1. Characters of Amaranthaceae:
Plants mostly herbs, a few shrubs,
leaves exstipulate and simple; opposite
or alternate, hairy; flowers small,
incospicuous and usually with bracts
and bracteoles, actinomorphic,
arranged in spikes or racemes; perianth
2 to 5, uniseriate, green or coloured,
free or united; stamens 3 to 5 free,
dithecous, antiphyllous (opposite the
perianth segments); gynoecium bi or
tri-carpellary, unilocular with a single
basal ovule; fruit one seeded nutlet.
2. A. Vegetative characters:
Habit:
Mostly herbs, rarely shrubs or undershrubs (Deeringia), annual or perennial
(Bosia, Ptilotus).
Root:
A branched tap root.
Stem:
Aerial, herbaceous or woody, erect or straggling, cylindrical, or angular,
branched, solid, hairy, green or striped green.
Leaves:
Simple, alternate or opposite, petiolate, exstipulate, reddish in colour,
unicostate reticulate venation.
3. B. Floral characters:
Inflorescence:
Axillary or terminal spikes (Achyranthes, Digera). Some times in cymose
panicles.
Flower:
Bracteate, sessile or sub-sessile, bracteolate, bracteoles two, actinomorphic,
hermaphrodite or unisexual hypogynous, small inconspicuous, green or
variously coloured.
Perianth:
Usually five tepals, free or united, sometimes two or three (Amaranthus), dry
membranous, valvate or twisted, sometime, hairy, green or coloured, persistent,
inferior.
4. Androecium:
Stamens 5 or 3 (Amaranthus), free or united, staminodes sometimes present, introrse,
dithecous or monothecous (Alternanthera). In Achyranthes 5 fimbriated scales alternate
with 5 fertile stamens.
Gynoecium:
Bicarpellary, or tricarpellary; syncarpous, ovary superior, unilocular, usually one
campylotropous ovule; basal placentation; style short or filiform; stigma 2 or 3.
Fruit:
Dry one seeded achene or several seeded capsule or one to several seeded berry.
Seed:
Endospermic with polished testa, kidney-shaped embryo curved.
Pollination:
Mostly anemophilous and in some plants entomophilous.
6. Distribution of Amaranthaceae:
The family Amaranthaceae is commonly called ‘Amaranth family’. It is a small family
comprising 65 genera and 850 species which are chiefly represented in tropical and
temperate regions. In India it is represented by 50 species.
Economic Importance of Amaranthaceae:
The Amaranthaceae is of little economic importance.
Food:
Seeds of Amaranthus caudatus are edible. Amaranthus cruentus and A. frumentacea are
raised as cereals by primitive tribes in Tropical Asia. The leaves of Amaranthus viridis, A.
spinosus and A. tricolor are also used as vegetables.
Medicinal:
Achyranthes aspera is diuretic and purgative. Decoction of Aerua tomentosa is used to
remove swellings. The stem and leaves of Alternanthera are used in snake-bite. The flowers
and seeds of Digera muricata (syn. D. arvensis) are given for urinary discharges.
7. Dye:
Leaves of Bosia amherstiana yield a black dye. The fruit juice of Deeringia is a substitute for
red ink.
Weeds:
Some genera are weeds e.g. Amaranthus, Celosia, Digera, Achyranthes, Gomphrena etc.
Ornamentals:
Celosia cristata (Cockscomb), Gomphrena globosa (Globe amaranthus) are cultivated in
gardens.
Primitive characters:
Plants under-shrubs or shrubs (Bosia, Ptilotus).
Leaves simple and alternate.
Flowers actinomorphic, hypogynous and hermaphrodite.
Anthers dithecous.
Seeds endospermic.