Bananas.org - clueless about my bananas

Morphology of the banana plant

The banana plant is a tree-like perennial herb. It is an herb because its aerial parts die down to the ground after the growing season and it is a perennial because an offshoot growing at the base of the plant, the sucker, replaces the mother plant. The mat, also called stool, is the term used to designate the mother plant and its suckers. What looks like a trunk is actually called a pseudostem.
The variability observed in morphological traits is used to characterize banana plants.

Root system

The root system's main functions are to absorb and conduct water, and transfer nutrients from the soil to the plant.
Bananas have a primary root system and an adventitious one. Primary roots originate from the surface of the central cylinder in the rhizome (below). Secondary and tertiary roots originate from the primary roots.

Rhizome

The true stem is underground. It is commonly referred to as a corm, and occasionally as a bulb, but the botanically correct term is rhizome.
The terminal growing point of the rhizome, the meristem, is a flattened dome from which the leaves, and eventually the inflorescence (further down), are formed.

Pseudostem

The part of the plant that looks like a trunk is actually a false stem, called pseudostem. The pseudostem is formed by the tightly packed overlapping leaf sheaths (see leaf below). Even though the pseudostem is very fleshy and consists mostly of water, it is quite sturdy and can support a bunch that weighs 50 kg or more.
The pseudostem continues to grow in height as the leaves emerge one after the other and reaches its maximum height when the inflorescence (further down) emerges at the top of the plant.
In the photo the floral stem is visible in the center of the pseudostem.

Sucker

A sucker is a lateral shoot that develops from the rhizome and usually emerges close to the mother plant. Other names for sucker are keiki (in Hawaii) and pup.
A sucker that has just emerged through the soil surface is called a peeper. A full grown sucker bearing foliage leaves (below) is called a maiden sucker.
Morphologically, there are two types of sucker: sword suckers (right on the photo), characterized by narrow leaves and a large rhizome, and water suckers (left on the photo), which have broad leaves and a small rhizome. Water suckers have a weak connection to the mother plant and as such will not develop into a strong plant.
The number of suckers produced varies with the type of cultivar. The sucker selected to replace the mother plant after fruiting is called the follower or ratoon.

Leaf

The leaf is the plant's main photosynthetic organ. The leaf is formed by the apical meristem and emerges from the center of the pseudostem as a rolled cylinder (see cigar leaf below). The distal end of the elongating leaf sheath contracts into a petiole, that is more or less open depending on the cultivar. The petiole becomes the midrib, which divides the blade into two lamina halves. The upper surface of the leaf is called adaxial while the lower one is called abaxial.
The first rudimentary leaves produced by a growing sucker are called scale leaves. Mature leaves that consist of sheath, petiole, midrib and blade are called foliage leaves.
Lamina veins run parallel to each other in a long S shape from midrib to margin. Veins do not branch, which results in leaves tearing easily.

Cigar leaf

The cigar leaf is a recently emerged leaf still rolled as a cylinder.
The lapse of time in which a leaf unfolds varies. Under favourable climatic conditions, it takes about seven days, but it can take up to 15 to 20 days under poor conditions.
The new leaf is tightly coiled, whitish, and particularly fragile.
The extension at the tip of the leaf is called the precursory appendage. After emergence, it withers and falls off.

Inflorescence

The inflorescence is a complex structure that includes the flowers that will develop into fruits. As the last leaves emerge, the growing point of the meristem starts producing the inflorescence, which undergoes much of its development before emergence. The developing flower stalk grows through the pseudostem until it emerges at the top of the plant.


At emergence the inflorescence is erect but soon starts pointing down, with the exception of Fei bananas.	The bract lifts, or curls up at the tip, exposing the female flowers that will develop into fruit. The flowers are arranged in clusters, the future hands.	The developing fruits start pointing upwards soon after emergence.	Some cultivars possess hermaphrodite flowers, also called neutral flowers.	The male flowers subtended by bracts are the last type of flowers to appear.

The female (pistillate) flowers appear first. In cultivated bananas, the
ovary develops into a seedless fruit by parthenocarpy (without being pollinated). As it lifts, the bract (a modified leaf) exposes the female flowers that are clustered at the nodes and develop into hands of fruit. The number of hands in the bunch depends on the number of female clusters in the inflorescence, and varies depending on the genotype and environmental conditions.
As the female flowers develop into fruit, the distal portion of the inflorescence elongates and produces clusters of male (staminate) flowers, each subtended by a bract. The male flowers in the male bud produce pollen that may or may not be sterile. A third type of flowers called hermaphrodite, or neutral, may be present on the rachis, the stalk between the female flowers and the male bud. They generally do not develop into fruit and their stamens do not produce pollen.

Peduncle
The peduncle is the stalk that supports the inflorescence and attaches it to the rhizome.

Bunch
The bunch is the descriptive term for all the fruits along the rachis. The individual fruit (also called fingers) are arranged in hands. The largest bunch, according to Guinness World Records, weighed in at 130 kg³.

Rachis
The rachis is the stalk of the inflorescence from the first fruit to the male bud. It can be bare or covered with persistent bracts. The scars on the rachis indicate where the bracts were attached. They are called nodes.

Male bud
The male bud contains the male flowers enclosed in their bracts. It is sometimes called the bell. As the fruits mature, the rachis and male bud continue to grow. In some cultivars, the male bud ceases to grow after the fruits have set and can be more or less exhausted by the time the bunch reaches maturity. The presence or absence of the male bud is one of the traits used to distinguish cultivars.

http://www.bananas.org/f2/links-help...tml#post223448

Morphology of banana plant | Promusa - Mobilizing banana science for sustainable livelihoods