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In this article we will discuss about the Classification of Scitaminae. According to Engler and Prantl, Scitaminae consists of four families:- 1. Musaceae 2. Gingiberaceae 3. Cannaceae 4. Marantaceae.
Family # 1. Musaceae:
Musaceae are large herbs with a perennial rhizome, rarely trees with a woody un-branched trunk. Leaves are large, 2-ranked or spirally arranged, pinnately veined and with a blunt apex, having a long broad sheath and a stout, channeled petiole. Inflorescence terminal or axillary, a cymose panicle or a cincinnus.
The flower clusters are subtended by green or coloured spathes which are often caducous. Flowers zygomorphic, hermaphrodite or unisexual, epigynous and often showy. Perianth-segments 6 in 2 whorls, similar or distinguished into two series, free or coherent, imbricate, greenish or coloured.
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Fertile stamens five, rarely six or the sixth one is a staminode, in 2 whorls, free; anthers 2-celled, linear. Ovary inferior, trilocular; ovules many on axile placentation, anatropous, rarely ovule solitary in each cell and basal; style simple; stigma capitate or lobed; nectar-secreting glands often present on the septa.
Fruit a berry or capsule; seeds usually with hard testa, with copious or scanty endosperm or with perisperm only and straight embryo; endosperm or perisperm mealy; sucker disc-or cup-shaped.
Musa has a pseudostem which may be as tall as 4 mtr and is composed merely of the long, stiff and spongy leaf-sheaths rolled round one another. The leaves are spirally arranged on the underground large conical rhizome and the blades are crowded in a whorl at the top of the pseudostem; the petiole is long, stout and spongy.
At flowering time the aerial stem pushes through the centre of the leaf sheaths bearing one or 2 smaller leaves and terminating in a compound spadix which stands erect or bends down. The large caducous coloured bracts are also spirally arranged like the leaves.
Ravenala and some species of Strelitzia have a woody palm-like trunk. In other cases a few long-petioled leaves arise from an underground rhizome. The leaves are in 2 rows in Ravenala and other genera. In Ravenala there are several cincinnus inflorescence which are axillary, each subtended by a spathe.
In Strelitzia there is only one cincinnus with a large spathe. In Helicoina the spadix is terminal with several bracts arranged in 2 rows. Each bract subtends a cincinnus. In Musa the sepals and 2 lateral petals are united near the base, while the median petal is free and much smaller. In Ravenala sepals and petals are free and equal, the median petal is slightly smaller.
In Strelitzia the sepals are free, while the 2 lateral petals are united to form a broad winged, arrow-shaped structure. The other petal is short and broad. In Heliconia the median petal is free and very small while the sepals and other 2 petals are more or less coherent.
There are 6 perfect stamens in Ravenala. In other genera 5 stamens are fertile, the sixth is absent or reduced to staminode, often petaloid. In Heliconia a single basal ovule is present in each cell while in other genera there are many ovules on axile placentation.
The genus Lowia of the subfamily Lowioideae has an axillary peduncle rising from the rhizome. Flowers few or solitary not subtended by a spathe but bracteate. The calyx is cup-shaped and 3-lobed. The lateral petals are smaller while the median petal forms a large coloured lip and alters its position due to resupination.
Stamens are five with 2-celled anthers without any staminode; pollens granular. Ovules numerous in each cell of ovary; stigma deeply 3-lobed and the lobes are laciniate, seeds with 3-lobed aril.
The family is subdivided into 3 subfamilies, viz.:
I. Musoideae: Leaves spirally arranged; spadix terminal.
II. Strelitzioideae: Leaves distichous; spadix cincinnus type, axillary.
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III. Lowioideae: Leaves distichous; cyme one- or few-flowered on axillary peduncle.
The 3 subfamilies have been raised to the rank of distinct families by Hutchinson as Musaceae, Strelitziaceae and Lowiaceae, included in the order Zinziberales. This treatment of Hutchinson is supported by all subsequent botanists,
The family includes 6 genera and a little over 100 species in the tropical countries with a few in S. Africa and Madagascar.
The edible bananas that are available in India fall into 2 species, viz. Musa acuminata Golla which includes the varieties Basrai or Kabuli (Dwarf Cavendish), Harichal or Singapuri (Giant Cavendish) and Lai Kela or Red Banana, and Musa X paradisiaca Linn, which includes Champa or Mysore, Martaban, Kanthali or Silk and Kanchkela or Bluggoe; Musa acuminata is a good species while the other one is a natural hybrid.
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Musa textilis Linn, of the Philippines yields good fibre known as the Manila hemp. Several species of Musa are cultivated as ornamental plants. Species of Ravenala, Heliconia and Strelitzia are also cultivated as garden ornamentals. R. madagascariensis Gmel is the Traveller’s tree. Heliconia and Strelitzia have beautiful large flowers.
Family # 2. Gingiberaceae:
Gingiberaceae are annual or perennial aromatic herbs with underground rhizome and with or without aerial stems; rhizome creeping or horizontal or tuberous. Leaves are radical or cauline, alternate or opposite, usually distichous, with a sheathing petiole, ligulate; midrib prominent; secondary veins parallel or reticulate.
Flowers hermaphrodite in racemes or spikes, axillary or terminal, often on a distinct scape, rarely corymbose, strongly zygomorphic, subtended by one or more bracts or spathes.
Sepals 3. Petals 3, united below in a tube. Androecium of 2 whorls of stamen and staminodes; only one stamen of the inner whorl is fertile, other 2 of the same whorl and all 3 of the outerwhorl are modified into large petaloid staminodes; the filament of the perfect stamen is broad and grooved; anther 2-locular.
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Ovary inferior, 3-celled; ovules many on axile placentation; style passing through the groove of fertile stamen, undivided or 2-lipped or dentate; ovary rarely 1-celled with parietal or basal placentas. A pair of epigynous glands are present that secrete nectar.
In Costus there are septal glands instead of epigynous glands. Fruit fleshy and indehiscent or loculicidally 3-valved capsule. Seeds round or angular, mostly covered with large divided aril; perisperm copious with scanty endosperm and straight embryo.
The flowers are pollinated by insects which are attracted by the showy flowers and the nectar. In Globba the inflorescence bears in the axils of lower bracts small bulbils instead of flowers; these fall to the ground and grow into new plants.
The family includes 47 genera and over 1100 species. These are found in tropical countries of the world but the majority is Indo-Malayan. A few grow as far north as Japan and one in Australia.
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The family is subdivided into 2 subfamilies, viz.:
I. Subf. Zingiberoideae: All parts aromatic, leaves in 2 rows, nectaries present.
II. Subf. Gostoideoe: The rhizome only is aromatic, leaves spiral, nectaries replaced by septal glands.
The family is closely related to Musaceae in habit, in zygomorphic flowers and inferior ovary. It is, however, considered to be more advanced due to reduction in the androecium. Both Takhtajan and Cronquist raise the subfamily Costoideoe to the rank of distinct family viz.—Costaceae.
The family is very important for the economic plants it includes. Many have medicinal properties while others produce spices and condiments. Zingiber officinale Rose., is the ginger; Z- zerumbet Smith is also used as spice.
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Curcuma domestica Wall, is the turmeric (Haldi), C. angustifolia Roxb. is the East Indian Arrow-root, the rhizomatous tuber of which yields starch like that of Maranta arundinacea Linn, the true Arrow-root. C. amada Roxb. is used to flavour chutnies. C. zedoaria Rose, yields starch and is called the Shati food of Bangladesh.
Alpinia allughas Rose, and A. galanga Sw. are medicinal. Amomum subulatum Roxb. is the Bara Elachi, while A. aromaticum Roxb. is Morung Elachi. Elettaria cardamomum Linn, is the cardamon or Chhod Elachi. Costus speciosus Smith is the Mahabari Bach, the rhizome of which has medicinal properties.
Many are cultivated in the gardens for the beauty of the flowers and different species of llcdychium are favourites. H. coronarium Koenig is the Dulal Champa having large faint yellow very fragrant flowers. H. coccinium Buch.-Ham. has a long spike of bright red flowers growing in the hills of East India.
Kaempferia rotunda L. and K. linearis Wall, are called Bhuin Champa. Mantisia saltatoria Sims, the Dancing Girl has a lax inflorescence the flowers of which are almost always moving by the lightest touch of wind.
Family # 3. Cannaceae:
Cannaceae are tall herbs with a perennial rhizome. Leaves are large, alternate, pinnately veined, with prominent midrib and sheathing petiole. Flowers hermaphrodite, zygomorphic bracteate, in terminal spike or panicle. Sepals free, often scarious, imbricate. Petals united below in a tube, brightly coloured and subequal, adnate to the staminal column, imbricate.
The androecium consists of a petaloid stamen with half anther on the margin and 5 petaloid staminodes of which 3 outer imbricate, 2 inner more or less connate. Ovary inferior, 3-locular, with 2 series of anatropous ovules in each chamber on axile placentas; style petaloid, sdgma oblique. Fruit a capsule, with a fibrous, warty or weakly spinose pericarp; seeds many, rounded, with copious hard perisperm and a straight embryo.
Cannaceae is a monotypic family with about 50 species, mainly in tropical America. Canna indica Linn, with many varieties are grown in gardens while one with small scarlet flower is found wild in eastern India. C. orientalis Rose, is another species much cultivated in Indian gardens.
Many species contain large quantities of starch in the rhizome and Canna edulis K.G. is cultivated for that purpose. The family is closely related to Zingiberaceae from which it differs in not having a ligule and the fertile stamen having l-locular anther.
Family # 4. Marantaceae:
Marantaceae are perennial herbs with a syrtipodial rhizome, often stoloniferous; aerial shoots often branching. Leaves are distichous or spiral, with an open sheath, a terete and often winged petiole and a blade which is oblique at base; a pulvinus is present at the apex of the petiole.
Spikes or rarely panicle terminal or on distinct scape, bracteate; flowers hermaphrodite, zygomorphic and epigynous. Calyx of 3 sepals. Petals 3, united below in a tube with 3 unequal lobes.
Outer whorl of stamens entirely suppressed or only 2 or 1 is present modified as staminode; the posterior stamen of the inner whorl bears only a unilocular anther on one side; the lateral stamens are modified to petaloid staminodes one of which is hooded and encloses the style and stigma while the other is broad and flat.
Ovary 3-celled with only one basal ovule in each chamber; style stout, often involute or dilated at the apex; rarely ovary 1-celled. Fruit fleshy or a loculicidal capsule; seeds often arillate, with copious perisperm surrounding the curved or folded embryo.
Septal glands secrete nectar that collects in the lower part of the tube. Insects visit the flowers in search of nectar and pollinate them. The family contains 27 genera and about 300 species mostly in tropical America. Maranta arundinacea L. is the Arrow-root, indigenous to West Indies but is now cultivated in many tropical countries.
Donax arundiastrum Low of eastern India and Malaya is the Mukta-pati or Shital-pati plant, the strips of the polished bark of which are woven into mats. A few others are cultivated in gardens as ornamental plants.
The family is closely related to the other families of Scitiminae and particularly to Cannaceae from which it differs in having solitary ovule in the ovary-chambers, involute or dilated style and curved or folded embryo. It is considered to be most advanced in this group having only 1 fertile stamen with half anther and solitary ovule in the cells of the ovary which again is frequently 1-celled.
K. Schumann subdivides the family into 2 tribes, viz.:
Tribe I, Phrynieae: Ovary trilocular.
Tribe II, Maranteae: Ovary unilocular.
