Banana

Banana is the common name for an edible fruit produced by several kinds of large herbaceous flowering plants of the genus Musa. The fruit is variable in size, colour and firmness, but is usually elongated and curved, with soft flesh rich in starch covered with a rind which may be yellow, purple or red when ripe. The fruits grow in clusters hanging from the top of the plant. Almost all modern edible parthenocarpic (seedless) bananas come from two wild species – Musa acuminata and Musa balbisiana. The scientific names of most cultivated bananas are Musa acuminata, Musa balbisiana, and Musa × paradisiaca for the hybrid Musa acuminata × M. balbisiana, depending on their genomic constitution. The old scientific name Musa sapientum is no longer used.

Musa species are native to tropical South and Southeast Asia, and are likely to have been first domesticated in Papua New Guinea. They are grown in at least 107 countries, primarily for their fruit, and to a lesser extent to make fibre, banana wine and as ornamental plants.

Worldwide, there is no sharp distinction between "bananas" and "plantains". Especially in the Americas and Europe, "banana" usually refers to soft, sweet, dessert bananas, particularly those of the Cavendish group, which are the main exports from banana-growing countries. By contrast, Musa cultivars with firmer, starchier fruit are called "plantains". In other regions, such as Southeast Asia, many more kinds of banana are grown and eaten, so that the simple two-fold distinction is not useful and is not made in local languages.

The term "banana" is also used as the common name for the plants which produce the fruit. This can extend to other members of the genus Musa like the scarlet banana (Musa coccinea), pink banana (Musa velutina) and the Fe'i bananas. It can also refer to members of the genus Ensete, like the snow banana (Ensete glaucum) and the economically important false banana (Ensete ventricosum). Both genera are classified under the banana family, Musaceae.

Description

The banana plant is the largest herbaceous flowering plant. All the above-ground parts of a banana plant grow from a structure usually called a " corm". Plants are normally tall and fairly sturdy, and are often mistaken for trees, but what appears to be a trunk is actually a "false stem" or pseudostem. 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. 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. Leaves are spirally arranged and may grow 2.7 metres (8.9 ft) long and 60 cm (2.0 ft) wide. They are easily torn by the wind, resulting in the familiar frond look.

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. Each pseudostem normally produces a single inflorescence, also known as the "banana heart". (More are sometimes produced; an exceptional plant in the Philippines produced five.) After fruiting, the pseudostem dies, but offshoots will normally have developed from the base, so that the plant as a whole is perennial. In the plantation system of cultivation, only one of the offshoots will be allowed to develop in order to maintain spacing. The inflorescence contains many bracts (sometimes incorrectly called petals) 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.

The banana fruits develop from the banana heart, in a large hanging cluster, made up of tiers (called "hands"), with up to 20 fruit to a tier. The hanging cluster is known as a bunch, comprising 3–20 tiers, or commercially as a "banana stem", and can weigh from 30–50 kilograms (66–110 lb). Individual banana fruits (commonly known as a banana or "finger") average 125 grams (0.28 lb), of which approximately 75% is water and 25% dry matter.

The fruit has been described as a "leathery berry". There is a protective outer layer (a peel or skin) with numerous long, thin strings (the phloem bundles), which run lengthwise between the skin and the edible inner portion. The inner part of the common yellow dessert variety splits easily lengthwise into three sections that correspond to the inner portions of the three carpels. In cultivated varieties, the seeds are diminished nearly to non-existence; their remnants are tiny black specks in the interior of the fruit.

Bananas are naturally slightly radioactive, more so than most other fruits, because of their potassium content and the small amounts of the isotope potassium-40 found in naturally occurring potassium. Proponents of nuclear power sometimes refer to the banana equivalent dose of radiation to support their arguments.

Taxonomy

The genus Musa is 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 sources assert that Musa is named for Antonius Musa, physician to the Emperor Augustus. Others say that Linnaeus, who named the genus in 1750, simply adapted an Arabic word for banana, mauz. The word banana is generally said to be derived from the Wolof word banaana. Some 70 species of Musa were recognized by the World Checklist of Selected Plant Families as of January 2013; several produce edible fruit, while others are cultivated as ornamentals.

Banana classification has long been a problematic issue for taxonomists. Linnaeus originally classified bananas into two species based only on their uses as food: Musa sapientum for dessert bananas and Musa paradisiaca for plantains. Subsequently further species names were added. However, this approach proved inadequate to address the sheer number of cultivars existing in the primary centre of diversity of the genus, Southeast Asia. Many of these cultivars were given names which proved to be synonyms.

In a series of papers published in 1947 onwards, Ernest Cheesman showed that Linnaeus' Musa sapientum and Musa paradisiaca were actually cultivars and descendants of two wild seed-producing species, Musa acuminata and Musa balbisiana, both first described by Luigi Aloysius Colla. He recommended the abolition of Linnaeus' species in favour 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 that are the combination of the two. 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 Linnaeus' Musa sapientum and Musa paradisiaca. Despite this, the original names are still recognized by some authorities today, leading to confusion.

The currently accepted scientific names for bananas are Musa acuminata Colla and Musa balbisiana Colla for the ancestral species, and Musa × paradisiaca L. for the hybrid M. acuminata × M. balbisiana.

Synonyms of M. × paradisica include:

• A large number of subspecific and varietial names of M. × paradisiaca, including M. p. subsp. sapientum (L.) Kuntze
• Musa × dacca Horan.
• Musa × sapidisiaca K.C.Jacob, nom. superfl.
• Musa × sapientum L., and a large number of its varietal names, including M. × sapientum var. paradisiaca (L.) Baker, nom. illeg.

Generally, modern classifications of banana cultivars follow Simmonds and Shepherd's system. Cultivars are placed in groups based on the number of chromosomes they have and which species they are derived from. Thus the Latundan banana is placed in the AAB Group, showing that it is a triploid derived from both M. acuminata (A) and M. balbisiana (B). For a list of the cultivars classified under this system see List of banana cultivars.

In 2012 a team of scientists announced they had achieved a draft sequence of the genome of Musa acuminata.

Bananas and plantains

In regions such as North America and Europe, Musa fruits offered for sale can be divided into "bananas" and "plantains", based on their intended use as food. Thus the banana producer and distributor Chiquita produces publicity material for the American market which says that "a plantain is not a banana". The stated differences are that plantains are more starchy and less sweet; they are eaten cooked rather than raw; they have thicker skin, which may be green, yellow or black; and they can be used at any stage of ripeness. Linnaeus made the same distinction between plantains and bananas when first naming two "species" of Musa. Members of the " Plantain subgroup" of banana cultivars, most important as food in West Africa and Latin America, correspond to the Chiquita description, having long pointed fruit. They are described by Ploetz et al. as "true" plantains, distinct from other cooking bananas. The cooking bananas of East Africa belong to a different group, the East African Highland bananas, so would not qualify as "true" plantains on this definition.

An alternative approach divides bananas into dessert bananas and cooking bananas, with plantains being one of the subgroups of cooking bananas. Triploid cultivars derived solely from M. acuminata are examples of "dessert bananas", whereas triploid cultivars derived from the hybrid between M. acuminata and M. balbinosa (in particular the Plantain subgroup of the AAB Group) are "plantains". Small farmers in Colombia grow a much wider range of cultivars than large commercial plantations. A study of these cultivars showed that they could be placed into at least three groups based on their characteristics: dessert bananas, non-plantain cooking bananas, and plantains, although there were overlaps between dessert and cooking bananas.

In Southeast Asia – the centre of diversity for bananas, both wild and cultivated – the distinction between "bananas" and "plantains" does not work, according to Valmayor et al. 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. Southeast Asian languages do not make the distinction between "bananas" and "plantains" that is made in English (and Spanish). Thus both Cavendish cultivars, the classic yellow dessert bananas, and Saba cultivars, used mainly for cooking, are called pisang in Malaysia and Indonesia, kluai in Thailand and chuoi in Vietnam. Fe'i bananas, grown and eaten in the islands of the Pacific, are derived from entirely different wild species than traditional bananas and plantains. Most Fe'i bananas are cooked, but Karat bananas, which are short and squat with bright red skins, very different from the usual yellow dessert bananas, are eaten raw.

In summary, in commerce in Europe and the Americas (although not in small-scale cultivation), it is possible to distinguish between "bananas", which are eaten raw, and "plantains", which are cooked. In other regions of the world, particularly India, Southeast Asia and the islands of the Pacific, there are many more kinds of banana and the two-fold distinction is not useful and not made in local languages. Plantains are one of many kinds of cooking bananas, which are not always distinct from dessert bananas.

Historical cultivation

Early cultivation

Southeast Asian farmers first domesticated bananas. Recent archaeological and palaeoenvironmental evidence at Kuk Swamp in the Western Highlands Province of Papua New Guinea suggests that banana cultivation there goes back to at least 5000 BCE, and possibly to 8000 BCE. It is likely that other species were later and independently domesticated elsewhere in southeast Asia. Southeast Asia is the region of primary diversity of the banana. Areas of secondary diversity are found in Africa, indicating a long history of banana cultivation in the region.

Phytolith discoveries in Cameroon dating to the first millennium BCE triggered an as yet unresolved debate about the date of first cultivation in Africa. There is linguistic evidence that bananas were known in Madagascar around that time. The earliest prior evidence indicates that cultivation dates to no earlier than late 6th century CE. It is likely, however, that bananas were brought at least to Madagascar if not to the East African coast during the phase of Malagasy colonization of the island from South East Asia c. 400 CE.

The banana may have been present in isolated locations of the Middle East on the eve of Islam. There is some textual evidence that Muhammad was familiar with bananas. 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 appears in texts from Palestine and Egypt. From there it diffused into north Africa and Muslim Iberia. During the medieval ages, bananas from Granada were considered among the best in the Arab world. In 650, Islamic conquerors brought the banana to Palestine. Today, banana consumption increases significantly in Islamic countries during Ramadan, the month of daylight fasting.

Bananas were introduced to the Americas by Portuguese sailors who brought the fruits from West Africa in the 16th century. The word banana is of West African origin, from the Wolof language, and passed into English via Spanish or Portuguese.

Many wild banana species as well as cultivars exist in extraordinary diversity in New Guinea, Malaysia, Indonesia, China, and the Philippines.

There are fuzzy bananas whose skins are bubblegum pink; green-and-white striped bananas with pulp the colour of orange sherbet; bananas that, when cooked, taste like strawberries. The Double Mahoi plant can produce two bunches at once. The Chinese name of the aromatic Go San Heong banana means 'You can smell it from the next mountain.' The fingers on one banana plant grow fused; another produces bunches of a thousand fingers, each only an inch long.

—Mike Peed, The New Yorker

Plantation cultivation in the Caribbean, Central and South America

In the 15th and 16th centuries, Portuguese colonists started banana plantations in the Atlantic Islands, Brazil, and western Africa. 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 it became more widespread. As late as the Victorian Era, bananas were not widely known in Europe, although they were available. Jules Verne introduces bananas to his readers with detailed descriptions in Around the World in Eighty Days (1872).

The earliest modern plantations originated in Jamaica and the related Western Caribbean Zone, including most of Central America. It involved the combination of modern transportation networks of steamships and railroads with the development of refrigeration that allowed bananas to have more time between harvesting and ripening. North America shippers like Lorenzo Dow Baker and Andrew Preston, the founders of the Boston Fruit Company started this process in the 1870s, but railroad builders like Minor C Keith also participated, eventually culminating in the multi-national giant corporations like today's Chiquita Brands International and Dole. These companies were monopolistic, vertically integrated (meaning they controlled growing, processing, shipping and marketing) and usually used political manipulation to build enclave economies (economies that were internally self-sufficient, virtually tax exempt, and export oriented that contribute very little to the host economy). Their political maneuvers, which gave rise to the term Banana republic for states like 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.

Peasant cultivation for export in the Caribbean

The vast majority of the world's bananas today are cultivated for family consumption or for sale on local markets. India is the world leader in this sort of production, but many other Asian and African countries where climate and soil conditions allow cultivation also host large populations of banana growers who sell at least some of their crop.

There are peasant sector banana growers who produce for the world market in the Caribbean, however. The Windward Islands are notable for the growing, largely of Cavendish bananas, for an international market, generally in Europe but also in North America. In the Caribbean, and especially in Dominica where this sort of cultivation is widespread, holdings are in the 1–2 acre range. In many cases the farmer earns additional money from other crops, from engaging in labor outside the farm, and from a share of the earnings of relatives living overseas. This style of cultivation often was popular in the islands as bananas required little labor input and brought welcome extra income. Banana crops are vulnerable to destruction by high winds, such as tropical storms or cyclones.

After the signing of the NAFTA agreements in the 1990s, however, the tide turned against peasant producers. Their costs of production were relatively high and the ending of favorable tariff and other supports, especially in the European Economic Community, made it difficult for peasant producers to compete with the bananas grown on large plantations by the well capitalized firms like Chiquita and Dole. Not only did the large companies have access to cheap labor in the areas they worked, but they were better able to afford modern agronomic advances such as fertilization. The "dollar banana" produced by these concerns made the profit margins for peasant bananas unsustainable.

Caribbean countries have sought to redress this problem by providing government supported agronomic services and helping to organize producers' cooperatives. They have also been supporters of the Fair Trade movement which seeks to balance the inequities in the world trade in commodities.

East Africa

Most farms supply local consumption. Cooking bananas represent a major food source and a major income source for smallhold farmers. In east Africa, highland bananas are of greatest importance as a staple food crop. In countries such as Uganda, Burundi, and Rwanda per capita consumption has been estimated at 45 kilograms (99 lb) per year, the highest in the world.

Modern cultivation

All widely cultivated bananas today descend from the two wild bananas Musa acuminata and Musa balbisiana. While the original wild bananas contained large seeds, diploid or polyploid cultivars (some being hybrids) with tiny seeds are preferred for human raw fruit consumption. These 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. The life of a banana plantation is 25 years or longer, during which time the individual stools or planting sites may move slightly from their original positions as lateral rhizome formation dictates.

Cultivated bananas are parthenocarpic, i.e. the flesh of the fruit swells and ripens without its seeds being fertilized and developing. Lacking viable seeds, propagation typically involves farmers removing and transplanting part of the underground stem (called a corm). Usually this is done by carefully removing a sucker (a vertical shoot that develops from the base of the banana pseudostem) with some roots intact. However, small sympodial corms, representing not yet elongated suckers, are easier to transplant and can be left out of the ground for up to two weeks; they require minimal care and can be shipped in bulk.

It is not necessary to include the corm or root structure to propagate bananas; severed suckers without root material can be propagated in damp sand, although this takes somewhat longer.

In some countries, commercial propagation occurs by means of tissue culture. This method is preferred since it ensures disease-free planting material. When using vegetative parts such as suckers for propagation, there is a risk of transmitting diseases (especially the devastating Panama disease).

As a non-seasonal crop, bananas are available fresh year-round.

Cavendish

In global commerce, by far the most important cultivars belong to the triploid AAA group of Musa acuminata, commonly referred to as Cavendish group bananas. They account for the majority of banana exports, despite only coming into existence in 1836. The cultivars Dwarf Cavendish and Grand Nain (Chiquita Banana) gained popularity in the 1950s after the previous mass-produced cultivar, Gros Michel (also an AAA group cultivar), became commercially unviable due to Panama disease, caused by the fungus Fusarium oxysporum which attacks the roots of the banana plant.

Ease of transport and shelf life rather than superior taste make the Dwarf Cavendish the main export banana.

Even though it is no longer viable for large scale cultivation, Gros Michel is not extinct and is still grown in areas where Panama disease is not found. Likewise, Dwarf Cavendish and Grand Nain are in no danger of extinction, but they may leave supermarket shelves if disease makes it impossible to supply the global market. 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.

Ripening

Export bananas are picked green, and ripen in special rooms upon arrival in the destination country. These rooms are air-tight and filled with ethylene gas to induce ripening. The vivid yellow colour normally associated with supermarket bananas is in fact a side effect of the artificial ripening process. Flavor and texture are also affected by ripening temperature. Bananas are refrigerated to between 13.5 and 15 °C (56 and 59 °F) during transport. At lower temperatures, ripening permanently stalls, and turns the bananas gray as cell walls break down. The skin of ripe bananas quickly blackens in the 4 °C (39 °F) environment of a domestic refrigerator, although the fruit inside remains unaffected.

"Tree-ripened" Cavendish bananas have a greenish-yellow appearance which changes to a brownish-yellow as they ripen further. Although both flavor and texture of tree-ripened bananas is generally regarded as superior to any type of green-picked fruit, this reduces shelf life to only 7–10 days.

Bananas can be ordered by the retailer "ungassed", and may show up at the supermarket fully green. " Guineo Verde", or green bananas that have not been gassed will never fully ripen before becoming rotten. Instead of fresh eating, these bananas are best suited to cooking, as seen in Mexican culinary dishes.

A 2008 study reported that ripe bananas fluoresce when exposed to ultraviolet light. This property is attributed to the degradation of chlorophyll leading to the accumulation of a fluorescent product in the skin of the fruit. The chlorophyll breakdown product is stabilized by a propionate ester group. Banana-plant leaves also fluoresce in the same way. Green bananas do not fluoresce. The study suggested that this allows animals which can see light in the ultraviolet spectrum ( tetrachromats and pentachromats) to more easily detect ripened bananas.

Storage and transport

Bananas must be transported over long distances from the tropics to world markets. 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. Unripe bananas can not be held in home refrigerators because they suffer from the cold. 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.

Carbon dioxide (which bananas produce) and ethylene absorbents extend fruit life even at high temperatures. This effect can be exploited by packing banana in a polyethylene bag and including an ethylene absorbent, e.g., potassium permanganate, on an inert carrier. The bag is then sealed with a band or string. This treatment has been shown to more than double lifespans up to 3–4 weeks without the need for refrigeration.

Production and export

Production and export of bananas and plantains by country (2011)

Country	Millions of tonnes	Percentage of world total
Table 1: Production
India	29.7	20%
Uganda	11.1	8%
China	10.7	7%
Philippines	9.2	6%
Ecuador	8.0	6%
Brazil	7.3	5%
Indonesia	6.1	4%
Colombia	5.1	4%
Cameroon	4.8	3%
Tanzania	3.9	3%
All other countries	49.6	34%
Total world	145.4	100%
Table 2: Exports
Ecuador	5.2	29%
Costa Rica	1.8	10%
Colombia	1.8	10%
Philippines	1.6	9%
Guatemala	1.5	8%
All other countries	6.0	34%
Total world	17.9	100%

Statistics on the production and export of bananas and plantains are available from the Food and Agriculture Organization. Some countries produce statistics which distinguish between bananas and plantains, but three of the top four producers (India, China and the Philippines) do not, so comparisons can only be made using the total for bananas and plantains combined. The 2011 statistics (see Table 1) show that India led the world in banana production, producing around 20% of the worldwide crop of 145 million metric tonnes. Uganda was the next largest producer with around 8% of the worldwide crop. Its national data does distinguish between bananas and plantains, and shows that the latter made up over 95% of production. Ten countries produced around two thirds of the total world production.

The statistics for the export of bananas and plantains show a rather different picture (see Table 2). Total world exports at around 18 million metric tonnes amounted to only 12% of total world production; two thirds of the exports were generated by only five countries. The top three producing countries do not appear in this table, and two countries, Costa Rica and Guatemala, do not appear in the table of top producers. Only the Philippines has a consistent position in both tables. Exports were dominated by Ecuador, with 29% of the world total. Statistics for Ecuador distinguish between bananas and plantains; 93% of its exports were classified as bananas.

Bananas and plantains constitute a major staple food crop for millions of people in developing countries. In most tropical countries, green (unripe) bananas used for cooking represent the main cultivars. Bananas are cooked in ways that are similar to potatoes. Both can be fried, boiled, baked, or chipped and have similar taste and texture when served. One banana provides about the same calories as one potato.

Most producers are small-scale farmers either for home consumption or local markets. Because bananas and plantains produce fruit year-round, they provide an extremely valuable food source during the hunger season (when the food from one annual/semi-annual harvest has been consumed, and the next is still to come). Bananas and plantains are therefore critical to global food security.

Bananas have been an important source of disagreement in the Doha Round of trade talks. A study for ICTSD showed that the new deal on EU banana import tariffs will be a boon to Latin American exporters but would trigger a drop in exports of the fruit from African, Caribbean and Pacific ( ACP) countries.

Bananas are among the most widely consumed foods in the world. Most banana farmers receive a low price for their produce as grocery companies pay discounted prices for buying in enormous quantity. Price competition among grocers has reduced their margins, leading to lower prices for growers. Chiquita, Del Monte, Dole, and Fyffes grow their own bananas in Ecuador, Colombia, Costa Rica, Guatemala, and Honduras. Banana plantations are capital intensive and demand significant expertise. The majority of independent growers are large and wealthy landowners in these countries. Producers have attempted to raise prices via marketing them as " fair trade" or Rainforest Alliance-certified in some countries.

The banana has an extensive trade history starting with firms such as Fyffes and the United Fruit Company (now Chiquita) at the end of the 19th century. For much of the 20th century, bananas and coffee dominated the export economies of Central America. In the 1930s, bananas and coffee made up as much as 75% of the region's exports. As late as 1960, the two crops accounted for 67% of the exports from the region. Though the two were grown in similar regions, they tended not to be distributed together. The United Fruit Company based its business almost entirely on the banana trade, because the coffee trade proved too difficult to control. The term " banana republic" has been applied to most countries in Central America, but from a strict economic perspective only Costa Rica, Honduras, and Panama had economies dominated by the banana trade.

The European Union has traditionally imported many of their bananas from former European Caribbean colonies, paying guaranteed prices above global market rates (see Lomé Convention) As of 2005, these arrangements were in the process of being withdrawn under pressure from other major trading powers, principally the United States. The withdrawal of these indirect subsidies to Caribbean producers is expected to favour the banana producers of Central America, in which American companies have an economic interest.

The United States produces few bananas. A mere 14,000 tonnes (14,000 long tons; 15,000 short tons) were grown in Hawaii in 2001. Bananas were once grown in Florida and southern California.

Pests, diseases, and natural disasters

While in no danger of outright extinction, the most common edible banana cultivar Cavendish (extremely popular in Europe and the Americas) could become unviable for large-scale cultivation in the next 10–20 years. Its predecessor ' Gros Michel', discovered in the 1820s, suffered this fate. Like almost all bananas, Cavendish lacks genetic diversity, which makes it vulnerable to diseases, threatening both commercial cultivation and small-scale subsistence farming. Some commentators 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.

Panama disease

Panama disease is caused by a fusarium soil fungus (Race 1), 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 "Gros Michel", which was highly susceptible. Cavendish was chosen as the replacement for Gros Michel because, among resistant cultivars, it produces the highest quality fruit. However, more care is required for shipping the Cavendish, and its quality compared to Gros Michel is debated.

According to current sources, a deadly form of Panama disease is infecting Cavendish. All plants are genetically identical, which prevents evolution of disease resistance. Researchers are examining hundreds of wild varieties for resistance.

Tropical Race 4

TR4 is a reinvigorated strain of Panama disease first discovered in 1993. This virulent form of fusarium wilt has wiped out Cavendish in several southeast Asian countries. It has yet to reach the Americas; however, soil fungi can easily be carried on boots, clothing, or tools. This is how Tropical Race 4 travels and is its most likely route into Latin America. Cavendish is highly susceptible to TR4, and over time, Cavendish is almost certain to disappear from commercial production by this disease. Unfortunately, the only known defense to TR4 is genetic resistance.

Black Sigatoka

Black sigatoka is a fungal leaf spot disease first observed in Fiji in 1963 or 1964. Black Sigatoka (also known as black leaf streak) has spread to banana plantations throughout the tropics from infected banana leaves that were used as packing material. It affects all main cultivars of bananas and plantains, 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, with the current expense for treating 1 hectare (2.5 acres) exceeding $1,000 per year. In addition to the expense, there is the question of how long intensive spraying can be environmentally justified. Several resistant cultivars of banana have been developed, but none has yet received commercial acceptance due to taste and texture issues.

In East Africa

With the arrival of Black sigatoka, banana production in eastern Africa fell by over 40%. For example, during the 1970s, Uganda produced 15 to 20 tonnes (15 to 20 long tons; 17 to 22 short tons) of bananas per hectare. Today, production has fallen to only 6 tonnes (5.9 long tons; 6.6 short tons) per hectare.

The situation has started to improve as new disease-resistant cultivars have been developed by the International Institute of Tropical Agriculture and the National Agricultural Research Organisation of Uganda (NARO), such as FHIA-17 (known in Uganda as the Kabana 3). These new cultivars taste different from the Cabana banana, which has slowed their acceptance by local farmers. However, by adding mulch and manure to the soil around the base of the plant, these new cultivars have substantially increased yields in the areas where they have been tried.

The International Institute of Tropical Agriculture and NARO, funded by the Rockefeller Foundation and CGIAR have started trials for genetically modified bananas that are resistant to both Black sigatoka and banana weevils. It is developing cultivars specifically for smallholder and subsistence farmers.

Banana Bunchy Top Virus (BBTV)

This virus jumps from plant to plant using aphids. It stunts leaves, resulting in a "bunched" appearance. Generally, an infected plant does not produce fruit, although mild strains exist which allow some production. These mild strains are often mistaken for malnourishment, or a disease other than BBTV. There is no cure; however, its effect can be minimized by planting only tissue-cultured plants (in vitro propagation), controlling aphids, and immediately removing and destroying infected plants.

Culture

Food and cooking

Fruit

Banana, raw, edible parts

Nutritional value per 100 g (3.5 oz)
Energy	371 kJ (89 kcal)
Carbohydrates	22.84 g
- Sugars	12.23 g
- Dietary fibre	2.6 g
Fat	0.33 g
Protein	1.09 g
Vitamin A equiv.	3 μg (0%)
Thiamine (vit. B1)	0.031 mg (3%)
Riboflavin (vit. B2)	0.073 mg (6%)
Niacin (vit. B3)	0.665 mg (4%)
Pantothenic acid (B5)	0.334 mg (7%)
Vitamin B6	0.4 mg (31%)
Folate (vit. B9)	20 μg (5%)
Choline	9.8 mg (2%)
Vitamin C	8.7 mg (10%)
Calcium	5 mg (1%)
Iron	0.26 mg (2%)
Magnesium	27 mg (8%)
Manganese	0.3 mg (14%)
Phosphorus	22 mg (3%)
Potassium	358 mg (8%)
Zinc	0.15 mg (2%)
Percentages are relative to US recommendations for adults. Source: USDA Nutrient Database

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 banana's flavor is due, amongst other chemicals, to isoamyl acetate which is one of the main constituents of banana oil.

During the ripening process, bananas produce a plant hormone called ethylene, which indirectly affects the flavor. Among other things, ethylene stimulates the formation of amylase, an enzyme that breaks down starch into sugar, influencing the taste of bananas. The greener, less ripe bananas contain higher levels of starch and, consequently, have a "starchier" taste. On the other hand, yellow bananas taste sweeter due to higher sugar concentrations. Furthermore, ethylene signals the production of pectinase, an enzyme which breaks down the pectin between the cells of the banana, causing the banana to soften as it ripens.

Bananas are eaten deep fried, baked in their skin in a split bamboo, or steamed in glutinous rice wrapped in a banana leaf. Bananas can be made into jam. Banana pancakes are popular amongst backpackers and other travelers in South Asia and Southeast Asia. This has elicited the expression Banana Pancake Trail for those places in Asia that cater to this group of travelers. Banana chips are a snack produced from sliced dehydrated or fried banana or plantain, which have a dark brown colour and an intense banana taste. Dried bananas are also ground to make banana flour. Extracting juice is difficult, because when a banana is compressed, it simply turns to pulp. Bananas feature prominently in Philippine cuisine, being part of traditional dishes and desserts like maruya, turrón, and halo-halo. Most of these dishes use the Saba or Cardaba banana cultivar. Pisang goreng, bananas fried with batter similar to the Filipino maruya, is a popular dessert in Malaysia, Singapore, and Indonesia. A similar dish is known in the United States as banana fritters.

Plantains are used in various stews and curries or cooked, baked or mashed in much the same way as potatoes.

Seeded bananas ( Musa balbisiana), one of the forerunners of the common domesticated banana, are sold in markets in Indonesia.

Flower

Banana hearts are used as a vegetable in South Asian and Southeast Asian cuisine, either raw or steamed with dips or cooked in soups, curries and fried foods. The flavor resembles that of artichoke. As with artichokes, both the fleshy part of the bracts and the heart are edible.

Leaves

Banana leaves are large, flexible, and waterproof. They are often used as ecologically friendly disposable food containers or as "plates" in South Asia and several Southeast Asian countries. Especially in the South Indian states of Tamil Nadu, Karnataka, Andhra Pradesh and Kerala in every occasion the food must be served in a banana leaf and as a part of the food a banana is served. Steamed with dishes they impart a subtle sweet flavor. They often serve as a wrapping for grilling food. The leaves contain the juices, protect food from burning and add a subtle flavor. In Tamil Nadu (India) leaves are fully dried and used as packing material for food stuffs and also making cups to hold liquid foods. In Central American countries, banana leaves are often used as wrappers for tamales.

Trunk

The tender core of the banana plant's trunk is also used in South Asian and Southeast Asian cuisine, and notably in the Burmese dish mohinga.

Nutrition and research

Bananas are an excellent source of vitamin B₆, soluble fibre, and contain moderate amounts of vitamin C, manganese and potassium. Along with other fruits and vegetables, consumption of bananas may be associated with a reduced risk of colorectal cancer and in women, breast cancer and renal cell carcinoma. Banana ingestion may affect dopamine production in people deficient in the amino acid tyrosine, a dopamine precursor present in bananas. Individuals with a latex allergy may experience a reaction to bananas.

Fibre

Textiles

The banana plant has long been a source of fibre for high quality textiles. In Japan, banana cultivation for clothing and household use dates back to at least the 13th century. In the Japanese system, 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.

In a Nepalese system the trunk is harvested instead, and small pieces are subjected to a softening process, mechanical fibre extraction, bleaching and drying. After that, the fibers are sent to the Kathmandu Valley for use in rugs with a silk-like texture. These banana fibre rugs are woven by traditional Nepalese hand-knotting methods, and are sold RugMark certified.

In South Indian state of Tamil Nadu after harvesting for fruit the trunk (outer layer of the shoot) is made into fine thread used in making of flower garlands instead of thread.

Paper

Banana fibre is used in the production of banana paper. Banana paper is made from two different parts: the bark of the banana plant, mainly used for artistic purposes, or from the fibers of the stem and non-usable fruits. The paper is either hand-made or by industrial process.

Cultural roles

Arts

• 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.

• A person slipping on a banana peel has been a staple of physical comedy for generations. A 1910 USA comedy recording features a popular character of the time, "Uncle Josh", claiming to describe his own such incident:

Now I don't think much of the man that throws a banana peelin' on the sidewalk, and I don't think much of the banana peel that throws a man on the sidewalk neither ... my foot hit the bananer peelin' and I went up in the air, and I come down ker-plunk, jist as I was pickin' myself up a little boy come runnin' across the street ... he says, "Oh mister, won't you please do that agin? My little brother didn't see you do it."

• The poet Bashō is named after the Japanese word for a banana plant. 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.
• The cover artwork for the 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 phallic banana on the inside.

Religion and popular beliefs

In Burma, bunches of green bananas surrounding a green coconut in a tray form an important part of traditional offerings to the Buddha and the Nats.

In all the important festivals and occasions of Hindus the serving of bananas plays a prominent part. The banana (Tamil:வாழை or வாழைப்பழம்) is one of three fruits with this significance, the others being mango and jack fruit.. It is also worth mentioning that ancient Tamils have named three varieties of bananas after Hindu Trinity of Gods Brahma, Vishnu and Shiva as Poovan Pazham- பூவன் பழம் (Brahma), Mondan/Mukundhan Pazham- மொந்தன்(முகுந்தன் பழம்) Vishnu and Peyan Pazham- பேயன் பழம் (Shiva).

In Thailand it is believed that a certain type of banana trees may be inhabited by a spirit, Nang Tani ( Thai: นางตานี), a type of ghost related to trees that manifests itself as a young woman. Often people tie a length of colored satin cloth around the trunk of the banana tree.

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

Other uses

• Banana sap from the pseudostem, peelings or flesh may be sufficiently sticky for adhesive uses.
• The large leaves may be used as umbrellas.
• Banana peel may have capability to extract heavy metal contamination from river water, similar to other purification materials.
• Banana peel has displayed antioxidant activity in vitro, especially from unripe extracts.