The below mentioned article provides an overview on Family – Amarantnaceae. After reading this article you will learn about: 1. Explanation on Family – Amarantnaceae 2. Economic Importance of Family – Amarantnaceae.
Explanation on Family – Amarantnaceae:
There are about 64 genera and 800 species in this family.
Distribution:
The family is well represented in the tropical regions of the world. The plants are very commonly found in the tropics of New World, Africa and India. Some plants are also found in temperate regions. In our country and others, several species are cultivated as ornamental plants e.g., Celosia cristata (cockscomb), Amaranthus (foxtail), and Gomphrena globosa.
The family resembles Chenopodiaceae in several ways. From the point of view of its stem anatomy, the vascular bundles in the stem are arranged in several concentric rings or more or less irregularly like that the stem of the members of Chenopodiaceae. Biallon, the French botanist, however, united this family with Chenopodiaceae, because of these resemblances.
Habit:
The plants are herbs or shrubs. Mostly they are annual or perennial herbs. The trees are rare.
Leaves:
The leaves are generally opposite or alternate, simple, entire, exstipulate and usually covered with hairs.
Inflorescence:
Usually the inflorescence is of racemose type. This may be a simple or branched spike or a raceme. Mostly the small flowers are being arranged in dense fascicles, e.g., Amaranthus (foxtail) and Celosia cristata (cockscomb).
Sometimes the branching of the inflorescence takes place in the axil of the bracteoles of the flowers giving rise to dichasia, which may be borne on a simple or racemosely or cymosely branched main axis. In certain cases the lateral flowers are being aborted and on their place tufts of hair or prickles are developed which persist in the ripe fruit and help in dissemination.
Flower:
Usually the flowers are very minute and arranged in dense facicles, e.g., Celosia cristata (cockscomb) and Amaranthus (foxtail), etc. Each flower bears a pair of large membranous persistent bracteoles; which are sterile. The flower in its structure quite resembles to that of Chenopodiaceae.
Usually the flowers are bracteate and bracteolate, hermaphrodite, rarely unisexual by abortion, actinomorphic (regular) and hypogynous.
Perianth:
The perianth is dry, membranous and very often white or coloured. It consists of 4 or 5 perianth leaves. The perianth leaves are green and herbaceous. The membranous perianth leaves are free or more or less united. Sometimes they become hairy.
Androecium:
It consists of 4 or 5 stamens. They are situated opposite the perianth leaves. Usually the stamens are united at the base forming a membranous tube. Sometimes these stamens bear fringed outgrowths in between them. Mostly the anthers are two-celled but in certain cases they may become one celled. They dehisce longitudinally.
Gynoecium:
It consists of 2 or 3 carpels, syncarpous. The ovary is unilocular and superior. In Celosia and certain other allied genera there is a single basal ovule. Generally, the ovules are campylotropous. The styles are one, two or three.
Fruit:
The fruit is generally dry. This may be a nut, drupe or berry.
Seeds:
The seeds are endospermic usually having a rough or polished testa. The embryo is curved and lies close to the seed-coat.
Pollination:
Entomophily.
1. Achyranthes aspera Linn.; Verna. Chirchita, Latzira, Apmarg:
Habit:
Perennial herbs.
Root:
Tap and branched.
Stem:
Erect, herbaceous, quadrangular, branched, solid, green, and pubescent.
Leaf:
Cauline and ramal, opposite, exstipulate, simple, sub-sessile, ovate, entire, acute, unicostate reticulate, rough, coriaceous, hairy.
Inflorescence:
Racemose, spike.
Flower:
Bracteate, bracteolate, sessile, bracts and bracteoles, spinous and persistent, hermaphrodite, actinomorphic, regular, complete, pentamerous, hypogynous, cyclic.
Perianth:
5 tepals, polyphyllous, dry, membranous, white or coloured, hairy.
Androecium:
5 stamens, antetepalous, stamens alternated by fringed outgrowths, anthers dithecous, introrse, dehiscing longitudinally.
Gynoecium:
2, bicarpellary, syncarpous, ovary unilocular, superior, single basal ovule, style short, stigma bifid.
Fruit:
Dry, utricle.
2. Amaranthus spinosus Linn.; Verna. Jangli chaulai:
Habit:
A spiny herb.
Economic value:
The plants are used medicinally for piles, colic, boils, etc. It is pungent, purgative, diuretic and astringent. Roots are used for pyrrhoea. Also used in cough and fevers.
Root:
Tap and branched.
Stem:
Erect, aerial, branched, herbaceous, terete, solid, smooth, green.
Leaf:
Cauline and ramal, exstipulate, alternate, simple, petiolate, ovate, entire, acute, unicostate reticulate; 2 spines present in the axil which represent the modified axillary branch.
Inflorescence:
Spike.
Male Flower:
Bracteate, bracteolate, sessile, actmomorphic, unisexual, incomplete, staminate cyclic.
Perianth:
5 tepals, polytepalous, quimcuncial aestivation, membranous.
Androecium:
4-5 stamens, polyandrous, anteposed, filaments long, dithecous, versatile, introrse.
Economic value:
The root is used in eczema and colic. The boiled leaves and roots are given to children as laxative and applied as emollient poultice to abscesses, boils and bums. Plant is also used in snakebite.
Gynoecium:
Absent.
Female flower:
Bracteate, bracteolate, sessile, unisexual, incomplete, pistillate, actinomorphic, and cyclic.
Perianth:
5 tepals, polytepalous, quincuncial, membranous.
Androecium:
Absent.
Gynoecium:
2 carpels (bicarpellary), syncarpous, ovary superior, unilocular, single basal ovule, style short, stigma bifid and hairy.
Fruit:
Utricle.
Economic Importance of Family – Amarantnaceae:
The family is of little economic value. A few species are grown as ornamental plants.
A list of some plants is given here:
1. Amaranthus blitum var. oleracew, Eng.-Amaranth; Verna.-Chaulai-This is a herb, its leaves are used as vegetable.
2. Amaranthus spinosus; Eng.-Prickly Amaranth; Verna.-Kaiailchaulai-This is spiny herb. The ash of the leaves is used in dyeing. The roots possess medicinal properties and are used to cure eczema, colic and gonorrhoea. This is also used as vegetable and fodder.
3. Amaranthus caudatus; Syn. A. paniculatus; A. cruentus; Eng.-Valvet flower; Verna.- Ramdana-This is grown as a vegetable in North India. This is also grown as ornamental. It possesses dense red or golden coloured spikes.
4. Amaranthus tricolor, Syn. A gangeticus; Eng.-Amaranth; Verna.-Bari chaulai, lal sag- The leaves are used as vegetable. Cultivated in the Punjab, Assam, Maharashtra and Tamil Nadu.
5. Achyranthes aspera; Verna.-Chirchita, Latzira-This is a common weed with spike inflorescence. The plants are used medicinally for several diseases such as piles, colic, boils, etc. This is also used as an antidote for snake bite and scorpion sting.
6. Alternanthera amoena; Verna.-Kanchari-This is a herb, used as vegetable, cultivated in Bengal, Orissa and Tamil Nadu.
7. Aerva sp.-This is a perennial herb with red leaves. Used as edge plant to border the lawns.
8. Celosia cristata; Eng.-Cockscomb; Verna.-Morshikha-This is grown as an ornamental for its velvety inflorescence.
9. Digera muricata; Syn. D. arvensis; Achyranthes muricata; Verna.-Latmohuria-This is a herb. Its tender twigs and inflorescences are used as vegetable.
10. Gomphrena globosa-Grown as an ornamental for its beautiful globose violet inflorescences.
Systematic Relationships:
Hutchinson has placed the families Chenopodiaceae and Amarantaceae in his order the Chenopodiales. Bentham and Hooker included seven families in the series Curvembryae. These families are-Nyctagineae Illecebraceae, Amarantaceae, Chenopodiaceae, Phytolaccaceae, Batideae and Polygonaceae. Engler and Prantl have placed the single family Polygonaceae in the order-Polygonales.
They have included Chenopodiaceae, Amarantaceae and Nyctaginaceae in the order-Centrospermae. Bessey included the family Polygonaceae as an advanced taxon of his Caryophyllales. Hallier included the family in his Centrospermae. Hutchinson considered his order-Chenopodiales as reduced types of Caryophyllales. This is certain that Polygonales have been derived from Caryophyllaceous ancestors.