Family: Liliaceae (Lily Family)

Monocot Family

Family: Liliaceae (Lily Family)

Systematic position

Diagnostic Features

·           Perennial herbs often with bulbous stem / rhizomes.

·           Radical leaves.

·           Perianth showy.

·           Stamens six.

·           Ovary superior.

General Characters

Distribution: Liliaceae are fairly large family comprising about 15 genera and 550 species. Members of this family are widely distributed over most part of the world.

Habit: Mostly perennial herbs persisting by means of a sympodial rhizome (Polygonatum), by a bulb (Lilium) corm ( Colchicum), shrubby or tree like (Yucca and Dracaena ). Woody climbers, climbing with the help of stipular tendrils in Smilax. Trees in Xanthorrhoea, succulents in Aloe.

Note: Liliaceae of Bentham and Hooker included Allium, Gloriosa, Smilax, Asparagus, Scilla, Aloe, Dracaena etc. Now under APG, it includes only Lilium and Tulipa. All others are placed under different families.

Root: Adventitious and fibrous, and typically contractile.

Stem: Stems usually bulbous, rhizomatous in some, aerial, erect (Dracaena) or climbing (Smilax) in Ruscus the ultimate branches are modified into phylloclades, In Asparagus stem is modified into cladodes and the leaves are reduced to scales.

Leaf: Leaves are radical ( Lilium) or cauline (Dracaena), usually alternate, opposite (Gloriosa), sometimes fleshy and hollow, reduced to scales (Ruscus and Asparagus). The venation is parallel but in species of Smilax it is reticulate. Leaves are usually exstipulate, but in Smilax , two tendrils arise from the base of the leaf, which are considered modified stipules.

Inflorescence: Flowers are usually borne in simple or branched racemes (Asphodelus) spikes in Aloe, huge terminal panicle in Yucca, solitary and axillary in Gloriosa, solitary and terminal in Tulipa.

Flowers: Flowers are often showy, pedicellate, bracteate, usually ebracteolate except Dianella and Lilium, bisexual, actinomorphic, trimerous, hypogynous, rarely unisexual (Smilax) and are dioecious, rarely tetramerous (Maianthemum), slightly zygomorphic (Lilium) and hypogynous.

Perianth: Tepals 6 biseriate arranged in two whorls of 3 each, apotepalous or rarely syntepalous as in Aloe. Usually petaloid or sometimes sepaloid, odd tepal of the outer whorl is anterior in position, valvate or imbricate, tepals more than six in Paris quadrifolia.

Androecium: Stamens 6, arranged in 2 whorls of 3 each: rarely stamens are 3 (Ruscus),4 in Maianthemum, or up to 12, apostamenous, opposite to the tepals, sometimes epitepalous; filaments distinct or connate, anthers dithecous, basifixed or versatile, extrose, or intrese, dehiscing usually by vertical slit and sometimes by terminal pores; rarely synstamenous (Ruscus).

Gynoecium: Tricarpallary, syncarpous, the odd carpel usually anterior, ovary superior, trilocular, with 2 rows of numerous ovules on axile placextation; rarely unilocular with parietal placentation, style usually one; stigmas 1 or 3; rarely the ovary is inferior (Haemodorum), nectar – secreting septal glands are present in the ovary.

Fruit: Fruit usually a septicidal or loculicidal capsule or a berry as in Asparagus & Smilax.

Botanical description of Allium cepa

(In APG classification, Allium cepa is placed under the family Amaryllidaceae)

Habit: Perennial herb with bulb.

Root: Fibrous adventitious root system

Stem: Underground bulb

Leaf: a cluster of radical leaves emerges from the underground bulb, cylindrical and fleshy having sheathy leaf bases with parallel venation.

Inflorescence: Scapigerous i.e. the inflorescence axis (peduncle) arising from the ground bearing a cluster of flowers at its apex. Pedicels are of equal length, arising from the apex of the peduncle which brings all flowers at the same level.

Flower: Small, white, bracteate, ebrcteolate, pedicellate, complete, trimerous, actinomorphic and hypogynous. Flowers are protandrous.

Perianth: Tepals 6, white,arranged in two whorls of three each, syntepalous showing valvate aestivation.

Androecium: Stamens 6, arranged in two whorls of three each, epitepalous, apostamenous /free and opposite to tepals. Anthers dithecous, basifixed, introse, and dehiscing longitudinally.

Gynoecium: Tricarpellary and syncarpous. Ovary superior, trilocular with two ovules in each locule on axile placentation. Style simple, slender with simple stigma.

Fruit: A loculicidal capsule.

Seed: Endospermous

Floral Formula:

Economic importance of the family liliaceae