BANANA PROPAGATION

FAMILY: Musaceae

SCIENTIFIC NAME: Musa sp.

ORIGIN: Asian tropics

DESCRIPTION :

The banana plant is a large perennial herb with leaf sheaths that form trunk-like pseudostems. The plant has 8 - 12 leaves that are up to 9 ft long and 2 ft wide. Root development may be extensive in loose soil in some cases up to 30 ft laterally. Other plant descriptions vary, it depends on the variety.

Flower development is initiated from the true stem underground (corm) 9 - 12 months after planting. The inflorescence (flower stalk) grows through the center of the pseudostem. Flowers develop in clusters and spiral around the main axis. In most cultivars, the female flowers are followed by a few "hands" of neuter flowers that have aborted ovaries and stamens. The neuter flowers are followed at the terminal ends by male flowers enclosed in bracts. The male flowers have functionalstamens but aborted ovaries.

The ovaries contained in the first (female) flowers grow rapidly, developing parthenocarpically (without pollination) into clusters of fruits, called hands.
Fruits mature in about 60 - 90 days after flowers first appear. Each bunch of fruits consists of variable numbers of "hands" along a central stem. Each "hand" consists of two transverse rows of fruits ("fingers").
The fruit quality is determined by size (finger length and thickness), evenness of ripening, freedom from blemishes and defects, and the arrangement of the clusters. Quality standards may differ in various markets.

PROPAGATION:

Propagation by division

Bananas and plantains(cultivar of Musa) are propagated vegetatively rather than sexually because nearly all cultivated varieties are seedless, and fruits develop parthenocarpically (in the absence of seed development). The principal method of banana propagation by small-holder farmers is divison of suckers or pups which arise from the base of the main stem or from the underground corm. Farmers from different regions prefer different size suckers for optimal planting material. Very small pups are called buttons. Large suckers are the preferred planting material. These are removed from vigorous clumps of banana trees with a spade when at least three feet tall, during warm months. Pups should not be taken until a clump has at least three to four large banana plants to anchor it. When the pup is taken the cut must be into the mother banana plant enough to obtain some roots. Plant close to the surface. Large leaves are cut off of the pup leaving only the youngest leaves or no leaves at all.

Tissue Culture

Micropropagation technique has been developed during the past two decades are now considered well established. (Banerjee and De Langhe 1985; Cronauer and Krikorian 1984; Israeli et al.,1995; Vulysteke 1989). It has played a role in plantain and banana improvement program world wide ( Rowe and Rosales 1996; Vulysteke et al., 1997). The rate of multiplication ranged from two to ten or more shoots or bud propagules per month, resulting in potential propagation rates of several thousands or millions of plants per year.

Such rates are several orders of magnitude greater than achievable through conventional propagation. Since it is very important to obtain clonal plants, direct regeneration pathways has always been adopted. However it is also important commercially that the technique employed should be cost effective. To achieve this objective high propagation rate through scalp techniques are used. In order to assess dwarf variants, regenerants from scalps are assessed with GA3 and PCR methods.

The tissue culture laboratory is also used to produce healthy banana plantlets from selected commercial varieties for distribution to farmers using material selected from international and local sources.
Tissue culture is the most rapid method of propagation of valuable disease-free material.

Minisetting

Minisetting is a rapid propagation techniques which is used to quickly and inexpensively produce plant material, whether it is banana plantlets or germinated seeds for yam production. Bananas produced in the laboratory can be subsequently rapidly multiplied using minisetting to make healthy plantlets available to farmers on a commercially significant scale.