1. Diagnostic features
- Mostly perennial herbs, small shrubs or sometimes climbers.
- Stem usually modified into bulbs, corms or rhizomes.
- Leaves radical or cauline, alternate or whorled.
- Inflorescence racemose, borne on long leafless scape.
- Flower small, bracteates bisexual, actinomorphic, hypogynous, trimerous.
- Tepal-6 in two whorls.
- Stamens 6 in two whorls, polyandrous, epipetalous.
- Gynoecium tricarpellary, syncarpous, trilocular, ovary superior, ovules numerous.
- Placentation axile.
- Fruit usually a capsule or sometimes berry.
- Cosmopolitan distribution.
- Mostly in warm temperate and tropical regions of the world.
3. Vegetative characters
- Mostly perennial herbs, rarely shrubs and trees (Dracaena, Yucca).
- The herbaceous members perenneate with the help of bulb (Allium), rhizome (Polygonatum) or corms (Colchicum).
- Some species grow growing in xerophytic conditions are Aloe, Agave,Yucca, etc.
- Adventitious root system.
- Sometimes thickened a tuberous to store food (Asparagus).
- May be aerial or underground.
- Aerial stems are erect or climbing (Gloriosa, Smilax), branched- branches modified into needle-like cladodes in Asparagus.
- Underground stem is modified into bulb (Allium), rhizome (Polygonatum), or corm (Colchicum).
- In some cases the stem shows secondary growth and become woody in Aloe, Yucca, Dracaena.
- Radical or cauline and ramal in Dracaena.
- Simple, exstipulate or stipulate, usually alternate, sometimes opposite (Scolypous) or whorled (Trillium).
- Usually sessile with sheathing leaf base.
- Venation parallel while reticulate in Smilax and Paris.
- The leaves are thick and succulent with spiny apex and margin (Aloe), scale like in Asparagus and Ruscus.
- The leaf tips are modified into tendrils in Gloriosa.
- Leaves are cylindrical in Allium.
- Only two leaves are present in Erythronium.
- Leaves are absent in Bowiea.
Image source: braincart
4. Floral characters
- Usually racemose- simple raceme (Aloe), terminal panicle (Yucca), umbel, spadix (Rhodea).
- Sometimes solitary terminal (Tulipa), solitary axillary (Gloriosa), condensed cyme (Allium), borne on a long leafless scape.
- Bracteate, complete, bisexual or rarely unisexual.
- Actinomorphic, sometimes zygomorphic (Howarthia), trimerous, rarely dimerous (Mainthemum), tetramerous (Aspidistra), hypogynous.
- Tepals-6, in two whorls (3+3).
- Usually gamopetalous or polypetalous (Lilium), rarely 8 (4+4) in Paris or 4 (2+2) in Mainthemum.
- Perianth tubular or campanulate (Aloe), bilabiate in Howarthia, usually petaloid.
- Sometimes sepaloid or differentiated into calyx and corolla (Trillium).
- Aestivation valvate or imbricate.
Image source: qsstudy
- Stamens usually 6 in two whorls (3+3), rarely 4 in Mainthemum, 3 in Ruscus, 8 in Paris or 9-12 in Tofieldia.
- polyandrous or rarely monadelphous (Ruscus), usually opposite to the tepals, epitepalous.
- Anthers 2-celled, basifixed or versatile, dehiscing by longitudinall slits or rarely by a terminal pore.
- The filaments are very short (Ophopgon), filiform i.e thread like in Asphodeelus, anthers extrose or introse.
- Usually tri-carpellary, syncarpous.
- Rarely 2 in Mainthemum, trilocular with many ovules in each locule.
- Placentation axile, ovary superior.
- Style simple and stigma trilobed.
- Usually a capsule (Aloe, Gloriosa) or a berry (Asparagus).
- Endospermic, embryo small.
h) General floral formula
- Allium cepa (onion), A. sativum (garlic), young fleshy shoots of Asparagus officinalis and tuberous roots of A. racemosus are used as vegetable.
- ‘Aloin ‘ is obtained from Aloe africana and A. barbedensis (Ghiukumari) used as laxative.
- The bulblets of garlic are used as antiseptic.
- Leaves of Aloe vera provide mucilaginous liquid used in piles and inflammation.
- Raw Allium cepa is used as in constipation, diarrhoea and cholera.
- Bulbs of Allium cepa and A. sativum and the roots of various species of Smilax are used as flavouring agents.
- Colchicine is obtained from Colchicum luteum, which is used to induce polyploidy.
- Dracaena provides a resinous juice, the dragon’s blood (D. cinnabari) is used in varnished and dyes.
- The leaves of Xanthorrhoea provide an acrid resin, which is used for making sealing wax, spirit, varnishes for coating metals.
- Phormium Texan (Flax), Yucca filamentosa (ketuke), Smilax glabra give excellent fibres.
- These fibres are used for cordage, fishing nets, mattings, twines , etc.
vii) Ornamental plants
- Asparagus, Agapanthus africanus, Gloriosa superba, Lilium candidum, Ruscus aculeatus, etc are well known garden plants.
Characteristics and economic importance of Liliaceae (Lily family)