Opuntia

Opuntia is a genus in the cactus family, Cactaceae.

Currently, only prickly pears (also known as nopal or nopales, from the Nahuatl word nōpalli for the pads, or nostle, from the Nahuatl word nōchtli for the fruit; see below) are included in this genus of about 200 species distributed throughout most of the Americas. Chollas are now separated into the genus Cylindropuntia, which some still consider a subgenus of Opuntia. Austrocylindropuntia, Corynopuntia and Micropuntia are also often included in the present genus, but like Cylindropuntia they seem rather well distinct. Brasiliopuntia and Miqueliopuntia are closer relatives of Opuntia.

The most commonly culinary species is the Indian Fig Opuntia (O. ficus-indica). Most culinary uses of the term 'prickly pear' refer to this species.

Description

Prickly pear cacti typically grow with flat, rounded platyclades that are armed with two kinds of spines; large, smooth, fixed spines and small, hairlike spines called glochids that easily penetrate skin and detach from the plant. Many types of prickly pears grow into dense, tangled structures.

Prickly pear species are found in abundance in the West and Southwest of the United States and throughout much of Mexico. Prickly pears are also the only types of cactus natively found to grow in the eastern United States. They are also found in the Mediterranean region of southern Europe, especially on the island nation of Malta where they grow on cactus found all over the island. Opuntia are the most cold-tolerant of the lowland cacti, extending into western and southern Canada; one subspecies, Opuntia fragilis var. fragilis, has been found growing along the Beatton River in central British Columbia, southwest of Cecil Lake at 56° 17’ N latitude and 120° 39’ W longitude.

Charles Darwin was the first to note that these cacti have thigmotactic anthers: when the anthers are touched, they curl over, depositing their pollen. This movement can be seen by gently poking the anthers of an open Opuntia flower. The same trait has evolved convergently in other cacti (e.g. Lophophora).

Chollas

Chollas, now recognized to belong into a rather distinct genus Cylindropuntia, are distinguished by having cylindrical, rather than flattened, stem segments with the large barbed spines. The stem joints of several species, notably the jumping cholla (Cylindropuntia fulgida), are very brittle on young stems, readily breaking off when the barbed spines stick to clothing or animal skin as a method of vegetative reproduction. The barbed spines can remain embedded in the skin, causing significant discomfort and sometimes injury.

Life Cycle

Prickly Pear Leaf Cycle

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Opuntia and humans

As food

The fruit of prickly pears, commonly called cactus figs, Indian fig or tuna, is edible, although it has to be peeled carefully to remove the small spines on the outer skin before consumption. If the outer layer is not properly removed, glochids can be ingested causing discomfort of the throat, lips, and tongue as the small spines are easily lodged in the skin. Native Americans like the Tequesta would roll the fruit around in suitable medium (e.g. grit) to "sand" off the glochids. Today, parthenocarpic (seedless) cultivars are also available.

Cactus figs are often used to make candies and jelly and a refreshing drink.

Opuntia ficus-indica has been introduced to Europe and flourishes in areas with a suitable climate, such as the south of France, southern Italy, Sicily where they are referred to as fichi d'India or ficurinnia (Indian figs), along the Struma River in Bulgaria, in Southern Portugal and Madeira where they are called tabaibo or "Indian figs", and eastern and southern Spain as well as Gibraltar where they are known as chumbo or higo chumbo ("chumbo fig"). In Greece it grows in such places as Corfu and its figs are known as frangosyka (French figs) or pavlosyka (Paul's figs). The figs are also grown in Cyprus, where they are known as papoutsosyka (shoe figs). The prickly pear also grows widely on the islands of Malta where it is enjoyed by the Maltese as a typical summer fruit (known as bajtar tax-xewk, literally 'spiny figs') as well as being used to make the popular liqueur known as Bajtra. The prickly pear is so commonly found in the Maltese islands that it is often used as a dividing wall between many of Malta's characteristic terraced fields in place of the usual rubble walls. The prickly pear was introduced to Eritrea during the period of Italian colonisation between 1890 and 1940. It is locally known there as Beles and is abundant during the months of late summer and early autumn (late July - September). The Beles from the holy monastery of 'Bizen is said to be particularly sweet and juicy.

In Egypt, Saudi Arabia and other parts of the Middle East, prickly pears of the yellow and orange varieties are grown by the side or farms, beside railway tracks and other otherwise non-cultivable land. It is sold in summer by street vendors and is considered a nice refreshing fruit for that season.

Tungi is the local St. Helenian name for cactus pears. The plants (Indian Fig Opuntia) were originally brought to the island by the colonial ivory traders from East Africa in the 1850s. Tungi cactus now grows wild and organically in the dry coastal regions of the island. Three principal cultivars of tungi grow on the island: the 'English' with yellow fruit; the 'Maderia' with large red fruit; and the small firm 'Spiny Red'.

The young stem segments, usually called nopales, are also edible in most species of Opuntia. They are commonly used in Mexican cuisine in dishes such as huevos con nopales (eggs with nopal), or tacos de nopales. Nopales are also an important ingredient in New Mexican cuisine.

Medical uses

Most species of Opuntia contain a range of alkaloids in ample quantities, notably substituted phenethylamines. While the mere presence of such compounds has been confirmed in many species without further details, they have been studied more thoroughly in others. Identified compounds of medical significance include 3-methoxytyramine, candicine, hordenine, N-methyltyramine and tyramine.

The stem of certain Opuntia spp. can be used to treat type II diabetes, diarrhea, and stomach ache. However, usefulness of Opuntia in treating diabetes is not at all resolved. Although some researchers have shown a blood glucose-lowering effect of O. streptacantha, another study of three other species of Opuntia (O. lasiacantha, O. velutina, and O. macrocentra) showed no such effect. Yet another study, on O. megacantha, raised concern about toxic effects on the kidney.

It may be that certain species are effective and useful in diabetes while others are not but this needs to be clarified with further research before recommending its use. Furthermore, when buying nopal in the market, it is impossible to know which species one is buying and therefore whether or not it is useful in treating diabetes.

Indian Fig Opuntia (and probably others) might have a reducing effect on alcohol hangover by inhibiting the production of inflammatory mediators. Studies have yielded differing results, with some studies witnessing significant reductions in nausea, dry mouth, and loss of appetite as well as less risk of a severe hangover, while others witnessing no compelling evidence for effects on alcohol hangover.

The gel-like sap of prickly pears can be used as hair conditioner.

In Mexico and the Southwest, its pulp and juice have been used to treat a numerous amount of maladies such as wounds and inflammations of the digestive and urinary tracts.

As an intoxicant

At least two commercially important distilled spirits are produced from Opuntia fruit. In Malta, the pink herbal Bajtra Liqueur is made from Opuntia. A St. Helenian distillery produces the clear, more potent Tungi Spirit from Indian Fig Opuntia cv. 'English' and 'Madeira'.

Opuntia is also added sometimes to the entheogenic drink Ayahuasca. Psychoactive compounds and derivates thereof have been confirmed in some species. These include 3,4-DMPEA, 4-hydroxy-3,5-DMPEA, and mescaline.

In dye production

Dactylopius coccus is a scale insect, from which the cochineal dye is derived. D. coccus itself is native to tropical and subtropical South America and Mexico. This type of insect, a primarily sessile parasite, lives on cacti from the genus Opuntia, feeding on moisture and nutrients in the cactus sap. The insect produces carminic acid which deters predation by other insects. The carminic acid can be extracted from the insect's body and eggs to make the red dye.

Cochineal is primarily used as a red food colouring and for cosmetics. The cochineal dye was used by the Aztec and Maya peoples of Central and North America. Produced almost exclusively in Oaxaca, Mexico by indigenous producers, cochineal became Mexico's second most valued export after silver. The dyestuff was consumed throughout Europe and was so highly valued that its price was regularly quoted on the London and Amsterdam Commodity Exchanges.

In present times, the highest production of cochineal is by Peru, the Canary Islands and Chile. Current health concerns over artificial food additives have renewed the popularity of cochineal dyes, and the increased demand is making cultivation of the insect an attractive opportunity in other regions, such as in Mexico where cochineal production had declined again due to the scale insect having numerous natural enemies.

Apart from cochineal, the red dye betanin can be extracted from some Opuntia plants themselves.

In culture

The coat of arms of Mexico depicts a Mexican golden eagle, perched upon an Opuntia cactus, devouring a snake. According to the official history of Mexico, the coat of arms is inspired by an Aztec legend regarding the founding of Tenochtitlan. The Aztecs, then a nomadic tribe, were wandering throughout Mexico in search of a divine sign that would indicate the precise spot upon which they were to build their capital. Their god Huitzilopochtli had commanded them to find an eagle devouring a snake, perched atop a cactus that grew on a rock submerged in a lake. After two hundred years of wandering, they found the promised sign on a small island in the swampy Lake Texcoco. It was there they founded their new capital, Tenochtitlan. The cactus (Opuntia ficus-indica; Nahuatl: tenochtli), full of fruits, is the symbol for the island of Tenochtitlan.

The 1975-1988 version of the coat of arms of Malta also featured an opuntia.

In Israel, the cactus fig is called tzabar (צבר). This is the origin of the slang term sabra for a native-born Israeli Jew.

The cactus lends its name to a song by British Jazz/Classical group Portico Quartet.

Ecology

Opuntia spreads into large clonal colonies, which contributes to the fact that it is considered a noxious weed in some places.

Prickly pears (mostly Opuntia tomentosa) were imported into Australia in the 19th century for use as a natural agricultural fence and in an attempt to establish a cochineal dye industry. They quickly became a widespread invasive weed, rendering 40,000 km² of farming land unproductive. The moth Cactoblastis cactorum from South America, whose larvae eat prickly pear, was introduced in 1925 and almost wiped out the population. This case is sometimes cited as an example of successful biological pest control.

The same moth, introduced accidentally further north of its native range into southern North America, is causing serious damage to some native species in that area.

Other animals that eat Opuntia include the Prickly pear island snail and Cyclura rock iguanas. The fruit are relished by many aridland animals, chiefly birds, which thus help distribute the seeds. Opuntia pathogens include the sac fungus Colletotrichum coccodes and Sammons' Opuntia virus. The ant Crematogaster opuntiae and the spider Theridion opuntia are named for their association with prickly pear cacti.

Selected species

Opuntia hybridizes readily between species. Perhaps only oaks do so as readily. This can make classification difficult. Also, not all species listed here may actually belong into this genus.

• Opuntia aciculata
• Opuntia anacantha
• Opuntia atrispina
• Opuntia auberi
• Opuntia aurantiaca
• Opuntia basilaris – Beavertail cactus
• Opuntia boldinghii
• Opuntia chaffeyi
• Opuntia chlorotica – Pancake Prickly Pear; native to southwest USA and the Sonoran and Mojave deserts.
• Opuntia clavata
• Opuntia cochenillifera
• Opuntia comonduensis
• Opuntia compressa
• Opuntia curvospina
• Opuntia decumana
• Opuntia decumbens – Nopal de Culebra
• Opuntia dejecta
• ''Opuntia echios
• Opuntia echios var. gigantea – Galápagos prickly pear. Galápagos Islands.
• Opuntia elata
• Opuntia elatior Mill. – syn. O. bergeriana
• Opuntia engelmannii – Engelmann's Prickly Pear, Cow's-tongue Prickly Pear, Desert Prickly Pear, Discus Prickly Pear, Texas Prickly Pear, calico cactus
• Opuntia erinacea
• Opuntia exaltata
• Opuntia excelsa
• Opuntia ficus-barbarica
• Opuntia ficus-indica – Indian Fig Opuntia
• Opuntia fragilis – Little Prickly Pear, brittle cactus. Found in the Great Plains and as far west as British Columbia.
• Opuntia galapageia
• Opuntia gosseliniana – Violet Prickly Pear
• Opuntia gosseliniana var. santa-rita – Santa Rita Prickly Pear
• Opuntia helleri
• Opuntia hickenii
• Opuntia humifusa – Eastern Prickly Pear (sometimes included in O. compressa)
• Opuntia hyptiacantha
• Opuntia inamoema K. Schum. – quipá
• Opuntia insularis
• Opuntia invicta
• Opuntia jamaicensis
• Opuntia laevis
• Opuntia lasiacantha
• Opuntia leucotricha – Arborescent Prickly Pear, Aaron's beard cactus, semaphore cactus, Duraznillo blanco, Nopal blanco
• Opuntia lindheimeri
• Opuntia littoralis – Sprawling Prickly Pear
• Opuntia macbridei
• Opuntia macrocentra – Black-spine Prickly Pear, Purple Prickly Pear. Found in southwest USA and northern Mexico.
• Opuntia macrorhiza – Plains Prickly Pear. Found throughout the Great Plains except for the northernmost areas (not found in North Dakota), and extending sporadically eastward as far as Kentucky. Syn. O. leptocarpa MacKensen, O. tenuispina Engelm., O. tortispina Engelm. & Bigelow
• Opuntia maldonandensis
• Opuntia maxima
• Opuntia megacantha
• Opuntia megarrhiza
• Opuntia megasperma
• Opuntia microdasys – Bunny ears cactus, Polka-dot cactus
• Opuntia monacantha – Common Prickly Pear
• Opuntia oricola
• Opuntia ovata
• Opuntia pachypus
• Opuntia pachyrrhiza
• Opuntia phaeacantha – Tulip Prickly Pear. Includes Plateau Prickly Pear, Brown-spined Prickly Pear, Mojave Prickly Pear, Kingman Prickly Pear.
• Opuntia pinkavae – Pinkava's Prickly Pear
• Opuntia polyacantha – Panhandle Prickly Pear. Found in the Great Plains, Great Basin, Mojave Desert, Colorado Plateau, and the Rocky Mountains. Syn. O. rhodantha K.Schum.
• Opuntia polyacantha var. arenaria (syn. O. erinacea)
• Opuntia pubescens (syn. O. pascoensis Britton & Rose)
• Opuntia pusilla – Creeping cactus. Syn. O. drummondii Graham
• Opuntia rastrera
• Opuntia repens

• Opuntia robusta
• Opuntia rufida (sometimes included in O. microdasys)
• Opuntia saxicola
• Opuntia schumannii
• Opuntia soehrensii
• Opuntia stenopetala (syn. O. riviereana Backeb.)
• Opuntia streptacantha
• Opuntia stricta – Erect Prickly Pear, Spineless Prickly Pear, Coastal Prickly Pear
• Opuntia subulata – found in South America
• Opuntia sulphurea
• Opuntia taylori
• Opuntia tehuantepecana – Nopal de Caballo
• Opuntia tomentosa – Woollyjoint Prickly Pear
• Opuntia triacantha
• Opuntia tuna
• Opuntia velutina
• Opuntia violacea

Formerly in Opuntia

• Austrocylindropuntia
• Brasiliopuntia
• Corynopuntia
• Cylindropuntia
• Disocactus phyllanthoides (as Opuntia speciosa)
• Micropuntia
• Miqueliopuntia

Footnotes

References

• (1995): The bug that changed history. Boatman's Quarterly Rreview 8(2). HTML fulltext
• (2000): Effects of Opuntia megacantha on blood glucose and kidney function in streptozotocin diabetic rats. Journal of Ethnopharmacology 69(3): 247-252. PMID 10722207 (HTML abstract)
• (2002): Taxonomy, distribution, rarity status and uses of Canadian Cacti. Haseltonia 9: 17-25 PDF abstract
• (1983): Effects of nopal (Opuntia sp.) on serum lipids, glycemia and body weight. Archivos de investigacion medica 14(2): 117-125. PMID 6314922 [Article in English, Spanish]
• (1995): Ayahuasca Additive Plants In: Ayahuasca Analogues: Pangaean Entheogens.
• (2005): Interventions for preventing or treating alcohol hangover: systematic review of randomised controlled trials. Brit. Med. J. 331(7531): 1515-1518. PMID 16373736 PDF fulltext
• (1988): Natural Enemies of Cochineal (Dactylopius coccus Costa): Importance in Mexico. Journal of the Professional Association for Cactus Development 3: 43-49. PDF fulltext
• (1998): Glycemic Effects of Various Species of Nopal (Opuntia sp.) in Type 2 Diabetes Mellitus. Texas Journal of Rural Health 16(1): 68-76.
• (1997): Visionary Cactus Guide: Opunita [sic]. Retrieved 2007-OCT-15.
• (2004): Effect of Opuntia ficus indica [sic] on Symptoms of the Alcohol Hangover. Arch. Intern. Med. 164(12): 1334-1340. PDF fulltext

External links

• Opuntiads of the USA
• Arizona Salvage Restricted Protected Native Plants (AZ Dept. of Agriculture)
• Prickly Pear photograph album 1926-1933 digitised and held by State Library of Queensland.
• Article in Weeds.org with information about the prickly pear in Australia