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*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 which are tightly rolled round each other to form a rigid bundle of 20-50 cm diameter. *New leaves originating from the corm grow up continuously through the centre of the pseudostem with their laminas tightly rolled.

The taxonomic nomenclature of the bananas presents some special problems. In the past several specific names have been given to taxa which are now known to be fairly well-defined hybrid groups or even just cultivars. The type species of the genus, ''[[Musa paradisiaca]]'' L., the French plantain, is such a hybrid and should correctly be written as ''M.'' × ''paradisiaca'' L. or as ''Musa'' (AAB group) since it is a triploid hybrid with 2 genome sets contributed by ''[[Musa acuminata]]'' and one by ''[[Musa balbisiana]]'' . The cultivar Dwarf Cavendish has been named ''M. cavendishii'' Lambert ex Paxton (synonyms ''M. sinensis'' Sweet ex Sagot, ''M. nana'' Lour.), but being a triploid with 3 sets of genomes of ''M. acuminata'' , can be more clearly identified as ''Musa'' (AAA group) "Dwarf Cavendish". ''Musa chiliocarpa'' Backer is a hybrid belonging to ''M.'' × ''paradisiaca'' L. or the ''Musa'' (AAB group).

Although they never found edible forms derived purely from ''M. balbisiana'', the existence of ''M. balbisiana'' forms BB and BBB is suggested by morphological studies using the scorecard score-card devised by Simmonds and Shepherd to determine the genome constellation of edible bananas on the basis of 15 distinguishing characters, mostly in the inflorescences. Some cultivars in the Philippines ("Saba", the most important cooking cv.; "Abuhon"), in Thailand ("Kluai Lep Chang Kut"), in Papua New Guinea ("Auko") and possibly in Indonesia and Malaysia (respectively "Pisang Kepok" and "Pisang Nipah") score the same as ''M. balbisiana'' . Moreover, isozyme banding patterns of the cultivars also appear to be identical to those of ''M. balbisiana''. The cultivars mentioned are triploid and may tentatively be classed in a BBB group.

Since a continuously high growth rate leads to high yield, banana is at its best in warm and humid tropical climates. However, the crop is so attractive that it is grown right up to its ecological limits, where the mean growth rate affords marginal yields. Temperature is a major factor. In none of the important production centres does the temperature drop below 15°C 15 °C for long; the optimum for growth is about 27°C 27 °C and the maximum 38°C38 °C. Chilling injury occurs below 13°C 13 °C and only "Mysore", "Dwarf Cavendish" and "Pome" tolerate temperatures near O°C0 °C. In the equatorial highlands the banana disappears at elevations above 1600 m.

Bananas are generally propagated by suckers. Sword leaf suckers are preferred since they bear larger bunches in the first crop (the "plant crop"). Corms or pieces of corms ("bits") are also used as planting material. They are usually pared and may be immersed in hot water (52°C52 °C) or a pesticide solution to kill nematodes and borers before planting. Recently, tissue culture for rapid propagation through disease-free shoot tips has been developed. This method is already employed commercially, but the occurrence of undesirable mutations is causing concern.

Banana needs large quantities of nutrients. Nutrient removal by a crop of 30 t/ha amounts to 50 kg N, 15 kg P₂O₅, 175 kg K₂O, 10 kg CaO and 25 kg MgO. In home gardens the application of manures and compost is recommended together with 0.25 kg of urea and muriate of potash every three months for each stool. Commercial plantations monitor the leaf nutrient level, sampling the third youngest leaf. The following levels - in dry matter percentage - are considered adequate: N 2.6, P₂O₅0.45, K₂O 4.0, CaO 1.40, and MgO 0.60.

In commercial plantations several other practices are carried out to sustain high productivity and ensure good quality fruit for the (export) market. These are desuckering, propping, removal of male buds, and bagging of the bunch. Every 6-12 weeks plants are desuckered to leave only the mother stem (bearing), a daughter (the follower) and - in the case of ratoons - a granddaughtergrand-daughter. At low density, each stool can carry 2 mother stems and 2 followers. Thus, to prevent overcrowding and to regulate the successive crops per stool, a follower is spared for each mother stem every 6-10 months (or more in cool climates) to bear the next bunch. Only healthy, deep-set suckers are spared. Props or ties provide additional support for the plants when the bunches appear; they prevent the plant from being toppled by the heavy weight of the bunch. The male bud is removed as soon as the last two hands of the bunch appear. At the same time, one or more hands may be removed to increase finger length in the remainder, and bunches may be bagged. The bags are polythene sleeves impregnated with insecticides; they are used to prevent fruit blemishes from insects, birds, dust, etc., and to raise the temperature of the bunch, advancing fruit growth, particularly in cooler climates.