Musa (PROSEA Vegetables)

Plant Resources of South-East Asia Introduction

List of species

Musa L.

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

Family: Musaceae

Chromosome number: x= 10, 11; 2n= 22 (most species); 2n= 20 (M. salaccensis); most edible fruit cultivars are triploid.

Major species and synonyms

• Musa acuminata Colla (AA genome, seeded), Mem. Accad. Sci. Torino 25: 394 (1820), synonyms: M. zebrina Van Houtte ex Planchon (1854/55), M. malaccensis Ridley (1893).

• Musa balbisiana Colla (BB genome, seeded), Mem. Accad. Sci. Torino 25: 384 (1820), synonym: M. brachycarpa Backer (1924).

• Musa halabanensis Meijer, Acta Bot. Neerl. 10: 250 (1961).

• Musa salaccensis Zoll., Syst. Verz. Ind. Archip. 1: 74 (1854).

• Musa L. (edible fruit cultivars).

Vernacular names

• Banana (En)
• Bananier (Fr)
• Indonesia/Malaysia: pisang
• Papua New Guinea: banana (Pidgin)
• Philippines: saging
• Burma: nget pyo thee
• Cambodia: cheek nam' vaa
• Laos: kwàyz
• Thailand: kluai
• Vietnam: chuối.

Origin and geographic distribution

The genus Musa L. has its origin in South and South-East Asia. M. acuminata is native to South-East Asia. M. balbisiana is native to the eastern part of India, but is now widely distributed in South-East Asia. These two wild diploid bananas with seeded inedible fruits are the major parents of most edible bananas. The other two wild species have very restricted distribution. M. halabanensis is confined to West Sumatra, and M. salaccensis to Sumatra and Java. The cultivated fruit bananas are pantropical.

Uses

The banana inflorescence is a much appreciated vegetable. It is the part still enclosed within protective bracts: sometimes the entire young inflorescence, but usually the "male bud" at the top of the infructescence which continues to produce male flowers but no fruits. The inner part is eaten raw with fried noodles, after boiling in water, or after roasting in hot ashes. It is common in Thai style hot sour soup. A change of boiling water is sometimes needed to lessen the astringent taste. The lower, soft inner part of the pseudostem is also eaten fresh or boiled with a capsicum sauce or in curries.

Ripe fruits of M. balbisiana are also sometimes used for vegetable dishes, after removal of the seeds.

Production and international trade

The inflorescence buds of the seeded bananas are collected from wild plants occurring in the forest, with the exception of M. balbisiana which is also occasionally raised in home gardens. The buds of a number of cultivars of the seedless edible bananas such as "Pisang Awak" (Musa ABB), "Bluggoe" (Musa ABB) and "Saba" (Musa BBB) are used for the same purpose. Banana inflorescences constitute a common market vegetable, but no production statistics are available.

Properties

The nutritional value of the inflorescence buds varies considerable with species, age and origin. 100 g fresh edible portion has been reported to contain: water 90.2 g, protein 1.2 g, fat 0.3 g, carbohydrates 7.1 g, Ca 30 mg, P 50 mg, Fe 0.1 mg. The energy value is about 150 kJ/100 g.

Botany

• Tree-like perennial herbs, 2-9 m tall, with a short underground stem (corm) from which short rhizomes grow to produce a clump of aerial shoots (suckers).
• Roots adventitious. Pseudostem consisting of overlapping leaf-sheaths which are tightly rolled round each other to form a rigid bundle.
• Leaf-blades oblong, 100-500 cm × 25-100 cm, with a strong midrib and well-marked pinnately arranged, parallel veins.
• One terminal inflorescence rises from each corm, extending through the centre of the pseudostem; it is a compound spike of flowers which are arranged in several groups, compact and conical when young; each group is enclosed in a large ovate, pointed, reddish bract; female flowers develop proximally, male flowers at the distal end of the inflorescence, in the middle neuter flowers are sometimes present; finally the mature infructescence bears hands of fruits, usually followed by a long bare axis formed by abscission of the male flowers and subtending bracts, and terminating in a growing point ("male bud") which continues to produce bracts and male flowers.
• Fruit a berry, subcylindrical, often curved, rounded or nearly 4-sided in cross-section, full of seeds in wild species, seedless in fruit cultivars.

• M. acuminata: inflorescence horizontal or pendulous, peduncle usually downy or hairy, male flowers not red, fruits subsessile, seeds compressed; extremely variable and at least 5 subspecies are distinguished.

• M. balbisiana: inflorescence horizontal or pendulous, peduncle glabrous, male flowers tinged with red, fruits long-pedicellate, seeds subglobose.

• M. halabanensis: large herb, up to 9 m tall, gigantic in all its parts with the exception of the very small globular seeds, 3-4 mm × 2-3 mm; it produces an abundant, sticky juice; male bud ovoid, 15-20 cm × 9-12 cm, dark violet.

• M. salaccensis: small herb, not more than 3 m tall, with erect inflorescence, the fruits arranged in one row instead of 2, with turbinate seeds; male bud ovoid, ca. 15 cm × 5-6 cm, light red-violet, tasting bitter.

Ecology

Bananas are plants of the tropical humid lowlands. However, they frequently occur up to altitudes of 1200 m, M. acuminata and M. halabanensis even up to 1800 m. In the wild they occur mainly in forests, on forest edges, in ravines and on water sides. Bananas are moisture-loving, and a monthly rainfall of 200 mm is considered optimal. The optimum temperature for growth is about 27 °C. Temperatures should not drop much below 15 °C and not exceed 35 °C. The best soils are deep friable loams with good drainage and aeration. Bananas are very sensitive to strong winds.

Agronomy

Bananas are generally propagated by suckers, but the wild bananas can also be propagated by seeds. These usually germinate in 3-4 weeks time. Pieces of corm can also be used as planting material. In the case of deliberate cultivation (mainly M. balbisiana) in home gardens, organic fertilizers are usually applied and earthing-up is frequently practised to improve the anchorage of the plants.

Normally, however, the inflorescences of seeded bananas are gathered from natural stands. If the fruits are not used at all (e.g. M. salaccensis) the inflorescence can be cut at any stage of development. If the fruits serve a purpose (e.g. ripe fruits of M. balbisiana) the "male buds" are cut as soon as the last two hands of the bunch have appeared. The outer bracts are usually removed, as they are more fibrous than the inner parts.

Genetic resources and breeding

South-East Asia is the centre of diversity of Musa. A regional collection of germplasm is being maintained at the Bureau of Plant Industry, Davao City, the Philippines. In addition, national collections are maintained in Malaysia (MARDI), Thailand (Kasetsart University), Indonesia (SOHRI) and the Philippines (UPLB). Most research is concentrated on selection and characterization of edible cultivars, and relatively little attention has been paid to the wild species.

Prospects

Banana inflorescences or "male buds" as a product of gathering from the wild will gradually disappear together with the natural stands of wild bananas. Cultivation for the sole purpose of the inflorescence is a waste of energy in view of the extremely low harvest index. Banana "male buds" only have a future as a by-product of banana fruit production, but the marketable volume is probably too small to take aspects of vegetable quality into consideration in selection work.

Literature

• Espino, R.R.C., Jamaluddin, S.H., Bechamas Silayoi & Nasution, R.E., 1991. Musa L. (edible cultivars). In: Verhey, E.W.M. & Coronel, R.E. (Editors): Plant resources of South-East Asia 2. Edible fruits and nuts. Pudoc/Prosea, Wageningen, the Netherlands. pp. 225-233.
• Meijer, W., 1961. Notes on wild species of Musa from Sumatra. Acta Botanica Neerlandica 10: 248-256.
• Ochse, J.J. & Bakhuizen van den Brink, R.C., 1980. Vegetables of the Dutch East Indies. 3rd English edition (translation of "Indische Groenten", 1931). Asher & Co., Amsterdam, the Netherlands. pp. 511-522.
• Simmonds, N.W., 1962. The evolution of bananas. Tropical Science Series. Longmans, London, United Kingdom. 170 pp.
• Stover, R.H. & Simmonds, N.W., 1987. Bananas. 3rd Edition. Tropical Agriculture Series. Longman, London, United Kingdom. 468 pp.

Authors

• R.E. Nasution