The family comprises of about 500 genera and 4500 species including such as Avena sativa (Oat – Jai, Barley) commonly distributed in temperate region, but are also found in tropical and sub-trope! Areas. in Pakistan family is represented by many crop plants such as: Triticum aestivum (Wheat), Oryza sativa (rice), Hordeum vulgare (barley), Zea mays (maize), Sorghum vulgare (jowar), Avena sativa (oat). Saccharum officinarum (sugar-cane); and grasses like: Poa, Festuca, Andropogan, Cynodon, Cymbopogan, etc.
The representative species is Avena sativa (barley).
Avena sativa (Oat – Jai)
It is a cultivated herb.
Adventitious, fibrous root
Erect, cylindrical, distinct node and internodes, node swollen; fistular.
Cauline and ramal, exstiputate, alternate, Simple, Ligulate, Venation: parallel, Leaf base sheathing.
Inflorescence, A panicle of spiketets. Each spikelet consists of two perfect and one terminal imperfect flower enclosed by two glumes.
Bracteate (bracts are represented by an inferior palea which bears a stiff hair. The Bracteolate (bracteoles are represented by a boat-shaped superior palea). Incomplete, Zygomorphic, Bisexual, Hypogynous.
Seed Structure of Avena sativa (Oat – jai) along with its different parts are as follow
Represented by two-minute scary lodicules borne on a short axis within the two paleae.
3 stamens, Polyandrous, Filament bong, Anthers: versatile, inferior.
Monocarpellary, Ovary: superior with a single basal ovule, Placentation: basal, Style short, Stigma: two and feathery.
P2 lodicules, A3 G1
Economic Importance of Family
Most of the plants i.e., cereal crops provide food for man.
- The dried stem and leaves of the cereal crops yield toori, which is used as fodder for the cattle. Dried grass or hay is also similarly used.
- Sugar, Gur and Shakar are obtained from the sweet juice obtained from the stem of sugar cane of which there are several varieties.
- Paper is manufactured from certain species of grasses, and bamboos.
- Bamboo are used as building material for scaffolding, thatching huts, making boats, carts, pipes etc., and the split are woven into mats, basket, fans, hats, coarse umbrellas, ropes and brushes.
- Leaves of bamboo are also given to horses as a cure for cough and cold etc. The young shoots are often pickled and the seeds are also eaten by poor class of people. A white siliceous substance known as Tabasir deposited near the joints is given to children as a tonic and astringent.
- Certain grasses yield fragrant oils, medicine, e.g., Vitiveria zizandoides and Andropogon squarrosus (Khas), yield the oil-bearing vetiver roots; Cymbopogon citrates (lemon-grass), yield the lemon-grass oil; C. nardus is cultivated for its aromatic citronella oil; G. flexosus for lemon-grass oil; C. martini, geranium grass is the source of oil. Andropogon odoratus is the ginger-grass. The oil obtained from these plants are used in perfumes and soap industry.
- Spinifex littorcus is a useful sand-binder on the seashore.
- The stony bracts of Coix lachryma (Job’s tears) are strung in to necklace.
- Imperata cylindracea is the cotton grass.
- Rye is largely cultivated as its inflorescence when attacked by Claviceps purpurea, yield ergot from which ergotine, a drug for controlling uterine hemorrhage after child birth is extracted.