Musa (PROSEA Carbohydrates)

Plant Resources of South-East Asia Introduction

List of species

Musa L. (plantain and cooking banana)

Protologue: Sp. pl.: 1043 (1753), Gen. pl. ed. 5: 466 (1754).

Family: Musaceae

Chromosome number: x= 11 (all plantains are triploids, but diploid, triploid and tetrapoid cooking bananas occur)

Major taxa and synonyms

• Musa (AAB group & ABB group), synonyms: Musa paradisiaca L., Musa × paradisiaca L.

• Musa (BB group & BBB group), synonym: Musa balbisiana Colla (1820).

Vernacular names

• Plantain, cooking banana (En)
• Bananier plantain (Fr)
• Platano (Sp)
• Indonesia: pisang (general)
• Malaysia: pisang
• Papua New Guinea: banana
• Philippines: saging.
• Burma (Myanmar): nget-pyaw
• Cambodia: ché:k
• Laos: kwàyz khauz
• Thailand: kluai
• Vietnam: chuối.

Origin and geographic distribution

The greatest diversity in Musa germplasm is found in South-East Asia, the recognized centre of origin of bananas and plantains. Malesia is thought to be the primary centre for dessert bananas, whereas plantains and cooking bananas originated along the peripheral areas of the region, spreading eastward to the South Pacific and westward from India to Africa and hence to the warm regions of Latin America.

Plantains and cooking bananas are found wherever dessert bananas are grown. In western and central Africa and in some island countries in the Pacific, plantains are more common than dessert bananas. In certain areas in South-East Asia such as the Philippines, eastern Indonesia and Papua New Guinea, where the long dry season poses a problem for the production of dessert bananas, cooking banana cultivars predominate and serve as part of the staple diet, particularly among the poorer segments of society.

Uses

Plantains and cooking bananas flower and fruit the whole year round; therefore, there is little need to preserve and process fruits. The fruits are cooked green or just after ripening, and are immediately consumed. Boiling, roasting and frying are the simplest and most popular ways of preparing the fruit. The ease and speed of preparation contributes to their popularity. Whole bananas are boiled, but the fruits are peeled and sliced before frying. To roast bananas, the peel may be removed if a grill is used, but whole fruits may also be placed directly into a low fire or hot ashes.

Not all banana recipes are simple; hundreds of delicacies in Thailand, Malaysia, Indonesia and the Philippines require sophisticated techniques. Dried bananas and banana chips (crackers) are two of the more popular snack products that have found a niche in the export market and contribute to the foreign exchange earnings of some countries like Thailand and the Philippines. The cultivar "Saba" is used in the manufacture of banana chips in the Philippines, but plantain cultivars are preferred in Indonesia for the same purpose. Another very popular manufactured product using the cooking cultivar "Saba" is banana ketchup, which has replaced tomato ketchup in the Philippines because of its superior flavour and much lower cost. Products of minor importance made from cooking bananas include flour, jam and jelly, dried banana fritters and vinegar.

Although fruits are the primary product of bananas and plantains in human consumption, the male bud and the heart of the growing pseudostem are also eaten in many parts of South-East Asia. An interesting observation is the preference of consumers for the male bud of wild Musa balbisiana and of the cooking cultivar "Saba" (Philippines) or its equivalents (Indonesia, Malaysia, Thailand and Vietnam).

Bananas also play popular roles in cultural traditions of many South-East Asian countries. Whole plants, leaves, fruits and bracts are used as decorations during religious ceremonies, weddings and parties. The leaves of bananas, especially the thick leaves of triploid cultivars, are used as wrappers in cooking native delicacies. The cooked food is also served on banana leaves. The split pseudostems and leaves are used as a mulch in banana gardens and other orchards, or as temporary shade for transplanted seedlings. Leaf sheaths are used locally to make baskets and handbags.

Production and international trade

Bananas and plantains constitute the fourth most important global food commodity (after rice, wheat and milk) in terms of gross value of production. The high ranking is not due to the revenue generated by the international banana export trade (which is recognized as the most important fresh fruit export), but the real value is in the huge volume of fruit produced and consumed locally throughout the tropics. Only about 10% of the estimated 70 million t produced annually is exported. The export trade is almost exclusively made up of dessert bananas belonging to the Cavendish clones, whereas plantains and cooking bananas compete with dessert bananas in domestic markets. Unfortunately, production statistics on bananas do not differentiate dessert from cooking bananas (including plantains), but INIBAP (International Network for the Improvement of Banana and Plantain) estimates that plantains and cooking bananas comprise 40% of total world production and dessert bananas 42%. Highland bananas in East Africa, consumed either fresh or cooked, with significant volumes used in beer manufacture, make up the remaining 18%. Plantain, Musa (AAB group), predominates as the most important cooking type in Africa and Latin America, but not in South-East Asia. The great susceptibility of plantain cultivars to diseases and pests and to the occasional droughts in some areas of South-East Asia has caused farmers to shift to the culture of the hardy cooking banana cultivars belonging to Musa (ABB group) "Matavia" or "Bluggoe" and Musa (BBB group) "Saba". Only in Java (Indonesia) can one find plantain cultivars still rivalling the importance and popularity of cooking bananas.

Properties

Plantains and cooking bananas contain per 100 g edible portion: water 55-58 g, protein 1.2-1.6 g, fat 0.25-0.30 g, carbohydrates 34-35 g, fibre 6-7 g, ash 0.8 g. They are good sources of K, Mg, Ca, P and Fe as well as vitamins A and C. Their energy value is 540 kJ/100 g.

Compared to the fruits, the edible male buds contain more water (about 92%), less carbohydrates (7%) but similar protein and fat contents of 1.2% and 0.3%, respectively. Per 100 g edible portion, male buds contain: Ca 30 mg, P 50 mg and Fe 0.1 g. Their energy value is about 150 kJ/100 g.

Description

• Tree-like perennial herb, 2-9 m tall, with a short underground stem (corm) with buds, from which short rhizomes grow to produce a clump of aerial shoots (suckers) close to the parent plant. Roots adventitious, spreading 4-5 m laterally, descending to 75 cm, but mainly in the top 15 cm, forming a dense mat.
• Shoots cylindrical pseudostems of overlapping leaf sheaths, tightly rolled round each other, forming a rigid bundle of 20-50 cm diameter.
• New leaves originating from the corm growing up continuously through the centre of the pseudostem with their laminas tightly rolled; emerging leaf unfolding a large oblong blade, 150-400 cm × 70-100 cm, with a pronounced supporting midrib and wellmarked, pinnately arranged, parallel veins.
• One terminal inflorescence arising from each corm with axis (peduncle) extending through the centre of the pseudostem and bending down when exserted, being a compound spike with flowers arranged in several groups, compact and conical when young; each group consisting of two closely appressed rows of flowers, enclosed in a large ovate, pointed reddish bract; bract becoming reflexed when flowers develop and being shed when fruits start to develop; female flowers proximally, male flowers at distal end of inflorescence, sometimes neuter flowers in the middle; commonly 12-20 flowers per node, and usually 5-15 nodes with female flowers; bracts open in sequence (about 1 per day) from base to top while the peduncle elongates; mature infructescence about 50-150 cm long, bearing hands of fruits, followed by a long bare axis formed if - as in most cultivars - male flowers and subtending bracts abscise, terminating in a growing point ("male bud") which continues to produce bracts and male flowers.
• Female flower (about 10 cm long) with inferior ovary of 3 united carpels, roughly triangular in section, surmounted by a short perianth of 5 fused segments and 1 free segment, together forming a tube around style and sterile androecium; stigma 3lobed; staminodes 5; male flower about 6 cm long, stamens 5, rarely bearing pollen, pistillode small.
• Fruit berrylike, seedless, 6-35 cm × 2.5-5 cm, green, yellow or reddish, curved in plantains but straight in cooking bananas; each cluster of fruits at a node is a "hand" (2-15 per bunch) and each individual fruit is a "finger" (12-20 per "hand").

Growth and development

The underground rhizome is sympodial, producing lateral shoots called suckers. Suckers originate from buds on the upper portion of the corm. The rate of suckering differs among cultivars and determines the period between successive harvests. A characteristic of plantains is the strong dominance of the apical meristem of the mother plant. Sucker production is held back until flowers have initiated in the parent corm, but then many suckers sprout at the same time. Sucker production in cooking banana cultivars is regular and harvesting of ratoon crops is well-spaced.

A mature and healthy plant has a whorl of 8-12 leaves, with the outer and older leaves dying as new ones are produced. The plants produce a definite number of leaves, i.e. 30 in many cultivars. The successive leaves increase in size until shortly before flower emergence. The appearance of a flag leaf signals the end of vegetative growth and the start of flowering and fruiting in which the apical meristem expends itself. At fruit maturity, the whole bunch is harvested and the mother plant cut down. If left alone, it will slowly die and suckers will take over.

Other botanical information

The French plantain, Musa paradisiaca, was first described by Linnaeus in 1753 and served as the type species of the genus Musa. But recent studies have shown that plantains are triploid hybrids of two wild and seedy species, Musa acuminata Colla and M. balbisiana Colla. For a brief period, the scientific name of plantains was modified to Musa × paradisiaca L., but the original description was rather restrictive and could not adequately accommodate the great diversity of hybrid groups that occur in South-East Asia. This observation led to the wide acceptance of a classification scheme whereby Musa (AAB group) "French" plantain and Musa (ABB group) "Bluggoe" are widely accepted technical terms for the common cultivars of plantains and cooking bananas in Africa and Latin America. Cultivars belonging to Musa (AAB group) have two genomes from the M. acuminata parent and one genome from M. balbisiana , whereas Musa (ABB group) indicates that the cultivars have inherited two genomes from the M. balbisiana parent and only one genome from M. acuminata. A tetraploid (ABBB group) is common in Thailand. In South-East Asia, where the greatest diversity of bananas occurs (particularly cooking bananas), parthenocarpic diploid and triploid forms of pure M. balbisiana derivatives exist. Being seedless forms of the wild parent, these groups of hardy cultivars are classified by some banana taxonomists simply as M. balbisiana. Here, however, Musa (BBB group) "Saba" is applied to the subgroup of cooking bananas. The curators of banana germplasm collections in South-East Asia believe that a parallel evolutionary pattern occurred in the development of seedless and parthenocarpic forms: the diploid Musa (BB group) "Abuhon" and triploid Musa (BBB group) "Saba" among the M. balbisiana cultivars, are the evolutionary equivalents of the edible diploid and triploid forms of dessert bananas, typified as Musa (AA group) "Pisang Mas" and Musa (AAA group) "Pisang Ambon". The M. balbisiana genome is believed responsible for the vigour and hardiness of the hybrids.

The problem in the application of the technical terms for plantains and cooking bananas also exists in the vernacular names. In western and central Africa where the common starchy bananas belong to the plantain subgroup, Musa (AAB group), the use of the term plantain is clear and straightforward. In eastern Africa where the great majority of starchy bananas belong to Musa (ABB group), the popular term cooking banana includes the few plantain cultivars present in the region. In Latin America, the Spanish term "plátano" is confusing; it may refer to plantains, to dessert bananas only, or both, depending on the country.

In South-East Asia, the vernaculars "pisang", "saging", "kluai" and "chuoi" cover dessert bananas, cooking bananas and plantains. The term plantain is of foreign introduction; there is no equivalent in the local languages of the region. At first, the term was applied to all cooking bananas, including true plantains (the reverse of the situation in eastern Africa). Since the gross morphology of the two subgroups of bananas is quite distinct, this was found confusing and unacceptable. The application of the term is changing and the word plantain is presently restricted to a special group of bananas with long and slender fruits that remain starchy upon ripening and require some form of cooking for the fruits to become palatable. Included in the term is the classical "Horn" plantain with extra large fruits but with few hands and no male bud. The term is also used for the "False Horn" plantain which has more hands in a fruit bunch and a small male bud. The third subgroup, which is called "French" plantain, is the most common in Africa. It has large fruit bunches with medium-sized fingers, many hands and a well-developed male bud. In South-East Asia, two additional subgroups exist, the Asian plantains and the Pacific plantains. The Asian plantain typified by Musa (AAB group) "Laknao" is distinct from the "False Horn" and the "Bungaoisan" of the Philippines in having cream-coloured compound tepals, cream fruit pulp and dehiscent bracts. This is different from the common plantains in Africa and Latin America, which have orange-yellow tepals, orange-yellow pulp and persistent bracts. All other gross morphological characters are very similar. In fact, some roadside fruit vendors try to pass off the lower quality "Laknao" for the higher priced "Bungaoisan". The Pacific plantains actually originated in Papua New Guinea but spread to the Pacific islands following the path of Polynesian migrations. Three types are recognized: Maia Maole, Popoulo and Iholena. So, in South-East Asia, all plantains are bananas but not all bananas are plantains!

Ecology

Plantains and cooking bananas originated in the humid tropics and perform best under warm (27-30°C) and very wet (200-220 mm per month) conditions. The cooking banana cultivars can stand warmer and drier climates. The best soils are deep, friable loams with good drainage and aeration. High soil fertility and organic matter content are desirable. The crop tolerates pH values of 4.5-7.5. It is sensitive to typhoons which cause blow-downs.

Propagation and planting

The fruits are seedless and propagation is asexual; suckers are the primary propagation material used. Tissue culture is becoming popular as a means of disseminating disease-free materials.

Three production systems are common in South-East Asia: home gardens, mixed intercropping and commercial smallholder plantations. There are few large corporate plantations as those in Latin America specializing in the production and export of dessert bananas. Bananas are grown in the home gardens of virtually every farm in the region. A wide range of dessert and cooking banana cultivars are planted for home consumption, the choice depending on the family's quality preferences rather than on productivity. But in mixed intercropping systems and commercial plantations, selection of cultivars is dictated by market demands and productivity. Commercial plantations that specialize in plantains and cooking bananas grow them as sole crops. In mixed intercropping systems, they are grown as a nurse crop for shade-loving plants such as coffee and cacao, or grown under coconut trees. In Papua New Guinea, a traditional AA diploid banana is commonly used as temporary shade for cocoa, while a tough AAB triploid may be found planted under coconut in a permanent stand.

Husbandry

The crop receives minimal inputs in home gardens. The mats of banana are generally used as compost and the crop benefits from the decaying organic matter. In commercial plantations, weeding, fertilizing and crop protection practices are applied.

Diseases and pests

Plantains are very susceptible to black Sigatoka (Mycosphaerella fijiensis var. difformis) and require regular fungicidal sprays to prevent premature death of the foliage. Therefore, Asian farmers have shown strong preference for the hardy cooking bananas for staple food. But even these are not immune to diseases, as they succumb to Cordana leaf spot (Cordana musae), bugtok in the Philippines and blood disease in Indonesia caused by Pseudomonas solanacearum and P. celebense. The recent discovery of banana bract mosaic virus (BBMV) attacking "Saba" and "Cardaba" in the Philippines is causing concern. It is believed the virus is widespread but undetected in the region.

Plantain cultivars are also the favourite host of weevil borer (Cosmopolites sordidus). Cultivars "Saba" and "Cardaba" are also affected by root-knot nematode (Meloidogyne incognita) but are resistant to the burrowing nematode (Radopholus similis).

Harvesting

Some plantain cultivars mature and fruit within a year under favourable conditions but most cooking bananas, especially the pure M. balbisiana derivatives, take 18 months to harvest.

Yield

Yields can be very high, sometimes reaching 50 t/ha per year. However, average yields in home garden production are only from 8-30 t/ha per year.

Genetic resources

South-East Asia is host to major banana and plantain germplasm collections. The Regional Banana Germplasm Resource Centre in Davao, Philippines, is the most complete, with 80 distinct cultivars from the Philippines, 35 accessions from Thailand, 29 from Malaysia and 16 from Indonesia. It also has 148 clones from Papua New Guinea. The national collections in Malaysia (MARDI) and Thailand (Kasetsart University) have been classified, and whereas each varietal garden has more than 100 accessions, Malaysia lists 54 and Thailand 39 distinct cultivars. Indonesia has recently launched a nationwide banana and plantain collection and conservation programme and will rehabilitate its germplasm collection garden. Vietnam is building up its germplasm collection in Phu Ho Fruit Research Centre. The wealth of Musa germplasm found in Laloki Agricultural Research Station in Papua New Guinea deserves global support, as the materials found there include not only M. balbisiana, M. acuminata and their hybrids, but also M. schizocarpa Simmonds and their putative hybrids with M. acuminata which opens a new evolutionary pathway in the domestication of edible Musa.

Breeding

An unusual situation exists in banana and plantain breeding. Although the wealth of germplasm resources needed in breeding programmes is found in the centre of diversity in South-East Asia, all the major banana and plantain improvement programmes are located outside the region. The International Institute of Tropical Agriculture (IITA), which specializes in plantain breeding, is located in Nigeria. The Fundacion Hondureña de Investigacion Agricola (FHIA), which specializes in dessert banana breeding, is based in Honduras. Since all major diseases and pests such as Sigatoka, Fusarium and banana weevil borer co-evolved with the crop, the progenies of the breeding programmes are not subjected to the extreme disease pressures prevailing in South-East Asia. If it proves impossible to relocate the breeding centres, priority must be given to providing an early screening research facility in the region, for the benefit not only of South-East Asia, but for the entire international banana community. The Maroochy Horticultural Research Station, Nambour, Queensland, Australia, maintains 260 lines of Musa from Papua New Guinea in tissue culture. Nine lines have been selected for their resistance to black Sigatoka, fusarium wilt and nematodes. One highly resistant cultivar to black Sigatoka is currently used for breeding plantains in Belgium and Nigeria (IITA).

Prospects

The role of plantains and cooking bananas will remain important in South-East Asia. With increasing research facilities and germplasm collections, higher yielding and more disease-resistant cultivars will be developed.

Literature

• Bayeri, K.P., 1994. Preserving prodigious plantains. SPORE No 49. Bulletin of the Technical Centre for Agricultural and Rural Cooperation.
• Espino, R.R.C., Jamaluddin, S.H., Silayoi, B. & Nasution, R.E., 1991. Musa. In: Verheij, E.W.M. & Coronel, R.E. (Editors): Plant Resources of South-East Asia 2. Edible fruits and nuts. Pudoc/Prosea, Wageningen, the Netherlands. pp. 220-233.
• FAO, 1988. Root and tuber crops, plantains and bananas in developing countries. Technical Bulletin No 7. Food and Agriculture Organization (FAO), Rome, Italy. 83 pp.
• INIBAP, 1993. Annual Report 1992. International Network for the Improvement of Banana and Plantain (INIBAP), Parc Scientifique Agropolis, Montpellier, Cedex 5, France.
• Lebot, V., Aradhya, K.M., Manshandt, R. & Meilleur, B., 1993. Isozymes and classification of Pacific bananas and plantains. In: Ganry, J. (Editor): Breeding banana and plantain for resistance to diseases and pests. CIRAD-FLHOR, Montpellier, France.
• Simmonds, N.W. & Shepherd, K., 1955. The taxonomy and origins of the cultivated banana. Journal of the Linnean Society of Botany 55: 302-312.
• Stover, R.H. & Simmonds, N.W., 1987. Bananas. 3rd edition. Longman, Essex, United Kingdom. 468 pp.
• Swennen, R., 1990. Limits of morphotaxonomy: names and synonyms of plantains in Africa and elsewhere. In: Jarret, R.L. (Editor): Identification of genetic diversity in the genus Musa. International Network for the Improvement of Banana and Plantain (INIBAP), Montpellier, France.
• Tezenas du Montcel, H., 1985. Le bananier plantain. Editions Maisonneuve et Larose, Paris, France. 143 pp.
• Valmayor, R.V., Silayoi, B., Jamaluddin, S.H., Kusumo, S., Espino, R.R.C. & Pascua, O.C., 1991. Banana classification and commercial cultivars in South-East Asia. PCARRD Information Bulletin No 24. Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (PCARRD), Los Baños, Laguna, Philippines. 20 pp.

Authors

R.V. Valmayor & M.E. Wagih