Musa
Sp. Pl. 2: 1043. 1753; Gen. Pl. ed. 5; 466, 1754.
Underground stems (corms) rhizomatous, short, pseudostems clustered, [0.5–]3–10 m. Leaf blades unlobed (older leaves often split to midrib), oblong or oblong-elliptic, [0.6–]2–3 × 0.3–0.6 m. Inflorescences pendent [erect]; pistillate flowers crowded, numerous; bracts of staminate flowers imbricate, forming budlike mass at apex of inflorescence. Berries cylindric, usually ± curved, weakly angled in cross section, [10–]20–35 cm, soft, fleshy. x = 10, 11.
Distribution
Asia (India to Japan and Indonesia), Australia (Queensland), Pacific Islands (and Oceania), often persisting around gardens and plantations in North America, Mexico, West Indies, Central America, South America, Africa, Oceania Pacific Islands (Oceania).
Discussion
Species of Musa are very important economically throughout the wet tropics. The fruits of several species are edible; they may be sweet (bananas) or starchy (plantains), and may be eaten raw or cooked. Some species are important fiber sources, especially M. textilis Née (abacá or Manila-hemp), and others are grown as ornamentals in subtropical and tropical regions. In addition, the plants have many minor uses in the tropics: banana leaves are used for wrapping and various other purposes, and the corms, the interior of the pseudostems, and the buds of staminate flowers are eaten as vegetables. Bananas used in North America are almost always sweet-fruited cultivars, imported from Central America to be eaten raw or used in cooking.
Prior to 1948, the taxonomy of cultivated bananas was not understood. Since then, it has become clear that most of the cultivated bananas are parthenocarpic diploids, triploids, and tetraploids (2n = 22, 33, 44) derived either from Musa acuminata Colla, M. balbisiana Colla, or hybrids between them (M. × paradisiaca Linnaeus). The most common crop bananas in North and Central America are triploid races of M. acuminata (genotype AAA) and triploid M. × paradisiaca with two sets of chromosomes from M. acuminata and one from M. balbisiana (genotype AAB). Those two types are very similar morphologically; distinguishing them reliably requires numerical scoring of a large number of characters from the pseudostem, petiole, peduncle, bracts of staminate flowers, and staminate and pistillate flowers (N. W. Simmonds and K. Shepherd 1955), many of which are very difficult to score on herbarium material. The ranges given below, based on herbarium specimens, are tentative, and need to be checked in the field.
Species ca. 30 (1 species and 1 stable hybrid in the flora).
Selected References
Lower Taxa
Key
1 | Bracts of staminate flowers lanceolate or narrowly ovate, apex acute, abaxial surface yellow, red, or dull purple, adaxial surface yellow proximally, often yellow or dull purple distally; perianth of staminate flower white or cream. | Musa acuminata |
1 | Bracts of staminate flowers lanceolate to ovate, apex acute or broadly acute, abaxial surface purple, adaxial surface reddish purple or crimson; perianth of staminate flower white, cream, or pink | Musa paradisiaca |