles. Very few members of the family have leaves, and when present these are usually rudimentary and soon fall off; they are typically awl-shaped and only 1-3 mm long. Two genera, Pereskia and Pereskiopsis, do however retain large, non-succulent leaves 5-25 cm long, and also non-succulent stems. Pereskia has now been determined to be the ancestral genus from which all other cacti evolved.[5]
Enlarged stems carry out photosynthesis and store water. Unlike many other succulents, the stem is the only part of a true cactus where this takes place. Much like many other plants that have waxy coatings on their leaves, Cacti often have a waxy coating on their stems to prevent water loss. This works by preventing water from spreading on the surface and allowing water to trickle down the stem to be absorbed by the roots and used for photosynthesis. Cacti have a thick, hard-walled, succulent stem - when it rains, water is stored in the stem. The stems are photosynthetic, green, and fleshy. The inside of the stem is either spongy or hollow (depending on the cactus). A thick, waxy coating keeps the water inside the cactus from evaporating.
The bodies of many cacti have become thickened during the course of evolution, and form water-retentive tissue and in many cases assume the optimal shape of the sphere (combining highest possible volume with lowest possible surface area). By reducing its surface area, the body of the plant is also protected against excessive sunlight.
Most cacti have a short growing season and long dormancy. For example, a fully-grown Saguaro cactus (Carnegiea gigantea) can absorb up to 3,000 litres of water in ten days. This is helped by cacti's ability to form new roots quickly. Only two hours after rain following a relatively long drought the formation of new roots begins. Apart from a few exceptions an extensively ramified root system is formed, which spreads out immediately beneath the surface. The salt concentration in the root cells is relatively high, so that when moisture is encountered, water can immediately be absorbed in the greatest possible quantity.
But the plant body itself is also capable of absorbing moisture (through the epidermis and the thorns), which for plants that are exposed to moisture almost entirely, or indeed in some cases solely, in the form of fog, is of the greatest importance for sustaining life.
Most cacti have very shallow roots that can spread out widely close to the surface of the ground to collect water, an adaptation to infrequent rains; in one examination, a young Saguaro only 12 cm tall had a root system covering an area 2 meters in diameter, but with no roots more than 10 cm deep.[6] The larger columnar cacti also develop a taproot, primarily for anchoring but also to reach deeper water supplies and mineral nutrients.[6]
One feature distinguishes the cacti from all other plants: cacti possess areoles, as they are known. The areole appears like a cushion with a diameter of up to 15 mm and is formed by two opposing buds in the angles of a leaf. From the upper bud develops either a blossom or a side shoot, from the lower bud develop thorns. The two buds of the areoles can lie very close together, but they can also sometimes be separated by several centimetres.
Like other succulents in the families of the Crassulaceae, Agavaceae (agaves), Euphorbiaceae (euphorbias), Liliaceae (lilies), Orchidaceae (orchids) and Vitaceae (vines), cacti reduce water loss through transpiration by Crassulacean acid metabolism.[6] Here, transpiration does not take place during the day at the same time as photosynthesis, but at night. The plant stores the carbon dioxide chemically linked to malic acid until the daytime. During the day the stomata are closed and the plant releases the stored CO2 and uses it for photosynthesis. Because transpiration takes place during the cool humid night hours, water loss through transpiration is significantly reduced.
Some cactus flowers form long tubes (up to 30 centimetres) so that only moths can reach the nectar and thus pollinate the blossoms. There are also specialisations for bats, humming birds and particular species of bees. The duration of flowering is very variable. Many flowers, for example those of Selenicereus grandiflorus (Queen of the Night) are only fully open for two hours at night. Other cacti flower for a whole week. Most cacti are self-incompatible, and thus require a pollinator. A few are autogamous and are able to pollinate themselves. Fraileas only opens their flowers completely in exceptional circumstances; they mostly pollinate themselves with their flowers closed ("cleistogamy"). The flower itself has also undergone a further development: the ovary tends to become a completely protected area, protected by thorns, hairs and scales. Seed formation is very prolific, and the fruits are mostly fleshy, pleasant tasting and conspicuously coloured. Goats, birds, ants, mice and bats contribute significantly to the spreading of the seeds.
Because of the plants' high water-retention ability, detached parts of the plant can survive for long periods and are able to grow new roots everywhere on the plant body.
Some cacti are able to reproduce by budding. These cacti grow on one another. While they appear to be one plant they are actually several cacti. These types of cacti will survive if separated from the main plant. They will take root and start the budding process as the main plant.
Among the remains of the Aztec civilization, cacti can be found repeatedly in pictorial representations, sculpture and drawings, principally Echinocactus grusonii. This cactus, also known as "Mother-in-law's Cushion," has great ritual significance - human sacrifices were carried out on these cacti.[citation needed] Tenochtitlan (the earlier name of Mexico City) means "place of the sacred cactus." The coat of arms of Mexico to this day shows an eagle, snake, and cactus.
Economic exploitation of the cactus can also be traced back to the Aztecs. The North American Indians exploit the alkaloid content of many cacti for ritual purposes. Today, besides their use as foodstuffs (jam, fruit, vegetables), their principal use is as a host for the cochineal insect, from which a red dye (carmine) is obtained which is used in Campari or high-quality lipsticks. Particularly in South America dead pillar cacti yield valuable wood for construction. Some cacti are also of pharmaceutical significance.
From the moment of their discovery by early European explorers cacti have aroused much interest: Christopher Columbus brought the first melocactuses to Europe. Scientific interest in them began in the 17th century. By 1737, twenty-four species were known, which Linnaeus grouped together as the genus "Cactus". With the passage of time cacti enjoyed increasing popularity: sometimes they were of scientific interest only; at other times as fashionable plants they enjoyed a real boom.
From the beginning of the 20th century interest in cacti has increased steadily, interrupted only by the two world wars. This was accompanied by a rising commercial interest, the negative consequences of which culminated in raids on the cacti' native habitats, resulting in the extermination of many species. Through the great number of cactus admirers, whether their interest is scientific or hobby-oriented, new species and varieties are even today discovered every year.
All cacti are covered by the Convention on International Trade in Endangered Species of Wild Fauna and Flora, and many species by virtue of their inclusion in Appendix 1 are fully protected.
Some countries have a rather contradictory attitude to species protection. In Mexico for example to be caught in the act of digging up cacti carries a prison sentence, but cactus habitats are destroyed for the construction of new roads and electricity lines. To be borne in mind here is that some cactus habitats have a total area of no more than 1,000 square meters.[citation needed][dubious ] If this habitat is destroyed, either by construction or by plundering, the species growing there is lost for posterity if it is endemic (ie, growing in that one spot and nowhere else).
The Moche people of ancient Peru worshiped agriculture and often depicted the cactus in their art. [7]
Cacti, cultivated by people worldwide, are a familiar sight as potted plants, houseplants or in ornamental gardens in warmer climates. They often form part of xeriphytic (dry) gardens in arid regions, or raised rockeries. Some countries, such as Australia, have water restrictions in many cities, so drought-resistant plants are increasing in popularity. Numerous species have entered widespread cultivation, including members of Echinopsis, Mammillaria and Cereus among others. Some, such as the Golden Barrel Cactus, Echinocactus grusonii, are prominent in garden design. Cacti are commonly used for fencing material where there is a lack of either natural resources or financial means to construct a permanent fence. This is often seen in arid and warm climates, such as the Masai Mara in Kenya. This is known as a cactus fence. Cacti fences are often used by homeowners and landscape architects for home security purposes. The sharp thorns of the cactus deter unauthorized persons from entering private properties, and may prevent break-ins if planted under windows and near drainpipes. The aesthetic characteristics of some species, in conjunction with their home security qualities, makes them a considerable alternative to artificial fences and walls.
As well as garden plants, many cacti have important commercial uses; some cacti bear edible fruit, such as the prickly pear and Hylocereus, which produces Dragon fruit or Pitaya. Opuntia are also used as host plants for cochineal bugs in the cochineal dye industry in Central America.
The Peyote, Lophophora williamsii, is a well-known psychoactive agent used by Native
Americans in the Southwest of the
The word cactus is ultimately derived from Greek Κακτος kaktos, used in classical Greek for a species of spiny thistle, possibly the cardoon, and used as a generic name, Cactus, by Linnaeus in 1753 (now rejected in favor of Mammillaria). There is some dispute as to the proper plural form of the word; as a Greek loan into English, the correct plural in English would be "cactoi" or "cactuses". However, as a word in Botanical Latin (as distinct from Classical Latin), "cactus" would follow standard Latin rules for pluralization and become "cacti", which has become the prevalent usage in English. Regardless, cactus is popularly used as both singular and plural, and is cited as both singular and plural by the Random House Unabridged Dictionary (2006).
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)
Deutsch (German)
n. - Kaktee, Kaktus
Português (Portuguese)
n. - cacto (m)
Español (Spanish)
n. - cactus, cacto
中文（简体） (Chinese (Simplified))
仙人掌
中文（繁體） (Chinese (Traditional))
n. - 仙人掌
العربيه (Arabic)
(الاسم) صبير أو صبار نبات صحراوي
עברית (Hebrew)
n. - צבר, קקטוס
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