In this article we will discuss about:- 1. Characters of Marantaceae 2. Distribution of Marantaceae 3. Economic Importance.

Characters of Marantaceae:

Leaves 3-sectioned i.e., sheath, petiole, blade with the peculiar pulviniform ligule, unusual androecial condition with its several staminodes and solitary monothecous anther; 1-3 loculed ovary with a single apparently basal ovule in each fertile locule; the seed arillate with curved or folded embryo.

A. Vegetative characters:

Habit:

Perennial herbs or shrubs.

Root:

Adventitious.

Stem:

Acaulescent, rhizomatous rarely tuberous and sub-terranean.

Leaf:

alternate, petiolate, sheathing lamina usually linear, ovate, oblong or elliptic, pinnate, closely parallel, ligule or pulvinus-like swelling on the stalks; leaf distinguished into sheath, petiole and blade.

B. Floral characters:

Inflorescence:

Spikes or panicles sometimes scapose usually surrounded or subtended by a spathacous bract.

Flower:

Zygomorphic, hermaphrodite, epigynous, often in pairs at the axil of bracts.

Perianth:

Tepals 6, in two whorls of 3 each, usually differentiated into calyx and corolla.

Sepal:

3, free and imbricate.

Petal:

3, connate in an unequally lobed tubular corolla, the posterior corolla lobe is somewhat concave, lobes imbricate.

Androcium:

Stamens of outer whorl are represented by 1 or 2 petaloid staminodes or all the members completely suppressed; in the inner whorl the posterior median stamen as in Canna bear half anther, the other half anther lobe modified into a petaloid appendage, the remaining two lateral stamens of the inner whorl are modified into petaloid staminodes, of which one functions as a labellum and forms a hood over the stigma for time being ‘the staminode cocculatum.’

Gynoecium:

Carpels 3, syncarpous, ovary inferior, trilocular or unilocular (2 locules being often sterile), ovules 3 or 1 due to abortion of two other ovules, axile placentation; style 1, stout, flat, and twisted, lobed, involute or apically delated, the stigma 1, terminal turncate or depressed.

Fruit:

Loculicidal capsule or fleshy and berry like but dehiscent.

Seed:

Arillate with mealy perisperm, endospermic.

Pollination:

Entomophilous.

Floral formula:

Maranta Bicolor Ker

Distribution of Marantaceae:

Marantaceae or arrow root family represented by 26 genera and 350 species, distributed in the tropics and sub-tropics, but mostly plants of moist, or swamy forest habitats.

Economic Importance of Marantaceae:

1. Food:

The bulbs of Maranta arundinacea yield ‘commercial arrowroot’ a diet for children, due to presence of readily digestible starch.

The tubers of Calathea allouia (West Indies) are edible.

2. Mat:

The split stems of Clinogyne dichotoma are woven into mat.

3. Ornamentals:

Thallia dealbata, Phrynium are grown as ornamentals.

Common plants of the family:

1. Maranta arundinacea – Arrow-root.

2. Thallia – a popular garden aquatic.

3. Calathea alovia – common in W. Indies.

Division of the family and chief genera:

The Marantaceae is divided into 2 tribes viz.:

Tribe I: Phryneae:

Ovary trilocular, sometimes unilocular, each chamber one ovuled. Genera: Clinogyne, Phrynium etc.

Tribe II: Marantee:

Ovary unilocular, one ovuled only. Genus: Maranta.

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