Families of Monocotyledons (With Diagram)

In this article we will discuss about the Families of Monocotyledons:- 1. LILIACEAE (The ‘Lily’ Family) 2. GRAMINEAE OR POACEAE (The Grass Family).

1. LILIACEAE (The ‘Lily’ Family):

Aids for ‘Field Identification’:

Perennial herbs, often forming corms, bulbs or rhizomes; perianth showy; floral part in 3s; stamens 6; ovary superior.

A. Asphodelus Tenuifolius (Vern. Piazi):

Habit:

An annual herb.

Root:

Fibrous, adventitious roots.

Stem:

Condensed, underground and reduced, fistular.

Leaf:

Radical, simple, exstipulate, sessile, leaf base sheathing, long, acicular, entire, acute, fleshy, hollow, multicostate parallel.

Inflorescence:

Racemose raceme with its flowers on erect, cylindrical, fleshy, long peduncle or scape.

Flower:

Bracteate, ebracteolate, pedicellate, complete, hermaphrodite, actinomorphic, trimerous, small, white.

Perianth:

Tepals 6, arranged in two whorls of 3 each, polyphyllous, petalloid, oblong, valvate, white, mid-rib brownish and ridged.

Androecium:

Stamens 6, arranged in two whorls of 3 each, polyandrous, epiphyllous, attached just opposite to each perianth lobe, filaments unequal and larger of outer whorl than that of inner whorl, dithecous, versatile, introrse, white.

Gynoecium:

Tricarpellary, syncarpous, superior, trilocular, two ovules in each locule, axile placentation, style filiform, stigma trifid and yellow.

Fruit:

A capsule.

Seed:

Endospermic.

Floral Formula:

Identification and Systematic Position:

2. GRAMINEAE OR POACEAE (The Grass Family):

Aids for Field Identification:

Herbs; stem (culm) with hollow internodes, terete; leaves mostly flat and 2-ranked, leaf sheath usually open; fruit caryopsis.

B. Triticum Aestivum L. (Wheat; Vern. Genhu):

Habit:

An annual cultivated, cereal crop.

Root:

Fibrous, adventitious.

Stem:

Herbaceous, erect, cylindrical, unbranched but rarely branched, nodes and internodes are very clear, fistular, rough and green.

Leaf:

Radical when young but cauline later on; simple, alternate, exstipulate, sessile, differentiating into a long blade and a sheathing leaf base covering the internode; a membranous ligule is present at the junction of blade and leaf base; linear to lanceolate, entire, acuminate; multicostate parallel venation.

Inflorescence:

Spike of spikelets. Each spikelet consists of a pair of glumes, many inferior palea or lemma, superior palea, and encloses the lodicules, stamens and gynoecium.

Flower:

Bracteate (lemma or inferior palea), bracteolate (superior palea), sessile, complete, hermaphrodite, zygomorphic, hypogynous, small and inconspicuous; lemma is prolonged into a long ‘awn’.

Perianth:

Reduced into two modified, fleshy, small and white antero-laterally placed structures called lodicules.