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  • Banana

    banana is an elongated, edible fruit – botanically a berry[1] – produced by several kinds of large treelike herbaceous flowering plants in the genus Musa. In some countries, cooking bananas are called plantains, distinguishing them from dessert bananas. The fruit is variable in size, color and firmness, but is usually elongated and curved, with soft flesh rich in starch covered with a peel, which may have a variety of colors when ripe. It grows upward in clusters near the top of the plant. Almost all modern edible seedless (parthenocarp) cultivated bananas come from two wild species – Musa acuminata and Musa balbisiana, or hybrids of them.

    Musa species are native to tropical Indomalaya and Australia; they were probably domesticated in New Guinea. They are grown in 135 countries, primarily for their fruit, and to a lesser extent to make banana paper and textiles, while some are grown as ornamental plants. The world’s largest producers of bananas in 2022 were India and China, which together accounted for approximately 26% of total production. Bananas are eaten raw or cooked in recipes varying from curries to banana chipsfritters, fruit preserves, or simply baked or steamed.

    Worldwide, there is no sharp distinction between dessert “bananas” and cooking “plantains”: this distinction works well enough in the Americas and Europe, but it breaks down in Southeast Asia where many more kinds of bananas are grown and eaten. The term “banana” is applied also to other members of the genus Musa, such as the scarlet banana (Musa coccinea), the pink banana (Musa velutina), and the Fe’i bananas. Members of the genus Ensete, such as the snow banana (Ensete glaucum) and the economically important false banana (Ensete ventricosum) of Africa are sometimes included. Both genera are in the banana family, Musaceae.

    Banana plantations are subject to damage by parasitic nematodes and insect pests, and to fungal and bacterial diseases, one of the most serious being Panama disease which is caused by a Fusarium fungus. This and black sigatoka threaten the production of Cavendish bananas, the main kind eaten in the Western world, which is a triploid Musa acuminata. Plant breeders are seeking new varieties, but these are difficult to breed given that commercial varieties are seedless. To enable future breeding, banana germplasm is conserved in multiple gene banks around the world.

    Description

    The banana plant is the largest herbaceous flowering plant.[2] All the above-ground parts of a banana plant grow from a structure called a corm.[3] Plants are normally tall and fairly sturdy with a treelike appearance, but what appears to be a trunk is actually a pseudostem composed of multiple leaf-stalks (petioles). Bananas grow in a wide variety of soils, as long as it is at least 60 centimetres (2.0 ft) deep, has good drainage and is not compacted.[4] They are fast-growing plants, with a growth rate of up to 1.6 metres (5.2 ft) per day.[5]

    The leaves of banana plants are composed of a stalk (petiole) and a blade (lamina). The base of the petiole widens to form a sheath; the tightly packed sheaths make up the pseudostem, which is all that supports the plant. The edges of the sheath meet when it is first produced, making it tubular. As new growth occurs in the centre of the pseudostem, the edges are forced apart.[3] Cultivated banana plants vary in height depending on the variety and growing conditions. Most are around 5 m (16 ft) tall, with a range from ‘Dwarf Cavendish‘ plants at around 3 m (10 ft) to ‘Gros Michel‘ at 7 m (23 ft) or more.[6][7] Leaves are spirally arranged and may grow 2.7 metres (8.9 ft) long and 60 cm (2.0 ft) wide.[1] When a banana plant is mature, the corm stops producing new leaves and begins to form a flower spike or inflorescence. A stem develops which grows up inside the pseudostem, carrying the immature inflorescence until eventually it emerges at the top.[3] Each pseudostem normally produces a single inflorescence, also known as the “banana heart”. After fruiting, the pseudostem dies, but offshoots will normally have developed from the base, so that the plant as a whole is perennial.[8] The inflorescence contains many petal-like bracts between rows of flowers. The female flowers (which can develop into fruit) appear in rows further up the stem (closer to the leaves) from the rows of male flowers. The ovary is inferior, meaning that the tiny petals and other flower parts appear at the tip of the ovary.[9]

    The banana fruits develop from the banana heart, in a large hanging cluster called a bunch, made up of around nine tiers called hands, with up to 20 fruits to a hand. A bunch can weigh 22–65 kilograms (49–143 lb).[10] The stalk ends of the fruits connect up to the rachis part of the inflorescence. Opposite the stalk end, is the blossom end, where the remnants of the flower deviate the texture from the rest of the flesh inside the peel.

    The fruit has been described as a “leathery berry”.[11] There is a protective outer layer (a peel or skin) with numerous long, thin strings (Vascular bundles), which run lengthwise between the skin and the edible inner white flesh. The peel is less palatable and usually discarded after peeling the fruit, optimally done from the blossom end, but often started from the stalk end. The inner part of the common yellow dessert variety can be split lengthwise into three sections that correspond to the inner portions of the three carpels by manually deforming the unopened fruit.[12] In cultivated varieties, fertile seeds are usually absent.[13][14]

    • A corm, about 25 cm (10 in) across
    • Young plant
    • Female flowers have petals at the tip of the ovary
    • ‘Tree’ showing fruit and inflorescence
    • Single row planting
    • Inflorescence, partially opened

    Evolution

    Phylogeny

    A 2011 phylogenomic analysis using nuclear genes indicates the phylogeny of some representatives of the Musaceae family. Major edible kinds of banana are shown in boldface.[15]

    MusaceaeMusaClade IMusa acuminata ssp. burmannicaBanana, S. India to CambodiaMusa ornata, Flowering banana of Southeast AsiaMusa acuminata ssp. zebrinaBlood banana of SumatraMusa mannii, a wild banana of Arunachal Pradesh, IndiaMusa balbisianaPlantain of South, East, and Southeast AsiaClade IIMusa x troglodytarumFe’i banana of French PolynesiaMusa maclayi of Papua New Guinea and Solomon IslandsMusa textilis, Abacá or Manila hemp of the PhilippinesMusa beccarii, a wild banana of SabahMusa coccinea, Scarlet banana of China and VietnamMusella lasiocarpa, Golden lotus banana of ChinaEnsete ventricosum, Enset or false banana of Africa

    Many cultivated bananas are hybrids of M. acuminata x M. balbisiana (not shown in tree).[16]

    Work by Li and colleagues in 2024 identifies three subspecies of M. acuminata, namely sspp. banksiimalaccensis, and zebrina, as contributing substantially to the BanDh, and Ze subgenomes of triploid cultivated bananas respectively.[17]

    Taxonomy

    Further information: List of banana cultivars

    Musa ‘Nendran’ cultivar, grown widely in the Indian state of Kerala

    The genus Musa was created by Carl Linnaeus in 1753.[18] The name may be derived from Antonius Musa, physician to the Emperor Augustus, or Linnaeus may have adapted the Arabic word for banana, mauz.[19] The ultimate origin of musa may be in the Trans–New Guinea languages, which have words similar to “#muku”; from there the name was borrowed into the Austronesian languages and across Asia, accompanying the cultivation of the banana as it was brought to new areas, via the Dravidian languages of India, into Arabic as a Wanderwort.[20] The word “banana” is thought to be of West African origin, possibly from the Wolof word banaana, and passed into English via Spanish or Portuguese.[21]

    Musa is the type genus in the family Musaceae. The APG III system assigns Musaceae to the order Zingiberales, part of the commelinid clade of the monocotyledonous flowering plants. Some 70 species of Musa were recognized by the World Checklist of Selected Plant Families as of January 2013;[18] several produce edible fruit, while others are cultivated as ornamentals.[22]

    The classification of cultivated bananas has long been a problematic issue for taxonomists. Linnaeus originally placed bananas into two species based only on their uses as food: Musa sapientum for dessert bananas and Musa paradisiaca for plantains. More species names were added, but this approach proved to be inadequate for the number of cultivars in the primary center of diversity of the genus, Southeast Asia. Many of these cultivars were given names that were later discovered to be synonyms.[23]

    In a series of papers published from 1947 onward, Ernest Cheesman showed that Linnaeus’s Musa sapientum and Musa paradisiaca were cultivars and descendants of two wild seed-producing species, Musa acuminata and Musa balbisiana, both first described by Luigi Aloysius Colla.[24] Cheesman recommended the abolition of Linnaeus’s species in favor of reclassifying bananas according to three morphologically distinct groups of cultivars – those primarily exhibiting the botanical characteristics of Musa balbisiana, those primarily exhibiting the botanical characteristics of Musa acuminata, and those with characteristics of both.[23] Researchers Norman Simmonds and Ken Shepherd proposed a genome-based nomenclature system in 1955. This system eliminated almost all the difficulties and inconsistencies of the earlier classification of bananas based on assigning scientific names to cultivated varieties. Despite this, the original names are still recognized by some authorities, leading to confusion.[24][25]

    The accepted scientific names for most groups of cultivated bananas are Musa acuminata Colla and Musa balbisiana Colla for the ancestral species, and Musa × paradisiaca L. for the hybrid of the two.[16]

    An unusual feature of the genetics of the banana is that chloroplast DNA is inherited maternally, while mitochondrial DNA is inherited paternally. This facilitates taxonomic study of species and subspecies relationships.[26]

    Informal classification

    In regions such as North America and Europe, Musa fruits offered for sale can be divided into small sweet “bananas” eaten raw when ripe as a dessert, and large starchy “plantains” or cooking bananas, which do not have to be ripe. Linnaeus made this distinction when naming two “species” of Musa.[27] Members of the “plantain subgroup” of banana cultivars, most important as food in West Africa and Latin America, correspond to this description, having long pointed fruit. They are described by Ploetz et al. as “true” plantains, distinct from other cooking bananas.[28]

    The cooking bananas of East Africa belong to a different group, the East African Highland bananas.[7] Further, small farmers in Colombia grow a much wider range of cultivars than large commercial plantations do,[29] and in Southeast Asia—the center of diversity for bananas, both wild and cultivated—the distinction between “bananas” and “plantains” does not work. Many bananas are used both raw and cooked. There are starchy cooking bananas which are smaller than those eaten raw. The range of colors, sizes and shapes is far wider than in those grown or sold in Africa, Europe or the Americas.[27] Southeast Asian languages do not make the distinction between “bananas” and “plantains” that is made in English. Thus both Cavendish dessert bananas and Saba cooking bananas are called pisang in Malaysia and Indonesia, kluai in Thailand and chuối in Vietnam.[30] Fe’i bananas, grown and eaten in the islands of the Pacific, are derived from a different wild species. Most Fe’i bananas are cooked, but Karat bananas, which are short and squat with bright red skins, are eaten raw.[31]

    History

    Domestication

    See also: Musa acuminataDomesticated plants and animals of Austronesia, and East African Highland bananas

    The earliest domestication of bananas (Musa spp.) was from naturally occurring parthenocarpic (seedless) individuals of Musa banksii in New Guinea.[32] These were cultivated by Papuans before the arrival of Austronesian-speakers. Numerous phytoliths of bananas have been recovered from the Kuk Swamp archaeological site and dated to around 10,000 to 6,500 BP.[33][34] Foraging humans in this area began domestication in the late Pleistocene using transplantation and early cultivation methods.[35] By the early to middle of the Holocene the process was complete.[35] From New Guinea, cultivated bananas spread westward into Island Southeast Asia. They hybridized with other (possibly independently domesticated) subspecies of Musa acuminata as well as M. balbisiana in the Philippines, northern New Guinea, and possibly Halmahera. These hybridization events produced the triploid cultivars of bananas commonly grown today.[33] The banana was one of the key crops that enabled farming to begin in Papua New Guinea.[36]

    Spread

    From Island Southeast Asia, bananas became part of the staple domesticated crops of Austronesian peoples.[33][34]

    These ancient introductions resulted in the banana subgroup now known as the true plantains, which include the East African Highland bananas and the Pacific plantains (the Iholena and Maoli-Popo’ulu subgroups). East African Highland bananas originated from banana populations introduced to Madagascar probably from the region between JavaBorneo, and New Guinea; while Pacific plantains were introduced to the Pacific Islands from either eastern New Guinea or the Bismarck Archipelago.[33]

    21st century discoveries of phytoliths in Cameroon dating to the first millennium BCE[37] triggered a debate about the date of first cultivation in Africa. There is linguistic evidence that bananas were known in East Africa or Madagascar around that time.[38] The earliest prior evidence indicates that cultivation dates to no earlier than the late 6th century AD.[39] Malagasy people colonized Madagascar from South East Asia around 600 AD onwards.[40] Glucanase and two other proteins specific to bananas were found in dental calculus from the early Iron Age (12th century BCE) Philistines in Tel Erani in the southern Levant.[41]

    Another wave of introductions later spread bananas to other parts of tropical Asia, particularly Indochina and the Indian subcontinent.[33] Some evidence suggests bananas were known to the Indus Valley civilisation from phytoliths recovered from the Kot Diji archaeological site in Pakistan.[34] Southeast Asia remains the region of primary diversity of the banana. Areas of secondary diversity are found in Africa, indicating a long history of banana cultivation there.[42]

    Arab Agricultural Revolution

    Further information: Arab Agricultural Revolution

    The banana may have been present in isolated locations elsewhere in the Middle East on the eve of Islam. The spread of Islam was followed by far-reaching diffusion. There are numerous references to it in Islamic texts (such as poems and hadiths) beginning in the 9th century. By the 10th century, the banana appeared in texts from Palestine and Egypt. From there it diffused into North Africa and Muslim Iberia during the Arab Agricultural Revolution.[43][44] An article on banana tree cultivation is included in Ibn al-‘Awwam‘s 12th-century agricultural work, Kitāb al-Filāḥa (Book on Agriculture).[45] During the Middle Ages, bananas from Granada were considered among the best in the Arab world.[44] Bananas were certainly grown in the Christian Kingdom of Cyprus by the late medieval period. Writing in 1458, the Italian traveller and writer Gabriele Capodilista wrote favourably of the extensive farm produce of the estates at Episkopi, near modern-day Limassol, including the region’s banana plantations.[46]

    Early modern spread

    Further information: Columbian exchange

    In the early modern period, bananas were encountered by European explorers during the Magellan expedition in 1521, in both Guam and the Philippines. Lacking a name for the fruit, the ship’s historian Antonio Pigafetta described them as “figs more than one palm long.”[47][48]: 130, 132  Bananas were introduced to South America by Portuguese sailors who brought them from West Africa in the 16th century.[49] Southeast Asian banana cultivars, as well as abaca grown for fibers, were introduced to North and Central America by the Spanish from the Philippines, via the Manila galleons.[50]

    Plantation cultivation

    Further information: History of modern banana plantations in the Americas

    Plantation in the Philippines, 2010

    In the 15th and 16th centuries, Portuguese colonists started banana plantations in the Atlantic Islands, Brazil, and western Africa.[53] North Americans began consuming bananas on a small scale at very high prices shortly after the Civil War, though it was only in the 1880s that the food became more widespread.[54] As late as the Victorian Era, bananas were not widely known in Europe, although they were available.[53]

    The earliest modern plantations originated in Jamaica and the related Western Caribbean Zone, including most of Central America. Plantation cultivation involved the combination of modern transportation networks of steamships and railroads with the development of refrigeration that allowed more time between harvesting and ripening. North American shippers like Lorenzo Dow Baker and Andrew Preston, the founders of the Boston Fruit Company started this process in the 1870s, with the participation of railroad builders like Minor C. Keith. Development led to the multi-national giant corporations like Chiquita and Dole.[54] These companies were monopolisticvertically integrated (controlling growing, processing, shipping and marketing) and usually used political manipulation to build enclave economies (internally self-sufficient, virtually tax exempt, and export-oriented, contributing little to the host economy). Their political maneuvers, which gave rise to the term banana republic for states such as Honduras and Guatemala, included working with local elites and their rivalries to influence politics or playing the international interests of the United States, especially during the Cold War, to keep the political climate favorable to their interests.[55]

    Small-scale cultivation

    Further information: History of peasant banana production in the Americas

    Small-scale banana production, Liberia, 2013

    The vast majority of the world’s bananas are cultivated for family consumption or for sale on local markets. They are grown in large quantities in India, while many other Asian and African countries host numerous small-scale banana growers who sell at least some of their crop.[56] Peasants with smallholdings of 1 to 2 acres in the Caribbean produce bananas for the world market, often alongside other crops.[57] In many tropical countries, the main cultivars produce green (unripe) bananas used for cooking. Because bananas and plantains produce fruit year-round, they provide a valuable food source during the hunger season between harvests of other crops, and are thus important for global food security.[58]

    Modern cultivation

    See also: List of banana cultivars

    Bananas are propagated asexually from offshoots. The plant is allowed to produce two shoots at a time; a larger one for immediate fruiting and a smaller “sucker” or “follower” to produce fruit in 6–8 months.[8] As a non-seasonal crop, bananas are available fresh year-round.[59] They are grown in some 135 countries.[60]

    Cavendish

    Main article: Cavendish banana

    Grocery store photo of several bunches of bananas
    Cultivars in the Cavendish group dominate the world market.

    In global commerce in 2009, by far the most important cultivars belonged to the triploid Musa acuminata AAA group of Cavendish group bananas.[61] Disease is threatening the production of the Cavendish banana worldwide. It is unclear if any existing cultivar can replace Cavendish bananas, so various hybridisation and genetic engineering programs are attempting to create a disease-resistant, mass-market banana. One such strain that has emerged is the Taiwanese Cavendish or Formosana.[62][63][64]

    Ripening

    Export bananas are picked green, and ripened in special rooms upon arrival in the destination country. These rooms are air-tight and filled with ethylene gas to induce ripening. This mimics the normal production of this gas as a ripening hormone.[65][66] Ethylene stimulates the formation of amylase, an enzyme that breaks down starch into sugar, influencing the taste. Ethylene signals the production of pectinase, a different enzyme which breaks down the pectin between the cells of the banana, causing the banana to soften as it ripens.[65][66] The vivid yellow color many consumers in temperate climates associate with bananas is caused by ripening around 18 °C (64 °F), and does not occur in Cavendish bananas ripened in tropical temperatures (over 27 °C (81 °F)), which leaves them green.[67][68]

    Storage and transport

    Ralstonia solanacearum on an overripe banana

    Bananas are transported over long distances from the tropics to world markets.[69] To obtain maximum shelf life, harvest comes before the fruit is mature. The fruit requires careful handling, rapid transport to ports, cooling, and refrigerated shipping. The goal is to prevent the bananas from producing their natural ripening agent, ethylene. This technology allows storage and transport for 3–4 weeks at 13 °C (55 °F). On arrival, bananas are held at about 17 °C (63 °F) and treated with a low concentration of ethylene. After a few days, the fruit begins to ripen and is distributed for final sale. Ripe bananas can be held for a few days at home. If bananas are too green, they can be put in a brown paper bag with an apple or tomato overnight to speed up the ripening process.[70][71]

    Sustainability

    The excessive use of fertilizers contributes greatly to eutrophication in streams and lakes, harming aquatic life, while expanding banana production has led to deforestation. As soil nutrients are depleted, more forest is cleared for plantations. This causes soil erosion and increases the frequency of flooding.[72]

    Voluntary sustainability standards such as Rainforest Alliance and Fairtrade are being used to address some of these issues. Banana production certified in this way grew rapidly at the start of the 21st century to represent 36% of banana exports by 2016.[73] However, such standards are applied mainly in countries which focus on the export market, such as Colombia, Costa Rica, Ecuador, and Guatemala; worldwide they cover only 8–10% of production.[74]

    Breeding

    Mutation breeding can be used in this crop. Aneuploidy is a source of significant variation in allotriploid varieties. For one example, it can be a source of TR4 resistanceLab protocols have been devised to screen for such aberrations and for possible resulting disease resistances.[75] Wild Musa spp. provide useful resistance genetics, and are vital to breeding for TR4 resistance, as shown in introgressed resistance from wild relatives.[76] Bananas form a hybrid-polyploid complex; hybrids can be diploid, triploid, tetraploid, or pentaploid, i.e. they may have 2, 3, 4, or 5 sets of chromosomes. This makes them difficult to breed as hybrids are often sterile, in addition to the challenge of breeding seedless (parthenocarpic) varieties.[citation needed]

    The Honduran Foundation for Agricultural Research has bred a seedless banana that is resistant to both Panama disease and black Sigatoka disease. The team made use of the fact that “seedless” varieties do rarely produce seeds; they obtained around fifteen seeds from some 30,000 cultivated plants, pollinated by hand with pollen from wild Asian bananas.[77]

    Production and export

    BananasPlantainsTotal
     India34.5 34.5
     China11.8 11.8
     Uganda10.410.4
     Indonesia9.2 9.2
     Philippines5.93.19.0
     Nigeria8.08.0
     Ecuador6.10.96.9
     Brazil6.9 6.9
     Democratic Republic of the Congo0.84.95.7
     Cameroon0.94.75.5
     Colombia2.52.55.0
     Guatemala4.80.35.0
     Ghana0.14.84.9
     Angola4.6 4.6
     Tanzania3.50.64.1
     Rwanda2.20.93.1
     Costa Rica2.50.12.6
     Ivory Coast0.52.12.6
     Mexico2.62.6
     Dominican Republic1.41.22.5
     Vietnam2.52.5
     Peru2.42.4
    World135.144.2179.3
    Source: FAOSTAT of the United Nations[78] Note: Some countries distinguish between bananas and plantains, but four of the top six producers do not, thus necessitating comparisons using the total for bananas and plantains combined.

    As of 2018, bananas are exported in larger volume and to a larger value than any other fruit.[62] In 2022, world production of bananas and plantains combined was 179 million tonnes, led by India and China with a combined total of 26% of global production. Other major producers were Uganda, Indonesia, the Philippines, Nigeria and Ecuador.[78] As reported for 2013, total world exports were 20 million tonnes of bananas and 859,000 tonnes of plantains.[79] Ecuador and the Philippines were the leading exporters with 5.4 and 3.3 million tonnes, respectively, and the Dominican Republic was the leading exporter of plantains with 210,350 tonnes.[79]

    Pests

    Bananas are damaged by a variety of pests, especially nematodes and insects.[80]

    Nematodes

    Banana roots are subject to damage from multiple species of parasitic nematodesRadopholus similis causes nematode root rot, the most serious nematode disease of bananas in economic terms.[81] Root-knot is the result of infection by species of Meloidogyne,[82] while root-lesion is caused by species of Pratylenchus,[83] and spiral nematode root damage is the result of infection by Helicotylenchus species.[84]

    Radopholus similis inside banana root, causing nematode root rot

    Insects

    Among the main insect pests of banana cultivation are two beetles that cause substantial economic losses, the banana borer Cosmopolites sordidus and the banana stem weevil Odoiporus longicollis. Other significant pests include aphids and scarring beetles.[80]

    The banana borer is a destructive pest that tunnels inside the plant.[80]

    Diseases

    Main article: List of banana and plantain diseases

    Although in no danger of outright extinction, bananas of the Cavendish group, which dominate the global market, are under threat.[85] There is a need to enrich banana biodiversity by producing diverse new banana varieties, not just focusing on the Cavendish.[86] Its predecessor ‘Gros Michel‘, discovered in the 1820s, was similarly dominant but had to be replaced after widespread infections of Panama disease. Monocropping of Cavendish similarly leaves it susceptible to disease and so threatens both commercial cultivation and small-scale subsistence farming.[85][87] Within the data gathered from the genes of hundreds of bananas, the botanist Julie Sardos has found several wild banana ancestors currently unknown to scientists, whose genes could provide a means of defense against banana crop diseases.[88]

    Some commentators have remarked that those variants which could replace what much of the world considers a “typical banana” are so different that most people would not consider them the same fruit, and blame the decline of the banana on monogenetic cultivation driven by short-term commercial motives.[55] Overall, fungal diseases are disproportionately important to small island developing states.[89]

    Panama disease

    A banana tree cut horizontally to show the fungus development in the interior of the tree
    Panama disease Fusarium fungus climbing up through the banana stem

    Panama disease is caused by a Fusarium soil fungus, which enters the plants through the roots and travels with water into the trunk and leaves, producing gels and gums that cut off the flow of water and nutrients, causing the plant to wilt, and exposing the rest of the plant to lethal amounts of sunlight. Prior to 1960, almost all commercial banana production centered on the Gros Michel cultivar, which was highly susceptible.[90] Cavendish was chosen as the replacement for Gros Michel because, among resistant cultivars, it produces the highest quality fruit. It requires more care during shipping,[91] and its quality compared to Gros Michel is debated.[92]

    Fusarium wilt TR4

    Fusarium wilt TR4, a reinvigorated strain of Panama disease, was discovered in 1993. This virulent form of Fusarium wilt has destroyed Cavendish plantations in several southeast Asian countries and spread to Australia and India.[86] As the soil-based fungi can easily be carried on boots, clothing, or tools, the wilt spread to the Americas despite years of preventive efforts.[86] Without genetic diversity, Cavendish is highly susceptible to TR4, and the disease endangers its commercial production worldwide.[93] The only known defense to TR4 is genetic resistance.[86] This is conferred either by RGA2, a gene isolated from a TR4-resistant diploid banana, or by the nematode-derived Ced9.[94][95] This may be achieved by genetic modification.[94][95]

    Black sigatoka

    Leaf infected with black sigatoka

    Black sigatoka is a fungal leaf spot disease first observed in Fiji in 1963 or 1964. It is caused by the ascomycete Mycosphaerella fijiensis. The disease, also called black leaf streak, has spread to banana plantations throughout the tropics from infected banana leaves used as packing material. It affects all main cultivars of bananas and plantains (including the Cavendish cultivars[96]), impeding photosynthesis by blackening parts of the leaves, eventually killing the entire leaf. Starved for energy, fruit production falls by 50% or more, and the bananas that do grow ripen prematurely, making them unsuitable for export. The fungus has shown ever-increasing resistance to treatment; spraying with fungicides may be required as often as 50 times a year. Better strategies, with integrated pest management, are needed.[97][98]

    Banana bunchy top virus

    Infected Banana Plant
    Colony of banana aphids (Pentalonia nigronervosa), vector of banana bunchy top virus

    Banana bunchy top virus is a plant virus of the genus Babuvirus, family Nanonviridae affecting Musa spp. (including banana, abaca, plantain and ornamental bananas) and Ensete spp. in the family Musaceae.[99] Banana bunchy top disease symptoms include dark green streaks of variable length in leaf veins, midribs and petioles. Leaves become short and stunted as the disease progresses, becoming ‘bunched’ at the apex of the plant. Infected plants may produce no fruit or the fruit bunch may not emerge from the pseudostem.[100] The virus is transmitted by the banana aphid Pentalonia nigronervosa and is widespread in Southeast Asia, Asia, the Philippines, Taiwan, Oceania and parts of Africa. There is no cure, but it can be effectively controlled by the eradication of diseased plants and the use of virus-free planting material.[101] No resistant cultivars have been found, but varietal differences in susceptibility have been reported. The commercially important Cavendish subgroup is severely affected.[100]

    Banana bacterial wilt

    Banana bacterial wilt is a bacterial disease caused by Xanthomonas campestris pv. musacearum.[102] First identified on a close relative of bananas, Ensete ventricosum, in Ethiopia in the 1960s,[103] The disease was first seen in Uganda in 2001 affecting all banana cultivars. Since then it has been diagnosed in Central and East Africa, including the banana growing regions of Rwanda, the Democratic Republic of the Congo, Tanzania, Kenya, Burundi, and Uganda.[104]

    Conservation of genetic diversity

    The cold storage room for the banana collection at Bioversity International‘s Musa Germplasm Transit Centre

    Given the narrow range of genetic diversity present in bananas and the many threats via biotic (pests and diseases) and abiotic threats (such as drought) stress, conservation of the full spectrum of banana genetic resources is ongoing.[105] In 2024, the economist Pascal Liu of the FAO described the impact of global warming as an “enormous threat” to the world supply of bananas.[106]

    Banana germplasm is conserved in many national and regional gene banks, and at the world’s largest banana collection, the International Musa Germplasm Transit Centre, managed by Bioversity International and hosted at KU Leuven in Belgium.[107] Since Musa cultivars are mostly seedless, they are conserved by three main methods: in vivo (planted in field collections), in vitro (as plantlets in test tubes within a controlled environment), and by cryopreservation (meristems conserved in liquid nitrogen at −196 °C).[105]

    Genes from wild banana species are conserved as DNA and as cryopreserved pollen.[105] Seeds from wild species are sometimes conserved, although less commonly, as they are difficult to regenerate. In addition, bananas and their crop wild relatives are conserved in situ, in the wild natural habitats where they evolved and continue to do so. Diversity is also conserved in farmers’ fields where continuous cultivation, adaptation and improvement of cultivars is often carried out by small-scale farmers growing traditional local cultivars.[108]

    Nutrition

    Nutritional value per 100 g (3.5 oz)
    Energy371 kJ (89 kcal)
    Carbohydrates22.84 g
    Sugars12.23 g
    Dietary fiber2.6 g
    Fat0.33 g
    Protein1.09 g
    showVitamins and minerals
    Other constituentsQuantity
    Water74.91 g
    Link to USDA Database entry values are for edible portion
    Percentages estimated using US recommendations for adults,[109] except for potassium, which is estimated based on expert recommendation from the National Academies.[110]

    A raw banana (not including the peel) is 75% water, 23% carbohydrates, 1% protein, and contains negligible fat. A reference amount of 100 grams (3.5 oz) supplies 89 calories, 24% of the Daily Value of vitamin B6, and moderate amounts of vitamin Cmanganesepotassium, and dietary fiber, with no other micronutrients in significant content (table).

    Although bananas are commonly thought to contain exceptional potassium content,[111][112] their actual potassium content is not high per typical food serving, having only 12% of the Daily Value for potassium (table). The potassium-content ranking for bananas among fruits, vegetables, legumes, and many other foods is medium.[113][114]

    Uses

    Culinary

    Fruit

    See also: Cooking plantain and List of banana dishes

    Wikibooks Cookbook has a recipe/module on

    Bananas are a staple starch for many tropical populations. Depending upon cultivar and ripeness, the flesh can vary in taste from starchy to sweet, and texture from firm to mushy. Both the skin and inner part can be eaten raw or cooked. The primary component of the aroma of fresh bananas is isoamyl acetate (also known as banana oil), which, along with several other compounds such as butyl acetate and isobutyl acetate, is a significant contributor to banana flavor.[115]

    Plantains are eaten cooked, often as fritters.[116] Pisang goreng, bananas fried with batter, is a popular street food in Southeast Asia.[117] Bananas feature in Philippine cuisine, with desserts like maruya banana fritters.[118] Bananas can be made into fruit preserves.[119] Banana chips are a snack produced from sliced and fried bananas, such as in Kerala.[120] Dried bananas are ground to make banana flour.[121] In Africa, matoke bananas are cooked in a sauce with meat and vegetables such as peanuts or beans to make the breakfast dish katogo.[122] In Western countries, bananas are used to make desserts such as banana bread.[123]

    Flowers

    Wikibooks Cookbook has a recipe/module on

    Banana flowers (also called “banana hearts” or “banana blossoms”) are used as a vegetable[124] in South Asian and Southeast Asian cuisine. The flavor resembles that of artichoke. As with artichokes, both the fleshy part of the bracts and the heart are edible.[125]

    • Banana flowers and leaves on sale in Thailand
    • Kilawin na pusô ng saging, a Filipino dish of banana flowers

    Leaf

    Main article: Banana leaf

    Banana leaves are large, flexible, and waterproof. While generally too tough to actually be eaten, they are often used as ecologically friendly disposable food containers or as “plates” in South Asia and several Southeast Asian countries.[126] In Indonesian cuisine, banana leaf is employed in cooking methods like pepes and botok; banana leaf packages containing food ingredients and spices are cooked in steam or in boiled water, or are grilled on charcoal. Certain types of tamales are wrapped in banana leaves instead of corn husks.[127]

    When used so for steaming or grilling, the banana leaves protect the food ingredients from burning and add a subtle sweet flavor.[1] In South India, it is customary to serve traditional food on a banana leaf.[128] In Tamil Nadu (India), dried banana leaves are used as to pack food and to make cups to hold liquid food items.[129]

    Trunk

    Main article: Banana pith

    The tender core of the banana plant’s trunk is also used in South Asian and Southeast Asian cuisine.[130] Examples include the Burmese dish mohinga, and the Filipino dishes inubaran and kadyos, manok, kag ubad.[131][132]

    • Kaeng yuak, a northern Thai curry of the core of the banana plant

    Paper and textiles

    Further information: Manila hemp and Banana paper

    Banana fiber harvested from the pseudostems and leaves has been used for textiles in Asia since at least the 13th century. Both fruit-bearing and fibrous banana species have been used.[133] In the Japanese system Kijōka-bashōfu, leaves and shoots are cut from the plant periodically to ensure softness. Harvested shoots are first boiled in lye to prepare fibers for yarn-making. These banana shoots produce fibers of varying degrees of softness, yielding yarns and textiles with differing qualities for specific uses. For example, the outermost fibers of the shoots are the coarsest, and are suitable for tablecloths, while the softest innermost fibers are desirable for kimono and kamishimo. This traditional Japanese cloth-making process requires many steps, all performed by hand.[134] Banana paper can be made either from the bark of the banana plant, mainly for artistic purposes, or from the fibers of the stem and non-usable fruits. The paper may be hand-made or industrially processed.[135]

    • Packing Manila hemp (Musa textilis) into bales, Java
    • Weaving looms processing Manila hemp fabric
    • A modern Manila hemp bag

    Other uses

    The large leaves of bananas are locally used as umbrellas.[1] Banana peel may have capability to extract heavy metal contamination from river water, similar to other purification materials.[136][137] Waste bananas can be used to feed livestock.[138] As with all living things, potassium-containing bananas emit radioactivity at low levels occurring naturally from the potassium-40 (K-40) isotope.[139] The banana equivalent dose of radiation was developed in 1995 as a simple teaching-tool to educate the public about the natural, small amount of K-40 radiation occurring in everyone and in common foods.[140][111]

    Potential allergic reaction

    Individuals with a latex allergy may experience a reaction to handling or eating bananas.[141][142]

    Cultural roles

    Bananas used in puja in the Hindu festival of Chhath in Northern India

    Arts

    The Edo period poet Matsuo Bashō is named after the Japanese word 芭蕉 (Bashō) for the Japanese banana. The Bashō planted in his garden by a grateful student became a source of inspiration to his poetry, as well as a symbol of his life and home.[143]

    The song “Yes! We Have No Bananas” was written by Frank Silver and Irving Cohn and originally released in 1923; for many decades, it was the best-selling sheet music in history. Since then the song has been rerecorded several times and has been particularly popular during banana shortages.[144][145]

    A person slipping on a banana peel has been a staple of physical comedy for generations. An American comedy recording from 1910 features a popular character of the time, “Uncle Josh”, claiming to describe his own such incident.[146]

    The banana’s suggestively phallic shape has been exploited in artworks from Giorgio de Chirico’s 1913 painting The Uncertainty of the Poet onwards. In 2019, an exhibition of Natalia LL‘s video and set of photographs showing a woman “sucking on a banana” at the National Museum in Warsaw was taken down and the museum’s director reprimanded.[147] The cover artwork for the 1967 debut album of The Velvet Underground features a banana made by Andy Warhol. On the original vinyl LP version, the design allowed the listener to “peel” this banana to find a pink, peeled banana on the inside.[148] In 1989, the feminist Guerilla Girls made a screenprint with two bananas, intentionally reminiscent of Warhol’s, arranged to form a “0” to answer the question in the artwork, “How many works by women artists were in the Andy Warhol and Tremaine auctions at Sotheby’s?”.[149]

    Italian artist Maurizio Cattelan created a 2019 concept art piece titled Comedian[150] involving taping a banana to a wall using silver duct tape. The piece was exhibited briefly at the Art Basel in Miami before being removed from the exhibition and eaten without permission in another artistic stunt titled Hungry Artist by New York artist David Datuna.[151]

    Religion and folklore

    Nang Tani, the female ghost of Thai folklore that haunts banana plants

    In India, bananas serve a prominent part in many festivals and occasions of Hindus. In South Indian weddings, particularly Tamil weddings, banana trees are tied in pairs to form an arch as a blessing to the couple for a long-lasting, useful life.[152][153]

    In Thailand, it is believed that a certain type of banana plant may be inhabited by a spirit, Nang Tani, a type of ghost related to trees and similar plants that manifests itself as a young woman.[154] People often tie a length of colored satin cloth around the pseudostem of the banana plants.[155]

    In Malay folklore, the ghost known as Pontianak is associated with banana plants (pokok pisang), and its spirit is said to reside in them during the day.[156]

    Racial signifier

    See also: List of ethnic slurs § Banana, and Racism in sport

    In European, British, and Australian sport, throwing a banana at a member of an opposing team has long been used as a form of racial abuse.[157][158] The act, which was commonplace in England in the 1980s, is meant to taunt players of Black African ancestry by equating them to apes or monkeys.[

  • Apple

    An apple is a round, edible fruit produced by an apple tree (Malus spp.). Fruit trees of the orchard or domestic apple (Malus domestica), the most widely grown in the genus, are cultivated worldwide. The tree originated in Central Asia, where its wild ancestor, Malus sieversii, is still found. Apples have been grown for thousands of years in Eurasia before they were introduced to North America by European colonists. Apples have cultural significance in many mythologies (including Norse and Greek) and religions (such as Christianity in Europe).

    Apples grown from seed tend to be very different from those of their parents, and the resultant fruit frequently lacks desired characteristics. For commercial purposes, including botanical evaluation, apple cultivars are propagated by clonal grafting onto rootstocks. Apple trees grown without rootstocks tend to be larger and much slower to fruit after planting. Rootstocks are used to control the speed of growth and the size of the resulting tree, allowing for easier harvesting.

    There are more than 7,500 cultivars of apples. Different cultivars are bred for various tastes and uses, including cooking, eating raw, and cider or apple juice production. Trees and fruit are prone to fungal, bacterial, and pest problems, which can be controlled by a number of organic and non-organic means. In 2010, the fruit’s genome was sequenced as part of research on disease control and selective breeding in apple production.

    Etymology

    The word apple, whose Old English ancestor is æppel, is descended from the Proto-Germanic noun *aplaz, descended in turn from Proto-Indo-European *h₂ébōl.[3] As late as the 17th century, the word also functioned as a generic term for all fruit, including nuts. This can be compared to the 14th-century Middle English expression appel of paradis, meaning a banana.[4]

    Description

    The apple is a deciduous tree, generally standing 2 to 4.5 metres (6 to 15 feet) tall in cultivation and up to 15 m (49 ft) in the wild, though more typically 2 to 10 m (6.5 to 33 ft).[5][1] When cultivated, the size, shape and branch density are determined by rootstock selection and trimming method.[5] Apple trees may naturally have a rounded to erect crown with a dense canopy of leaves.[6] The bark of the trunk is dark gray or gray-brown, but young branches are reddish or dark-brown with a smooth texture.[1][7] Young twigs are covered in fine downy hairs; they become hairless when older.[7]

    The buds are egg-shaped and dark red or purple in color; they range in size from 3 to 5 millimeters, but are usually less than 4 mm. The bud scales have very hairy edges. When emerging from the buds, the leaves are convolute, meaning that their edges overlap each other.[1] Leaves can be simple ovals (elliptic), medium or wide in width, somewhat egg-shaped with the wider portion toward their base (ovate), or even with sides that are more parallel to each other instead of curved (oblong) with a narrow pointed end.[7][1] The edges have broadly-angled teeth, but do not have lobes. The top surface of the leaves are glabrescent, almost hairless, while the undersides are densely covered in fine hairs.[1] The leaves are attached alternately by short leaf stems 1-to-3.5 cm (12-to-1+12 in) long.[6][1]

    Blossoms are produced in spring simultaneously with the budding of the leaves and are produced on spurs and some long shoots.[5] When the flower buds first begin to open the petals are rose-pink and fade to white or light pink when fully open with each flower 3-to-4-centimeter (1-to-1+12-inch) in diameter.[1] The five-petaled flowers are group in an inflorescence consisting of a cyme with 3–7 flowers.[8] The central flower of the inflorescence is called the “king bloom”; it opens first and can develop a larger fruit.[6] Open apple blossoms are damaged by even brief exposures to temperatures −2 °C (28 °F) or less, although the overwintering wood and buds are hardy down to −40 °C (−40 °F).[8]

    • Apple blossoms
    • Botanical illustration

    Fruit

    The fruit is a pome that matures in late summer or autumn.[1] The true fruits or carpels are the harder interior chambers inside the apple’s core. There are usually five carpels inside an apple, but there may be as few as three. Each of the chambers contains one or two seeds.[9] The edible flesh is formed from the receptacle at the base of the flower.[10]

    • How apple fruit derives from flower structures

    The seeds are egg- to pear-shaped and may be colored from light brown or tan to a very dark brown, often with red shades or even purplish-black. They may have a blunt or sharp point.[11] The five sepals remain attached and stand out from the surface of the apple.[1]

    The size of the fruit varies widely between cultivars, but generally has a diameter between 2.5 and 12 cm (1 and 5 in).[7] The shape is quite variable and may be nearly round, elongated, conical, or short and wide.[12]

    The groundcolor of ripe apples is yellow, green, yellow-green or whitish yellow. The overcolor of ripe apples can be orange-red, pink-red, red, purple-red or brown-red. The overcolor amount can be 0–100%.[13] The skin may be wholly or partly russeted, making it rough and brown. The skin is covered in a protective layer of epicuticular wax.[14] The skin may also be marked with scattered dots.[1] The flesh is generally pale yellowish-white, though it can be pink, yellow or green.[13]

    Apples can have any amount of overcolor, a darker tint over a pale groundcolor.

    • 0% overcolor
    • 100% overcolor

    Chemistry

    Important volatile compounds in apples that contribute to their scent and flavour include acetaldehydeethyl acetate1-butanalethanol, 2-methylbutanal, 3-methylbutanalethyl propionate, ethyl 2-methylpropionate, ethyl butyrate, ethyl 2-methyl butyrate, hexanal1-butanol3-methylbutyl acetate, 2-methylbutyl acetate, 1-propyl butyrate, ethyl pentanoateamyl acetate2-methyl-1-butanol, trans-2-hexenal, ethyl hexanoatehexanol.[15][16]

    Taxonomy

    The apple as a species has more than 100 alternative scientific names, or synonyms.[17] In modern times, Malus pumila and Malus domestica are the two main names in use. M. pumila is the older name, but M. domestica has become much more commonly used starting in the 21st century, especially in the western world. Two proposals were made to make M. domestica a conserved name: the earlier proposal was voted down by the Committee for Vascular Plants of the IAPT in 2014, but in April 2017 the Committee decided, with a narrow majority, that the newly popular name should be conserved.[18] The General Committee of the IAPT decided in June 2017 to approve this change, officially conserving M. domestica.[19] Nevertheless, some works published after 2017 still use M. pumila as the correct name, under an alternate taxonomy.[2]

    When first classified by Linnaeus in 1753, the pears, apples, and quinces were combined into one genus that he named Pyrus and he named the apple as Pyrus malus. This was widely accepted, however the botanist Philip Miller published an alternate classification in The Gardeners Dictionary with the apple species separated from Pyrus in 1754. He did not clearly indicate that by Malus pumila he meant the domesticated apple. Nonetheless, it was used as such by many botanists. When Moritz Balthasar Borkhausen published his scientific description of the apple in 1803 it may have been a new combination of P. malus var. domestica, but this was not directly referenced by Borkhausen.[17] The earliest use of var. domestica for the apple was by Georg Adolf Suckow in 1786.[2]

    Genome

    Further information: Apple genome

    Apples are diploid, with two sets of chromosomes per cell (though triploid cultivars, with three sets, are not uncommon), have 17 chromosomes and an estimated genome size of approximately 650 Mb. Several whole genome sequences have been completed and made available. The first one in 2010 was based on the diploid cultivar ‘Golden Delicious‘.[20] However, this first whole genome sequence contained several errors,[21] in part owing to the high degree of heterozygosity in diploid apples which, in combination with an ancient genome duplication, complicated the assembly. Recently, double- and trihaploid individuals have been sequenced, yielding whole genome sequences of higher quality.[22][23]

    The first whole genome assembly was estimated to contain around 57,000 genes,[20] though the more recent genome sequences support estimates between 42,000 and 44,700 protein-coding genes.[22][23] The availability of whole genome sequences has provided evidence that the wild ancestor of the cultivated apple most likely is Malus sieversii. Re-sequencing of multiple accessions has supported this, while also suggesting extensive introgression from Malus sylvestris following domestication.[24]

    Cultivation

    History

    Map of the origins of the cultivated apple. The wild origin is in Kazakhstan; hybridisations and repeated domestications followed, modifying many attributes of the fruit.[24]
    color photograph of a hand holding a red apple
    Wild Malus sieversii apple in Kazakhstan

    Central Asia is generally considered the center of origin for apples due to the genetic variability in specimens there.[25] The wild ancestor of Malus domestica was Malus sieversii, found growing wild in the mountains of Central Asia in southern KazakhstanKyrgyzstanTajikistan, and northwestern China.[5][26] Cultivation of the species, most likely beginning on the forested flanks of the Tian Shan mountains, progressed over a long period of time and permitted secondary introgression of genes from other species into the open-pollinated seeds. Significant exchange with Malus sylvestris, the crabapple, resulted in populations of apples being more related to crabapples than to the more morphologically similar progenitor Malus sieversii. In strains without recent admixture the contribution of the latter predominates.[27][28][29]

    The apple is thought to have been domesticated 4,000–10,000 years ago in the Tian Shan mountains, and then to have travelled along the Silk Road to Europe, with hybridization and introgression of wild crabapples from Siberia (M. baccata), the Caucasus (M. orientalis), and Europe (M. sylvestris). Only the M. sieversii trees growing on the western side of the Tian Shan mountains contributed genetically to the domesticated apple, not the isolated population on the eastern side.[24]

    Chinese soft apples, such as M. asiatica and M. prunifolia, have been cultivated as dessert apples for more than 2,000 years in China. These are thought to be hybrids between M. baccata and M. sieversii in Kazakhstan.[24]

    Among the traits selected for by human growers are size, fruit acidity, color, firmness, and soluble sugar. Unusually for domesticated fruits, the wild M. sieversii origin is only slightly smaller than the modern domesticated apple.[24]

    At the Sammardenchia-Cueis site near Udine in Northeastern Italy, seeds from some form of apples have been found in material carbon dated to between 6570 and 5684 BCE.[30] Genetic analysis has not yet been successfully used to determine whether such ancient apples were wild Malus sylvestris or Malus domesticus containing Malus sieversii ancestry. It is hard to distinguish in the archeological record between foraged wild apples and apple plantations.[31]

    There is indirect evidence of apple cultivation in the third millennium BCE in the Middle East.[31] There is direct evidence, apple cores, dated to the 10th century BCE from a Judean site between the Sinai and Negev. [32] There was substantial apple production in European classical antiquity, and grafting was certainly known then.[31] Grafting is an essential part of modern domesticated apple production, to be able to propagate the best cultivars; it is unclear when apple tree grafting was invented.[31]

    “Wild Apples”
    by Henry David Thoreau
    Read by Kevin S for LibriVox

    Duration: 1 hour, 1 minute and 36 seconds.1:01:36

    Audio 01:01:35 (full text)


    Problems playing this file? See media help.

    The Roman writer Pliny the Elder describes a method of storage for apples from his time in the 1st century. He says they should be placed in a room with good air circulation from a north facing window on a bed of straw, chaff, or mats with windfalls kept separately.[33] Though methods like this will extend the availabity of reasonably fresh apples, without refrigeration their lifespan is limited. Even sturdy winter apple varieties will only keep well until December in cool climates.[34] For longer storage medieval Europeans strung up cored and peeled apples to dry, either whole or sliced into rings.[35]

    Of the many Old World plants that the Spanish introduced to Chiloé Archipelago in the 16th century, apple trees became particularly well adapted.[36] Apples were introduced to North America by colonists in the 17th century,[5] and the first named apple cultivar was introduced in Boston by Reverend William Blaxton in 1640.[37] The only apples native to North America are crab apples.[38]

    Apple cultivars brought as seed from Europe were spread along Native American trade routes, as well as being cultivated on colonial farms. An 1845 United States apples nursery catalogue sold 350 of the “best” cultivars, showing the proliferation of new North American cultivars by the early 19th century.[38] In the 20th century, irrigation projects in Eastern Washington began and allowed the development of the multibillion-dollar fruit industry, of which the apple is the leading product.[5]

    Until the 20th century, farmers stored apples in frostproof cellars during the winter for their own use or for sale. Improved transportation of fresh apples by train and road replaced the necessity for storage.[39][40] Controlled atmosphere facilities are used to keep apples fresh year-round. Controlled atmosphere facilities use high humidity, low oxygen, and controlled carbon dioxide levels to maintain fruit freshness. They were first researched at Cambridge University in the 1920s and first used in the United States in the 1950s.[41]

    Breeding

    See also: Fruit tree propagation and Malling series

    An apple tree in Germany

    Many apples grow readily from seeds. However, apples must be propagated asexually to obtain cuttings with the characteristics of the parent. This is because seedling apples are “extreme heterozygotes“. Rather than resembling their parents, seedlings are all different from each other and from their parents.[42] Triploid cultivars have an additional reproductive barrier in that three sets of chromosomes cannot be divided evenly during meiosis, yielding unequal segregation of the chromosomes (aneuploids). Even in the case when a triploid plant can produce a seed (apples are an example), it occurs infrequently, and seedlings rarely survive.[43]

    Because apples are not true breeders when planted as seeds, propagation usually involves grafting of cuttings. The rootstock used for the bottom of the graft can be selected to produce trees of a large variety of sizes, as well as changing the winter hardiness, insect and disease resistance, and soil preference of the resulting tree. Dwarf rootstocks can be used to produce very small trees (less than 3.0 m or 10 ft high at maturity), which bear fruit many years earlier in their life cycle than full size trees, and are easier to harvest.[44]

    Dwarf rootstocks for apple trees can be traced as far back as 300 BCE, to the area of Persia and Asia MinorAlexander the Great sent samples of dwarf apple trees to Aristotle‘s Lyceum. Dwarf rootstocks became common by the 15th century and later went through several cycles of popularity and decline throughout the world.[45] The majority of the rootstocks used to control size in apples were developed in England in the early 1900s. The East Malling Research Station conducted extensive research into rootstocks, and their rootstocks are given an “M” prefix to designate their origin. Rootstocks marked with an “MM” prefix are Malling-series cultivars later crossed with trees of ‘Northern Spy‘ in Merton, England.[46]

    Most new apple cultivars originate as seedlings, which either arise by chance or are bred by deliberately crossing cultivars with promising characteristics.[47] The words “seedling”, “pippin”, and “kernel” in the name of an apple cultivar suggest that it originated as a seedling. Apples can also form bud sports (mutations on a single branch). Some bud sports turn out to be improved strains of the parent cultivar. Some differ sufficiently from the parent tree to be considered new cultivars.[48]

    Apples have been acclimatized in Ecuador at very high altitudes, where they can often, with the needed factors, provide crops twice per year because of constant temperate conditions year-round.[49]

    Pollination

    See also: Fruit tree pollination

    • An apple blossom from an old Ayrshire cultivar
    • An orchard mason bee on an apple bloom

    Apples are self-incompatible; they must cross-pollinate to develop fruit. During the flowering each season, apple growers often utilize pollinators to carry pollen. Honey bees are most commonly used. Orchard mason bees are also used as supplemental pollinators in commercial orchards. Bumblebee queens are sometimes present in orchards, but not usually in sufficient number to be significant pollinators.[48][50]

    Cultivars are sometimes classified by the day of peak bloom in the average 30-day blossom period, with pollinizers selected from cultivars within a 6-day overlap period. There are four to seven pollination groups in apples, depending on climate:

    • Group A – Early flowering, 1 to 3 May in England (‘Gravenstein‘, ‘Red Astrachan’)
    • Group B – 4 to 7 May (‘Idared‘, ‘McIntosh‘)
    • Group C – Mid-season flowering, 8 to 11 May (‘Granny Smith‘, ‘Cox’s Orange Pippin‘)
    • Group D – Mid/late season flowering, 12 to 15 May (‘Golden Delicious‘, ‘Calville blanc d’hiver’)
    • Group E – Late flowering, 16 to 18 May (‘Braeburn‘, ‘Reinette d’Orléans’)
    • Group F – 19 to 23 May (‘Suntan’)
    • Group H – 24 to 28 May (‘Court-Pendu Gris’ – also called Court-Pendu plat)

    One cultivar can be pollinated by a compatible cultivar from the same group or close (A with A, or A with B, but not A with C or D).[51]

    Maturation and harvest

    See also: Fruit picking and Fruit tree pruning

    Cultivars vary in their yield and the ultimate size of the tree, even when grown on the same rootstock. Some cultivars, if left unpruned, grow very large—letting them bear more fruit, but making harvesting more difficult. Depending on tree density (number of trees planted per unit surface area), mature trees typically bear 40–200 kg (90–440 lb) of apples each year, though productivity can be close to zero in poor years. Apples are harvested using three-point ladders that are designed to fit amongst the branches. Trees grafted on dwarfing rootstocks bear about 10–80 kg (20–180 lb) of fruit per year.[48]

    Some farms with apple orchards open them to the public so consumers can pick their own apples.[52]

    Crops ripen at different times of the year according to the cultivar. Cultivar that yield their crop in the summer include ‘Sweet Bough‘ and ‘Duchess’; fall producers include ‘Blenheim’; winter producers include ‘King’, ‘Swayzie‘, and ‘Tolman Sweet’.[38]

    Storage

    Rome apples on sale at a farmer’s market in Newark, Delaware, United States (2011)

    Commercially, apples can be stored for months in controlled atmosphere chambers. Apples are commonly stored in chambers with lowered concentrations of oxygen to reduce respiration and slow softening and other changes if the fruit is already fully ripe. The gas ethylene is used by plants as a hormone which promotes ripening, decreasing the time an apple can be stored. For storage longer than about six months the apples are picked earlier, before full ripeness, when ethylene production by the fruit is low. However, in many varieties this increases their sensitivity to carbon dioxide, which also must be controlled.[53]

    For home storage, most culitvars of apple can be stored for three weeks in a pantry and four to six weeks from the date of purchase in a refrigerator that maintains 4 to 0 °C (39 to 32 °F).[54][55] Some varieties of apples (e.g. ‘Granny Smith‘ and ‘Fuji‘) have more than three times the storage life of others.[56]

    Non-organic apples may be sprayed with a substance 1-methylcyclopropene blocking the apples’ ethylene receptors, temporarily preventing them from ripening.[57]

    Pests and diseases

    Further information: List of apple diseases

    Codling moth larva tunnelling inside an apple

    Apple trees are susceptible to fungal and bacterial diseases, and to damage by insect pests. Many commercial orchards pursue a program of chemical sprays to maintain high fruit quality, tree health, and high yields. These prohibit the use of synthetic pesticides, though some older pesticides are allowed. Organic methods include, for instance, introducing its natural predator to reduce the population of a particular pest.

    A wide range of pests and diseases can affect the plant. Three of the more common diseases or pests are mildew, aphids, and apple scab.

    • Mildew is characterized by light grey powdery patches appearing on the leaves, shoots and flowers, normally in spring. The flowers turn a creamy yellow color and do not develop correctly. This can be treated similarly to Botrytis—eliminating the conditions that caused the disease and burning the infected plants are among recommended actions.[58]
    • Aphids are small insects with sucking mouthparts. Five species of aphids commonly attack apples: apple grain aphid, rosy apple aphid, apple aphid, spirea aphid, and the woolly apple aphid. The aphid species can be identified by color, time of year, and by differences in the cornicles (small paired projections from their rear).[59] Aphids feed on foliage using needle-like mouth parts to suck out plant juices. When present in high numbers, certain species reduce tree growth and vigor.[60]
    • Apple scab: Apple scab causes leaves to develop olive-brown spots with a velvety texture that later turn brown and become cork-like in texture. The disease also affects the fruit, which also develops similar brown spots with velvety or cork-like textures. Apple scab is spread through fungus growing in old apple leaves on the ground and spreads during warm spring weather to infect the new year’s growth.[61]

    Among the most serious disease problems is a bacterial disease called fireblight, and three fungal diseases: Gymnosporangium rust, black spot,[62] and bitter rot.[63] Codling moths, and the apple maggots of fruit flies, cause serious damage to apple fruits, making them unsaleable. Young apple trees are also prone to mammal pests like mice and deer, which feed on the soft bark of the trees, especially in winter.[61] The larvae of the apple clearwing moth (red-belted clearwing) burrow through the bark and into the phloem of apple trees, potentially causing significant damage.[64]

    Cultivars

    Main article: List of apple cultivars

    From left to right: the ‘Golden Delicious‘, ‘SweeTango‘, ‘Granny Smith‘, and ‘Gala‘ apples.

    There are more than 7,500 known cultivars (cultivated varieties) of apples.[65] Cultivars vary in their yield and the ultimate size of the tree, even when grown on the same rootstock.[66] Different cultivars are available for temperate and subtropical climates. The UK’s National Fruit Collection, which is the responsibility of the Department of Environment, Food, and Rural Affairs, includes a collection of over 2,000 cultivars of apple tree in Kent.[67] The University of Reading, which is responsible for developing the UK national collection database, provides access to search the national collection. The University of Reading’s work is part of the European Cooperative Programme for Plant Genetic Resources of which there are 38 countries participating in the Malus/Pyrus work group.[68]

    The UK’s national fruit collection database contains much information on the characteristics and origin of many apples, including alternative names for what is essentially the same “genetic” apple cultivar. Most of these cultivars are bred for eating fresh (dessert apples), though some are cultivated specifically for cooking (cooking apples) or producing ciderCider apples are typically too tart and astringent to eat fresh, but they give the beverage a rich flavor that dessert apples cannot.[69]

    In Europe, apple breeding programs are conducted at places such as Julius Kühn-Institut, the German federal research center for cultivated plants.[70]

    In the United States there are many apple breeding programs associated with universities. For instance, in the East, Cornell University has had a program operating since 1880 in Geneva, New York, while in the West, Washington State University started a program to support their home state’s apple industry in 1994.[71] Released by the University of Minnesota in 1991, the ‘Honeycrisp‘ has become famous for its crispness and juiciness, thereby commanding high market prices.[71] Unusually for a popular cultivar, the ‘Honeycrisp’ is not directly related to another popular apple cultivar but instead to two unsuccessful cultivars.[72] However, it is also difficult to grow and to store, prompting the industry to seek hybrids that not only appeal to consumers are also less costly for farmers to cultivate and last longer in storage.[73] By the 2020s, about half of the new apple varieties entering the market in the United States and Canada are ‘Honeycrisp’ progeny.[74] Such hybrids include the ‘SweeTango‘ (a cross between the ‘Honeycrisp’ and the ‘Zestar‘) introduced by the University of Minnesota in 2008 and the ‘Cosmic Crisp‘ (the ‘Honeycrisp’ and the ‘Enterprise‘) released by Washington State University in 2017.[73]

    Less common apple cultivars from an orchard in Italy

    Commercially popular apple cultivars are soft but crisp. Other desirable qualities in modern commercial apple breeding are a colorful skin, absence of russeting, ease of shipping, lengthy storage ability, high yields, disease resistance, common apple shape, and developed flavor.[66] Modern apples are generally sweeter than older cultivars, as popular tastes in apples have varied over time.[75] Most North Americans and Europeans favor crunchy, sweet, and subacid apples.[76] Nevertheless, tart apples maintain a strong minority following.[77] In the United States today, the most popular apple varieties are the ‘Ambrosia‘, ‘Honeycrisp’, and ‘Jazz‘, according Nielsen data,[73] while in Canada, the ‘Honeyscrisp’, ‘Ambrosia’, and ‘Gala’ take the top spots.[75] Together, these relatively newer varieties have overtaken once dominant cultivars like the ‘McIntosh‘ and the ‘Red Delicious‘ in the North American market.[75][76] Extremely sweet apples with barely any acid flavor are popular in Asia,[77] especially the Indian subcontinent.[69]

    Old cultivars are often oddly shaped, russeted, and grow in a variety of textures and colors. Some find them to have better flavor than modern cultivars, but they may have other problems that make them commercially unviable—low yield, disease susceptibility, poor tolerance for storage or transport, or just being the “wrong” size.[78] A few old cultivars are still produced on a large scale, but many have been preserved by home gardeners and farmers that sell directly to local markets. Many unusual and locally important cultivars with their own unique taste and appearance exist; apple conservation campaigns have sprung up around the world to preserve such local cultivars from extinction. In the United Kingdom, old cultivars such as ‘Cox’s Orange Pippin‘ and ‘Egremont Russet‘ are still commercially important even though by modern standards they are low yielding and susceptible to disease.[5]

    Production

    Main article: List of countries by apple production

    Apple production
    2023, millions of tonnes
     China49.6
     United States5.2
     Turkey4.6
     Poland3.9
     India2.9
     Iran2.2
    World97.3
    Source: FAOSTAT of the United Nations[79]

    World production of apples in 2023 was 97 million tonnes, with China producing 51% of the total (table).[79] Secondary producers were the United States, Turkey, and Poland.[79]

    Toxicity

    Amygdalin

    Apple seeds contain small amounts of amygdalin, a sugar and cyanide compound known as a cyanogenic glycoside. Ingesting small amounts of apple seeds causes no ill effects, but consumption of extremely large doses can cause adverse reactions. It may take several hours before the poison takes effect, as cyanogenic glycosides must be hydrolyzed before the cyanide ion is released.[80] The U.S. National Library of Medicine‘s Hazardous Substances Data Bank records no cases of amygdalin poisoning from consuming apple seeds.[81]

    Allergy

    One form of apple allergy, often found in northern Europe, is called birch-apple syndrome and is found in people who are also allergic to birch pollen.[82] Allergic reactions are triggered by a protein in apples that is similar to birch pollen, and people affected by this protein can also develop allergies to other fruits, nuts, and vegetables. Reactions, which entail oral allergy syndrome (OAS), generally involve itching and inflammation of the mouth and throat,[82] but in rare cases can also include life-threatening anaphylaxis.[83] This reaction only occurs when raw fruit is consumed—the allergen is neutralized in the cooking process. The variety of apple, maturity and storage conditions can change the amount of allergen present in individual fruits. Long storage times can increase the amount of proteins that cause birch-apple syndrome.[82]

    In other areas, such as the Mediterranean, some individuals have adverse reactions to apples because of their similarity to peaches.[82] This form of apple allergy also includes OAS, but often has more severe symptoms, such as vomiting, abdominal pain and urticaria, and can be life-threatening. Individuals with this form of allergy can also develop reactions to other fruits and nuts. Cooking does not break down the protein causing this particular reaction, so affected individuals cannot eat raw or cooked apples. Freshly harvested, over-ripe fruits tend to have the highest levels of the protein that causes this reaction.[82]

    Breeding efforts have yet to produce a hypoallergenic fruit suitable for either of the two forms of apple allergy.[82]

    Uses

    See also: Cooking apple and Cider apple

    Nutrition

    Nutritional value per 100 g (3.5 oz)
    Energy218 kJ (52 kcal)
    Carbohydrates13.81 g
    Sugars10.39
    Dietary fiber2.4 g
    Fat0.17 g
    Protein0.26 g
    showVitamins and minerals
    Other constituentsQuantity
    Water85.56 g
    Link to Full Nutrient Report of USDA Database entry
    Percentages estimated using US recommendations for adults,[84] except for potassium, which is estimated based on expert recommendation from the National Academies.[85]

    A raw apple is 86% water and 14% carbohydrates, with negligible content of fat and protein (table). A reference serving of a raw apple with skin weighing 100 g (3.5 oz) provides 52 calories and a moderate content of dietary fiber (table). Otherwise, there is low content of micronutrients, with the Daily Values of all falling below 10% (table).

    Culinary

    Further information: List of apple dishes

    Machine for paring, coring, and slicing apples, from Henry B. Scammell’s 1897 handbook Cyclopedia of Valuable Receipts

    Apples varieties can be grouped as cooking appleseating apples, and cider apples, the last so astringent as to be “almost inedible”.[86] Apples are consumed as juice, raw in salads, baked in pies, cooked into sauces and apple butter, or baked.[87] They are sometimes used as an ingredient in savory foods, such as sausage and stuffing.[88]

    Several techniques are used to preserve apples and apple products. Traditional methods include drying and making apple butter.[86] Juice and cider are produced commercially; cider is a significant industry in regions such as the West of England and Normandy.[86]

    toffee apple (UK) or caramel apple (US) is a confection made by coating an apple in hot toffee or caramel candy respectively and allowing it to cool.[89][8] Apples and honey are a ritual food pairing eaten during the Jewish New Year of Rosh Hashanah.[90]

    Apples are an important ingredient in many desserts, such as piescrumbles, and cakes. When cooked, some apple cultivars easily form a puree known as apple sauce, which can be cooked down to form a preserve, apple butter. They are often baked or stewed, and are cooked in some meat dishes.[86]

    Apples are milled or pressed to produce apple juice, which may be drunk unfiltered (called apple cider in North America), or filtered. Filtered juice is often concentrated and frozen, then reconstituted later and consumed. Apple juice can be fermented to make cider (called hard cider in North America), ciderkin, and vinegar.[8] Through distillation, various alcoholic beverages can be produced, such as applejackCalvados, and apple brandy.[8][91]

    Organic production

    Organic apples are commonly produced in the United States.[92] Due to infestations by key insects and diseases, organic production is difficult in Europe.[93] The use of pesticides containing chemicals, such as sulfur, copper, microorganisms, viruses, clay powders, or plant extracts (pyrethrumneem) has been approved by the EU Organic Standing Committee to improve organic yield and quality.[93] A light coating of kaolin, which forms a physical barrier to some pests, also may help prevent apple sun scalding.[48]

    Non-browning apples

    Apple skins and seeds contain polyphenols.[94] These are oxidised by the enzyme polyphenol oxidase, which causes browning in sliced or bruised apples, by catalyzing the oxidation of phenolic compounds to o-quinones, a browning factor.[95] Browning reduces apple taste, color, and food value. Arctic apples, a non-browning group of apples introduced to the United States market in 2019, have been genetically modified to silence the expression of polyphenol oxidase, thereby delaying a browning effect and improving apple eating quality.[96][97] The US Food and Drug Administration in 2015, and Canadian Food Inspection Agency in 2017, determined that Arctic apples are as safe and nutritious as conventional apples.[98][99]

    Other products

    Apple seed oil is obtained by pressing apple seeds for manufacturing cosmetics.[100]

    In culture

    Main article: Apple (symbolism)

    Germanic paganism

    Illustration of girl in a red dress, holding 3 candles in one hand and a basket of apples in the other
    “Brita as Iduna” (1901) by Carl Larsson

    In Norse mythology, the goddess Iðunn is portrayed in the Prose Edda (written in the 13th century by Snorri Sturluson) as providing apples to the gods that give them eternal youthfulness. The English scholar H. R. Ellis Davidson links apples to religious practices in Germanic paganism, from which Norse paganism developed. She points out that buckets of apples were found in the Oseberg ship burial site in Norway, and that fruits and nuts have been found in the early graves of the Germanic peoples in England and elsewhere in Europe. The fruits and nuts may have had a symbolic meaning, and nuts are still a recognized symbol of fertility in southwest England.[101]

    Davidson notes a connection between apples and the Vanir, a tribe of gods associated with fertility in Norse mythology, citing an instance of eleven “golden apples” being given to woo the beautiful Gerðr by Skírnir, who was acting as messenger for the major Vanir god Freyr in stanzas 19 and 20 of Skírnismál. Davidson also notes a further connection between fertility and apples in Norse mythology in chapter 2 of the Völsunga saga: when the major goddess Frigg sends King Rerir an apple after he prays to Odin for a child, Frigg’s messenger (in the guise of a crow) drops the apple in his lap as he sits atop a mound.[101] Rerir’s wife’s consumption of the apple results in a six-year pregnancy and the birth (by Caesarean section) of their son—the hero Völsung.[102]

    Further, Davidson points out the “strange” phrase “Apples of Hel” used in an 11th-century poem by the skald Thorbiorn Brúnarson. She states this may imply that the apple was thought of by Brúnarson as the food of the dead. Further, Davidson notes that the potentially Germanic goddess Nehalennia is sometimes depicted with apples and that parallels exist in early Irish stories. Davidson asserts that while cultivation of the apple in Northern Europe extends back to at least the time of the Roman Empire and came to Europe from the Near East, the native varieties of apple trees growing in Northern Europe are small and bitter. Davidson concludes that in the figure of Iðunn “we must have a dim reflection of an old symbol: that of the guardian goddess of the life-giving fruit of the other world.”[101]

    Greek mythology

    Heracles with the apple of Hesperides

    Apples appear in many religious traditions, including Greek and Roman mythology where it has an ambiguous symbolism of discord, fertility, or courtship.[103] In Greek mythology, the Greek hero Heracles, as a part of his Twelve Labours, was required to travel to the Garden of the Hesperides and pick the golden apples off the Tree of Life growing at its center.[104]

    The Greek goddess of discord, Eris, became disgruntled after she was excluded from the wedding of Peleus and Thetis.[105] In retaliation, she tossed a golden apple inscribed Καλλίστη (Kallistē, “For the most beautiful one”), into the wedding party. Three goddesses claimed the apple: HeraAthena, and AphroditeParis of Troy was appointed to select the recipient. After being bribed by both Hera and Athena, Aphrodite tempted him with the most beautiful woman in the world, Helen of Sparta. He awarded the apple to Aphrodite, thus indirectly causing the Trojan War.[106][107]

    The apple was thus considered, in ancient Greece, sacred to Aphrodite. To throw an apple at someone was to symbolically declare one’s love; and similarly, to catch it was to symbolically show one’s acceptance of that love. An epigram claiming authorship by Plato states:[108]

    I throw the apple at you, and if you are willing to love me, take it and share your girlhood with me; but if your thoughts are what I pray they are not, even then take it, and consider how short-lived is beauty.

    — Plato, Epigram VII

    Atalanta, also of Greek mythology, raced all her suitors in an attempt to avoid marriage. She outran all but Hippomenes (also known as Melanion, a name possibly derived from melon, the Greek word for both “apple” and fruit in general),[104] who defeated her by cunning, not speed. Hippomenes knew that he could not win in a fair race, so he used three golden apples (gifts of Aphrodite, the goddess of love) to distract Atalanta. It took all three apples and all of his speed, but Hippomenes was finally successful, winning the race and Atalanta’s hand.[109][110]

    Celtic mythology

    In Celtic mythology, the otherworld has many names, including Emain Ablach, “Emain of the Apple-trees”. A version of this is Avalon in Arthurian legend, or in Welsh Ynys Afallon, “Island of Apples”.[111]

    China

    Píngānguǒ (“Peace apples”) on sale in Beijing for Christmas Eve (2017)

    In China, apples symbolise peace, since the sounds of the first element (“píng”) in the words “apple” (苹果, Píngguǒ) and “peace” (平安, Píng’ān) are homophonous in Mandarin and Cantonese.[3][112] When these two words are combined, the word Píngānguǒ (平安果, “Peace apples”) is formed. This association developed further as the name for Christmas Eve in Mandarin is Píngānyè (平安夜, “Peaceful/Quiet Evening”), which made the gifting of apples at this season to friends and associates popular, as a way to wish them peace and safety.[112]

    Christian art

    Adam and Eve by Albrecht Dürer (1507), showcasing the apple as a symbol of sin

    Though the forbidden fruit of Eden in the Book of Genesis is not identified, popular Christian tradition has held that it was an apple that Eve coaxed Adam to share with her.[113] The origin of the popular identification with a fruit unknown in the Middle East in biblical times is found in wordplay with the Latin words mālum (an apple) and mălum (an evil), each of which is normally written malum.[114] The tree of the forbidden fruit is called “the tree of the knowledge of good and evil” in Genesis 2:17,[115] and the Latin for “good and evil” is bonum et malum.[116]

    Renaissance painters may also have been influenced by the story of the golden apples in the Garden of Hesperides. As a result, in the story of Adam and Eve, the apple became a symbol for knowledge, immortality, temptation, the fall of man into sin, and sin itself. The larynx in the human throat has been called the “Adam’s apple” because of a notion that it was caused by the forbidden fruit remaining in the throat of Adam. The apple as symbol of sexual seduction has been used to imply human sexuality, possibly in an ironic vein.[113]

    Proverb

    The proverb, “An apple a day keeps the doctor away“, addressing the supposed health benefits of the fruit, has been traced to 19th-century Wales, where the original phrase was “Eat an apple on going to bed, and you’ll keep the doctor from earning his bread”.[117] In the 19th century and early 20th, the phrase evolved to “an apple a day, no doctor to pay” and “an apple a day sends the doctor away”; the phrasing now commonly used was first recorded in 1922.