Opuntia

Opuntia is echios native to the Galápagos Islands. It belongs to the large, tree-like growing Opuntienarten.

The prickly pear ( Opuntia ) are a genus of flowering plants of the cactus family ( Cactaceae ). With about 190 species it is one of the most species-rich genera within the cactus. Its distribution area covers large parts of North and South America including the Caribbean. With almost half of the species is the focus of distribution in Mexico. The Aztec legend of the founding of Tenochtitlán, which describes how an eagle sitting on a Opuntia and fights with a snake, be still reflects in the Mexican coat of arms.

The use of some Opuntienarten can be traced to the time of the Paracas culture traced. In addition to the use of the shoots and fruits as food Opuntia were especially cultivated for the extraction of the dye cochineal red. In recent years, Opuntia are increasingly cultivated in several countries as feed. As invasive neophytes some Opuntienarten spread so greatly in different areas, that they had to be fought with biological agents.

  • 3.1 pollination
  • 3.2 agamospermy
  • 3.3 spread
  • 6.1 Etymology
  • 6.2 symbolism
  • 8.1 Use as a coloring agent 8.1.1 Karminerzeugende Cochenillenschildläuse
  • 8.1.2 Opuntienfrüchte

Description

Vegetative characteristics

Opuntia grow shrubby to tree-like, are erect or creeping and occasionally form clusters or mats. They are often richly branched and can reach heights of growth of 10 meters and more. Some species have a well-trained, long round stem, which is divided recognizable at the beginning and appears throughout the ages. The individual drive sections, often called limbs are noticeably linked. The green or sometimes reddish to purple shoots consist of flattened, leaf-like segments ( Platykladien ), which are round, oval, elliptical, cylindrical or rhomboid shaped. Your bald or finely hairy surface is almost smooth to bumpy. They are 2 to 60 ( rarely 120) inches long and 1.2 to 40 centimeters wide.

The usually elliptical, circular or reverse- egg-shaped areoles in the leaf axils ( axillae ) are 3-8 (rarely 10 ) mm long and 1-7 (rarely 10 ) mm wide. They are white, gray or yellow-brown to brown woolly. The Areolenwolle is aged white or gray to black. The small, sessile, fleshy leaves formed by the areoles are cylindrical to conical and fall off early. Glochids arise either at the edge of areola or form clumps. They are initially white, yellow to brown or reddish brown and later white to brown or reddish brown. The up to 15 (or more) acicular to pfriemlichen thorns that may be absent, are terete to angular - flattened in cross-section and to 75 ( rarely 170) millimeters long. The spines are white, yellow to brown, reddish-brown to gray or black with age and are gray to dark brown to black. Sometimes they are colored yellow or pale at the tips.

Flowers

With just a few exceptions (eg, Opuntia Opuntia stenopetala and quimilo ) bisexual and radial symmetry flowers grow on the edges of the driving sections. You individually are common and are of variable color. The outer tepals are green to yellow and tinged at the edges with the color of the inner tepals, which are pale yellow to orange and pink to red or purple colored. Rarely the flowers are white or have at the base a different color. The Perikarpell is busy ball - up and top-shaped with areolae and leaf-like scales. A flower tube is missing.

The stamens are arranged usually yellow or green and circular or spiral around the stylus. They show a pronounced thigmotaxis. In response to a tactile stimulus to curve in the direction of the stylus and then include it. The style is simple, hollow, usually green or yellow, but can also be pink, red or orange. The broad scar extends beyond the stamens also. The unicompartmental ovary contains several hundred ovules.

Fruit and seeds

The non- bursting, occasionally stalked fruits are individually, sometimes in clusters and are clavate to cylindrical, ovate or obovate shaped to almost spherical. They are 10 to 120 millimeters long and 8 to 120 millimeters wide. The fruits have a smooth or nodular surface and can, sometimes strongly, with thorns and bear glochids. They are fleshy and juicy or dry. Fleshy fruits are green, yellow or red to purple colored dry fruits yellowish brown to gray.

The fruits contain few to many, white to brown seeds, which are laterally flattened considerably. The seeds are circular to kidney-shaped. They are 3 to 10 millimeters long. The seed coat is hairy hairless or finely.

Genetics and age

The base chromosome number of the genus equivalent to that of all cactus. Polyploidy in the Opuntia, as with all genera of the family of Opuntioideae, often encountered.

In rat middens of the American bush rats, the only previous fossil remains of cactus were discovered. The dated to an age of about 24,000 years employing the C- 14 method groups are derived from a cylindrical Opuntia.

Life cycle

The seeds of Opuntia, Opuntia stricta, for example, are viable up to 15 years. For successful germination, the seeds need a dormancy of usually at least one year. To overcome this and to also allow the sowing freshly collected seeds were more or less successful attempts made ​​to treat the seeds mechanically or with acids. From sowing to germination pass a few days to several weeks. The seedlings can have a significant growth in length, so grow seedlings of Opuntia echios in the first year up to 25 centimeters. The seedlings of Opuntia include diet of many herbivores and need to survive the protection of other cacti or perennial plants among which they can grow.

In contrast to all other species of cactus can develop from the meristem of an areola either Kladien or flowers. The development of a flower bud to bloom lasts 21-47 days (maximum 75 days ). Are required 45-154 days for the ripening of the fruit. The longest maturity period was observed in Opuntia joconostle and was 224 days. The fruits are eaten by animals that spread the seeds with their excretions.

Ecology

Pollination

The flowers of Opuntia are visited by numerous Hymenoptera, some beetles, two species of butterflies and ten species of birds, not all of which contribute to pollination. In most Opuntia pollination is done by bees, as the flowers of Opuntia are particularly well adapted to these pollinators ( Melittophilie ). To collect pollen from the lower anthers, the bees run the pen along and thereby take the pollination before.

The majority of pollinating Hymenoptera are polylektisch, ie they are not specialized to a single plant family. The genera Ashmeadiella, Diadasia, Melissodes and Lithurge, however, are exclusively specialized in Opuntia Hymenoptera ( oligolektisch ). Of the genera Diadasia and Lithurge one assumes that they have evolutionarily developed together with the Opuntia ( coevolution ).

Some of the information disseminated on the Galápagos Islands Opuntienarten are pollinated by belonging to the Darwin finches basic Opuntia finches finch, sharp-beaked ground finch and cactus finch ( Geospiza scandens ). For the pollination of Opuntia Opuntia stenopetala quimilo and hummingbirds are responsible.

The Opuntia both self-pollination was ( with the pollen of the same flower ) and cross-pollination ( with pollen from another flower on the same plant ) and Xenogamie demonstrated ( with the pollen from another plant ).

Agamospermy

Cacti often form seeds without fertilization from ( agamospermy ). Most cases, these are formed from nucellus tissue adventitious ( sporophytic agamospermy ). Could Streptacantha In Opuntia diplospory be demonstrated in an embryo is formed from an unreduced egg.

Spread

Opuntia are not dependent on their propagation to certain animal species. Depending on the area of ​​distribution, these can be small or large mammals, birds, lizards and turtles that eat the fruits of Opuntia. In South Africa's Kruger National Park, for example, baboons and elephants were detected as containing Opuntia stricta. The home on the Galápagos Islands opuntias be disseminated among other things, the Galápagos rat ( Oryzomys bauri ). In the stomach of the animals the hard seed coat is attacked by the digestive juices and so the germination of the seeds increased ( digestive propagation ). In the Mexican highlands of San Luis Potosi one of the main propagator of Opuntia based there is the ant genus Pogonomyrmex ( ants spread ).

Opuntia spread not only by seed, but also by vegetative propagation. The flat rung many Opuntienarten are relatively easy to separate. If they fall to the ground, arise from the areoles first adventitious roots and eventually a new plant. Opuntia fragilis spreads probably only in this way. Rarer forms of spread use of an existing rhizome (eg Opuntia megarhiza ) or aboveground or underground runners (eg Opuntia polyacantha ).

Dissemination and locations

The distribution of Opuntia extends from southern Canada, where Opuntia fragilis with the spread at the northernmost cactus growing up in the south of Argentina. It ranges from the Caribbean to the east up to the Galápagos Islands in the west. Mexico is the main distribution area with about 75 species. Opuntia are naturalized in many countries, for example in the Mediterranean, South Africa or Australia.

Cacti grow in arid and semi-arid, and in temperate and tropical areas, at altitudes ranging from sea level to an altitude of 4700 meters. Some species such as Opuntia howeyi are extremely frost resistant and hardy even in Central Europe.

System

The cacti are the most species-rich genus within the subfamily Opuntioideae, which differs from the other sub- families of cactus by the presence of glochids and a hard, bony aril. The genus Opuntia of 1754, set up a year after the introduction of the binary nomenclature, by Philip Miller. The type species of the genus Cactus ficus- indica.

For many species of Opuntia, there is little reliable findings. This is especially true in the south of Mexico, the Caribbean and widespread in South America species. Complicating the taxonomic situation is that Opuntia among themselves readily form hybrids and have formed numerous forms in cultured human- species.

After Edward F. Anderson ( 2005) include the following species, subspecies and varieties of the genus Opuntia:

  • Opuntia acaulis
  • Opuntia aciculata
  • Opuntia tuna alco -
  • Opuntia ammophila
  • Opuntia amyclaea
  • Opuntia anacantha Opuntia anacantha var anacantha
  • Opuntia anacantha var kiska - loro
  • Opuntia anacantha var retrorsa
  • Opuntia anacantha var utkilio
  • Opuntia var basilar basilar
  • Opuntia basilar var brachyclada
  • Opuntia basilar var longiareolata
  • Opuntia basilar var treleasei
  • Opuntia echios var barringtonensis
  • Opuntia echios var echios
  • Opuntia echios var gigantea
  • Opuntia inermis var echios
  • Opuntia echios var zacana
  • Opuntia engelmannii Opuntia engelmannii var Cuija
  • Opuntia engelmannii var engelmannii
  • Opuntia engelmannii var flavispina
  • Opuntia engelmannii var flexospina
  • Opuntia engelmannii var lindheimeri
  • Opuntia engelmannii var linguiformis
  • Opuntia galapageia var galapageia
  • Opuntia galapageia macrocarpa var
  • Opuntia galapageia var profusa
  • Opuntia macrorhiza var macrorhiza
  • Opuntia macrorhiza var pottsii
  • Opuntia megasperma megasperma var
  • Opuntia megasperma var mesophytica
  • Opuntia megasperma var orientalis
  • Opuntia parviclada
  • Opuntia penicilligera
  • Opuntia pennellii
  • Opuntia phaeacantha
  • Opuntia pilifera
  • Opuntia pinkavae
  • Opuntia pittieri
  • Opuntia pituitosa
  • Opuntia polyacantha Opuntia polyacantha var polyacantha
  • Opuntia arenaria var polyacantha
  • Opuntia erinacea var polyacantha
  • Opuntia polyacantha var hystricina
  • Opuntia polyacantha var nicholii
  • Opuntia sulphurea subsp. sulphurea
  • Opuntia sulphurea subsp. brachyacantha
  • Opuntia sulphurea subsp. spinibarbis
  • Opuntia viridirubra subsp. viridirubra
  • Opuntia viridirubra subsp. rubrogemmia
  • Opuntia vitelliniflora subsp. vitelliniflora
  • Opuntia vitelliniflora subsp. interjecta

In addition, the following natural hybrids are known:

  • Opuntia × aequatorialis Britton & Rose per sp. The natural hexaploid hybrids between Opuntia Opuntia pubescens and soederstromiana is used in Ecuador in the province of Chimborazo.
  • Opuntia × alta Griffiths per sp. The natural hybrid between Opuntia engelmannii Opuntia stricta and is distributed in the United States in Texas.
  • Opuntia × andersonii H.M.Hern. , Gómez- Hin. & Bárcenas The natural hybrid between Opuntia engelmannii Opuntia microdasys and is widespread in Mexico in southern Tamaulipas and northern San Luis Potosí.
  • Opuntia × bakeri Madsen per sp. Is probably a natural hybrid between monoploid Opuntia Opuntia pubescens and soederstromiana and is used in Ecuador in the province of Pichincha.
  • Opuntia × columbiana Griffiths per sp. The natural hybrid between Opuntia fragilis Opuntia and polyacantha var polyacantha is in the northwest of the United States spread in the state of Washington.
  • Opuntia × cubensis Britton & Rose per sp. The natural hybrid between Opuntia Opuntia militaris and triacantha is common in the Caribbean.
  • Opuntia × curvospina Griffiths per sp. The natural hybrid between Opuntia Opuntia phaeacantha chlorotica and is common in the southwest of the United States in the states of California and Nevada.
  • Opuntia × edwardsii V.E.Grant & K.A.Grant per. sp. The natural hybrid between Opuntia engelmannii Opuntia and macrorhiza is widespread in the southern United States in Texas.
  • Opuntia × lucayana Britton per sp. The natural hybrid between Opuntia dillenii and Consolea nashii is widespread in the Bahamas
  • Opuntia × occidentalis Engelm. & J.M.Bigelow per sp. The natural hybrid between Opuntia engelmannii Opuntia and phaeacantha is in the southwest of the United States spread to the south of the state of California as well as in northwestern Mexico in the state of Baja California.
  • Opuntia × rooneyi M.P.Griff. per sp. The natural hybrid between Opuntia Opuntia aureispina and macrocentra is in the south of the United States spread in Brewster County Texas.
  • Opuntia × spinosibacca M.S.Anthony per sp. The natural hybrid between Opuntia Opuntia aureispina and phaeacantha is in the south of the United States spread in Big Bend National Park in West Texas. An English common name is " Spiny - Fruited Prickly Pear ".
  • Opuntia × vaseyi ( JMCoult. ) Britton & Rose per sp. The natural hybrid between Opuntia littoralis Opuntia and phaeacantha is in the southwest of the United States spread in southern California. English common names are " Apricot Prickly Pear ", " Golden Prickly Pear " and " Sprawling Prickly Pear "
  • Opuntia × wootonii Griffiths per sp. The natural hybrid between Opuntia engelmannii Opuntia and phaeacantha is in the south of the United States spread in the state of New Mexico.

Synonyms of the genus Nopalea are Salm- Dyck, Phyllarthus Neck. ex M.Gómez. Platyopuntia Fric, Fric Chaffeyopuntia, Clavarioidia Fric & Schelle, Clavatopuntia Fric & Schelle, Salmiopuntia Fric, Fric & Schelle Subulatopuntia, Parviopuntia Soulaire, Plutonopuntia PVHeath and Salmonopuntia PVHeath.

Etymology and symbols

Etymology

In chapter 12 of the first book of De historia plantarum libri decem Theophrastus described by Eresus a plant that near the Greek city of Opus in the ancient region of Locris Opuntia, in what is now Fthiotida Prefecture, grew. About two hundred years later Pliny the Elder:

" Circa Opuntem herba est etiam homini dulcis, mirumque e folio eius radicem fieri ac sic eam nasci. "

" To Opunt grows the herb Opuntia, which is a lovely edible to humans. It is strange that the leaves take root, and that the plant is propagated in this way. "

When mentioned by Theophrastus and Pliny plant did not constitute a cactus plant. Joseph Pitton de Tournefort related to the name Opuntia for 1700, drawn up by him genus, since the Opuntientriebe often mistakenly referred to as "leaves" have the ability to take root as soon as they are laid on the ground.

Symbolism

Opuntia are closely associated with the founding of Tenochtitlan (city of stone cactus ) by the Aztecs, who settled in accordance with a prophecy after their exodus from Aztlan, where an eagle sitting on a Opuntia and fights with a snake. In the coat of arms of Mexico to this legend reflects today.

In Malta, naturalized Opuntia ficus -indica is widespread and is used for making Bajtra, a liqueur used. The importance of this Opuntia meant that it was from 1975 to 1988 part of the Maltese Coat of Arms.

Botanical history

Numerous Aztekencodices include representations of Opuntia and other cacti and succulents. In 1552 Martin de la Cruz and Juan Badiano compiled Codex Badianus example, a detailed colored drawing a designated as Tlatocnochtli Opuntia contain. In addition to the 13 listed varieties, they gave to even a formulation for the treatment of burns, as a component contained a Opuntiensaft. Bernardino de Sahagúns reported in his 1569 finished Florentine Codex also about the cultivation and use of Opuntia by the Aztecs.

The first Opuntia probably came shortly after the discovery of America to Europe. The earliest European images of cacti can be found in Gonzalo Fernández de Oviedo's Historia General y Natural de las Indias, Islas y Tierra Firme del Mar Océano 1535. He described in the use of Opuntia for wine-making and dye extraction. Giovan Battista Ramusio collection of travelogues Delle Navigationi e Viaggi (Venice 1556 ) also contains the image of a Opuntia. In his comments on Pedanios Dioscorides De Materia Medica Pietro Andrea Mattioli 1558 referred to the medical use of Opuntia. Matthias de L' Obel mentioned in 1571 and Pierre Pena in their description of the " Indian fig Tuna " that the plant in Spain, France, Italy would grow and would be cultivated in Belgium by pharmacists. Francisco Hernández, of the Viceroyalty of New Spain explored for seven years from 1570 on behalf of the Spanish King Philip II, already distinguished six types of Nochtlis ( Tunas ): Iztacnochtli that was the Spaniards as " Indian fig " ( higuera de las Indias ) known, Coznochtli, Tlatonochtli, Tlapalnochtli, Tzapnochtli and Zacanochtli.

The name Opuntia was first used in 1700 by Joseph Pitton de Tournefort for a plant genus. In Institutiones Rei Herbariae he led after a brief generic diagnosis on a total of 11 species. When Carl Linnaeus in 1753 for his work Species Plantarum edited the cactus, he rejected the old, established generic names Cereus, Melocactus, Opuntia and Pereskia and led all cacti under the generic name of Cactus, including the Opuntia Opuntia cochenillifera ( Cactus cochenillifer ), Opuntia curassavica ( curassavicus Cactus ) Opuntia ficus- indica ( Cactus opuntia ficus indica and Cactus ) and Opuntia tuna ( cactus tuna ). Only a year later Philip Miller led the generic name Opuntia again. Miller used for his 14 species not yet introduced by Linnaeus binomial nomenclature, but before the usual descriptive Latin phrases. So Opuntia ficus- indica, for example, with the phrase Opuntia articulis ovato - oblongis, spinis setaceis ( Opuntia with elongated oval links and bristly spines ) have been described. It was not until 1768 led Miller binomials in his drive.

Georg Engelmann was subdivided in 1856 in his description of the genus Opuntia 50 U.S. for the first time in the subgenera Stenopuntia, Platopuntia, Cylindropuntia. In the first overall scientific processing of cactus plants that Karl Moritz Schumann published at the end of the 19 century, 131 Opuntia species are already listed. As Nathaniel Lord Britton and Joseph Nelson Rose published in 1919 the first volume of The Cactaceae, included in its opinion, the genus is already at least 250 species. From the literature, but they more than 900 names were known, which should be among the cacti, however, were not described or inadequate. When they put their processing for some types of new genera Opuntia on, or accepted these again ( Nopalea, Maihuenia, Pereskiopsis ). Other genera ( Tephrocactus, Consolea ) were given to them part of Opuntia. Curt Backeberg split their 1958 as well as later Friedrich Ritter (1980 ) on the extensive genus of cacti in other genera.

Began in 1958 by Gordon Douglas Rowley with the inclusion of different individual species in the cacti, the opposite trend towards a large collection genus, which lasted until 1999. Roberto Kiesling (* 1941) presented in 1984 a proposal to outsource different types back from the Opuntia in their own genres. From the Cactaceae Working Party of the International Organization for Sukkulentenforschung these considerations were rejected for a long time. 2001 confirmed research of DNA and the morphology of seeds, pollen and thorns that such a broad genus concept is polyphyletic and can not be maintained.

Use

Use as a coloring agent

Karminerzeugende Cochenillenschildläuse

Since about 1100, the Aztecs built on large plantations " Nochtli " plants to ( Opuntia cochenillifera ) to produce the dye carmine. Their heads wore bright crimson robes with which they impressed the Spaniards. The preparation thus dyed textiles, however, already known from the much older Paracas culture.

The Spanish conquerors recognized the commercial value of the dye quickly. They kept the secret of its production strictly and successfully over many decades. It was Nicolas Hartsoeker who first published a drawn enlarged view of a Cochenilleschildlaus in Essai de Dioptrique 1694. Ten years later, Antoni van Leeuwenhoek studied those responsible for color production scale insects (especially Dactylopius coccus ) very closely and was able to finally clarify that not cacti, but it live insects are necessary for the manufacture of dyes. 1776 traveled Nicolas Joseph de Thiéry Ménonville on behalf of the French government to Mexico to spy out the details of the manufacture of dyes. He managed to run Opuntientriebe with Cochenilleschildläusen that he could reproduce successfully in Haiti Port-au -Prince.

As host plants for the Cochenilleschildläuse also more suitable Opuntienarten. In the Canary Islands large plantations of Opuntia ficus- indica, which are used for the manufacture of dyes popular today. At 1 kilogram to produce carmine, 140,000 insects are necessary. The insects are killed by heat and then dried. Although derived from the insect dye has lost through the establishment of equivalent synthetic dyes in importance, it is still produced in Mexico, Chile, the Canary Islands, and various African countries. The main part is made in Peru. With naturally produced Carmine example, food and beverage and cosmetic products are colored.

Opuntienfrüchte

The fruits of Opuntia schumannii be used in the north of South America to color ice cream and fruit juices. With the fruits of Opuntia dillenii ropes made ​​of hemp fibers are dyed red. Opuntia Opuntia humifusa polyacantha and were used by the Absarokee, the Dakota and Pawnee as a mordant.

Use as feed

During the Spanish colonial rule was on a larger scale livestock, especially sheep and goats, introduced to Mexico. In the arid regions of the animals were often supplied by the farmers only poorly with water and grass and roamed around freely, therefore, to provide for themselves. It was observed how the cattle fed, among other things of Opuntia. In order to provide the animals in times of drought, cacti were eventually cultivated by farmers in Mexico since the 19th century specifically as animal feed.

As CAM plants can produce three about five times more biomass than C3 plants and sometimes more than C4 plants Opuntia from the available in the arid and semi-arid areas of precipitation. Cacti have a high calorific value and are rich in water, vitamins, carbohydrates and calcium. The disadvantage is the lack of proteins, which must be balanced by an appropriate additional feeding, for example, with straw.

End of the 20th century were grown worldwide to about 900,000 hectares opuntias for use as animal feed. In comparison, the line used for the recovery of Opuntia fruit acreage amounted to only about 100,000 hectares. For the cultivation mainly forms of Opuntia ficus -indica are used. In addition to Mexico, among other Opuntia in Ethiopia, Brazil, Chile, South Africa and the United States are used for agriculture. The importance of Opuntia as feed will win, according to the Food and Agriculture Organization of the United Nations in the future more and more important.

Other Terms

The young and still soft drive sections ( Nopalito ) are eaten as a vegetable. The fruit ( tuna) are consumed fresh. They are used for the preparation of pharmaceutical and cosmetic products, and used in the cure of diseases such as diabetes, atherosclerosis, hypercholesterolemia, heart disease, obesity, cancer and ulcers. The fruits of Opuntia ficus -indica are edible and can be eaten raw peeled or processed into juice.

In the manual harvest of the shoots and fruits of Opuntia the thereon glochids can cause dermatitis, which is often called Sabra dermatitis.

Opuntia as a weed

As invasive neophytes some Opuntienarten common example in the Mediterranean region, Australia, India, South Africa and Hawaii so strong that they were there regarded as weeds and adequately controlled. Because of the pronounced in the Opuntia ability to reproduce vegetatively, the plants could not be easily removed by plowing. Initial attempts at biological control of weeds have been made in northern India in 1863. The original mistakenly imported from Brazil 1795 Schildlausart Dactylopius ceylonicus should actually serve to produce Cochinelle red. They later proved to be an effective remedy for the introduced from South America Opuntia vulgaris. The successful use of this scale insect is considered the first documented example of a biological weed control.

Opuntia stricta served in 1832 in Australia, about 125 kilometers northwest of Sydney, as a hedge for the local vineyards and seven years later was planted as an ornamental plant in Sydney. The plants overgrown but quickly became a nuisance. To 1883, the problem was so great that the Australian government passed a law to combat it. In 1914, Opuntia ficus- indica has been introduced as a potential food plant, the problem got worse still. Mainly in Queensland about 25 million hectares were planted around 1925 of Opuntia and could no longer be used for agriculture. From 1920 to 1935 studied entomologist in the United States, Mexico and Argentina for natural enemies of Opuntia. Of 150 species found were introduced 52 to Australia. Twelve were able to establish successful there. The 1925 introduced larvae of cactus moth ( Cactoblastis cactorum ) destroyed in less than 10 years, about 90 percent of the stock of Opuntia.

In South Africa 1932, to combat the thorny form of Opuntia ficus-indica, the scale insect Dactylopius opuntiae, Metamasius spinolae from the weevil family and Cactoblastis cactorum introduced. Unlike in Australia here Dactylopius opuntiae proved to be most effective. Introduced to Hawaii Opuntia megacantha was particular Parker Ranch becomes a problem. In the 1940s also Dactylopius opuntiae and Cactoblastis cactorum were used to fighting.

Cactoblastis cactorum was found in 1989 for the first time in the Florida Keys. From there, he continues to spread and threatened today as the pest Opuntienkulturen in the southern United States and Mexico.

To weed pest is Opuntia can also develop in their natural range. In South Texas Farmer plowing large areas of arable land to cultivate exotic grasses. However, They made it engelmannii also for mass vegetative propagation of Opuntia.

Endangering

In Appendix I of the CITES Convention no Opuntia are included. In the Red List of Threatened Species IUCN contrast, ten species are listed with different threat status. Two species, Opuntia Opuntia saxicola chaffeyi and are considered threatened with extinction. When threatened or being at risk are endemic to the Galapagos Islands species Opuntia echios, galapageia Opuntia, Opuntia helleri and Opuntia insularis. This level of danger also applies to megarhiza Opuntia, Opuntia Opuntia megasperma and pachyrrhiza. The only unthreatened out of ten on the Red List Opuntienarten is Opuntia monacantha.

Evidence

Pictures of Opuntia

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