In this article we will discuss about:- 1. General Features of the Moraceae 2. Floral Range in the Moraceae 3. Divisions 4. Number and Distribution 5. Commonly Occurring Plants 6. Economic Aspects.
General Features of the Moraceae:
Habit – Shrubs or trees, with milky sap.
Leaves – Alternate or opposite, simple, entire, stipulate.
Inflorescence – Heads, racemes, spikes, etc.
Flowers – Unisexual, 4-merous.
Perianth – Present, usually of 4 segments, free or united.
Androecium – Stamens equal in number and opposite to perianth segments; filaments inflexed or erect in bud; anthers 2-celled, versatile, dehiscing lengthwise.
Gynoecium – Carpels 2, often 1 abortive; ovary inferior or superior; ovule solitary, pendulous from apex.
Fruit – Multiple.
Seeds – Embryo curved, surrounded by a fleshy endosperm.
Floral Range in the Moraceae:
The inflorescence is fundamentally cymose, but it is often greatly modified. In Broussonetia, Cudrania and Maclura, the female inflorescence is a globose head. The union of pedicels and peduncles results in a laminate receptacle whose ventral surface is studded with minute sessile flowers, as in Dorstenia.
The cymes may coalesce to develop into a fleshy hollow axis, bearing flowers on the interior surface, e.g., Ficus. The inflorescence of Morus is condensed into a pendulous amentiferous structure.
The apparent spike inflorescence in Artocarpus is formed by fusion and coalescence of several fertile branches. The cauliflorous flowering buds arise exogenously on the young and endogenously in the old stems. Due to total shifting of flowering and fruiting to old limbs and the main trunk, the cauliflory existing in A. heterophyllus is believed to be of advanced type.
Pundir (1965) noted that the first crop of the syconia in Ficus glomerata is formed by axillary buds of the uppermost leaves. Some exogenously derived dormant buds become active and form the flowering shoots on old branches. Simultaneously, there starts the de novo production of secondary buds which are interpreted as endogenous. Of these, one becomes a leader and acts as a cauliflorous shoot.
Although the stamens are 4, the number is sometimes reduced to 1 or 2 (Artocarpus, Dorstenia, Ficus, Morus).
Of the two carpels, the hinder one is variously aborted. It is sometimes developed (Artocarpus) or sometimes not indicated (Chlorophora). It may be represented by an empty ovarian chamber, as in Morus. In many other genera, the presence of a hind carpel is shown only by a style resembling an anterior one.
Divisions of the Moraceae:
The Moraceae is divided into three subfamilies:
Subfamily I:
Artocarpoideae. Leaves spirally folded in bud. Stamens erect in bud. Ovule apical. Example: Artocarpus.
Subfamily II:
Conocephaloideae. Leaves spirally folded in bud. Stamens erect in bud. Ovule apical or basal, orthotropous. Example: Conocephalus.
Subfamily III:
Moroideae. Leaves not spirally folded in bud. Stamens inflexed in bud. Ovule apical. Example: Morus.
Number and Distribution of the Moraceae:
The Moraceae comprises 75 genera and about 3,000 species. They largely abound in the tropical regions, but a few spread over the temperate zone.
Commonly Occurring Plants of the Moraceae:
Sack Tree or Uppas Tree [Antiaris toxicaria (Pers.) Leschen.] is a stately gigantic glabrous tree whose trunk is buttressed.
Bread Fruit Tree [Artocarpus altilis (Park.) Fosberg] is a tree with pinnatifid leaves.
Chaplash (Artocarpus chaplasha Roxb.) is a large deciduous tree with globose or oblong inflorescence.
Jack fruit Tree (Artocarpus heterophyllus Lamk.) and Angeli Wood Tree (A. hirsutus Lamk.) are evergreen trees.
Conocephalus suaveolens Bl. is a large climber.
Cudrania cochinchinensis (Lour.) Kudo and Masam. ex. Sauer is a scandent shrub.
Banyan Tree (Ficus bengalensis L.), Indian Rubber Tree (F. elastica Roxb.) and Pipal Tree (F. religiosa L.) are large trees.
Ivy Fig (Ficus stipuilata Wall.) is an herbaceous plant which climbs on walls.
White Mulberry (Morus australis Poir.) is a moderate sized deciduous tree.
Phyllochlamys spinosa Burm. is a large spinous shrub.
Streblus asper Lour, is a small rigid scraggy evergreen tree.
Economic Aspects of the Moraceae:
The bark of Antiaris toxicaria is used for making garments and sacks; the stem juice is the source of an arrow poison. Edible fruits are derived from Artocarpus altilis, A. heterophyllus, A. lakoocha, Ficus carica, F. cunia, F. glomerata, F. hispida, F. sycomorus, Morus nigra, Treculia africana, etc. The wood of Artocarpus chaplasha, A. hirsuta, F. bengalensis and F. religiosa is employed for construction purposes.
Brosimum aubletii and Piratinera guianensis produce curiously streaked wood. The fruits of B. alicastrum (West Indies) are cooked and eaten. The latex of B. galactodendron (Cow Tree of Venezuela) is sweet and nutritious. Broussonetia papyri/era forms good fibres for manufacturing paper from the inner bark and is largely cultivated throughout Polynesia for making ‘tapa cloth’.
The latex of Castilla elastica forms ‘Panama rubber’ and C. ulei ‘Caucho rubber’, while that of F. elastica makes ‘Indian rubber’. Chlorophora excelsa yields valuable timber. ‘Fustic’, a natural yellow pigment, is extracted from C. tinctoria (tropical America). The roots of Conocephalus suaveolens are used for poulticing itch.
Dorstenia brasiliensis is a drug plant, the roots being used as a stimulant and tonic. Shellac is obtained from F. laccifera. The bark of F. nekbudu (Mozambique) serves as a source of ‘mutshu cloth’. The wood of Maclura aurantiaca is suitable for making bows. Morus australis is grown for the leaves which are fed to silkworms. The wood of Streblus asper is used for making small articles and cart wheels; the twigs are utilised as baits for catching prawns; the leaves serve as sand paper.
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