Floral Formula of some Important Families
This includes major distinguishing features and important plants of the family with floral diagram and floral formula.
Fabaceae
It is distributed all over the world. This family was earlier called papilionoideae, a sub-family of family leguminosae.
Vegetative Characters
Habit : Trees, shrubs, herbs, climbers.
Root : Tap root system, roots with root nodules, branched. Root nodules contain nitrogen-fixing bacteria (Rhizobium).
Stem : Erect or climber.
Leaves : Alternate, rarely simple, generally pinnately compound, stipulate, leaf base pulvinate, venation reticulate, leaves or leaflets modified into tendrils.
Floral Characters
Inflorescence : Racemose
Flower : Bisexual, zygomorphic.
Calyx : Sepals five, gamosepalous, valvate/imbricate aestivation.
Corolla : Petal five, polypetalous, papilionaceous, consisting of a posterior standard, two lateral wings, two anterior ones forming a keel (enclosing stamens and pistil), vexillary aestivation.
Androecium : Ten, diadelphous, anther dithecous.
Gynoecium : Ovary superior, monocarpellary, unilocular with many ovules, style single, many ovules in two alternate rows.
Fruit : Legume
Seed : One to many, non-endospermic
Floral formula : % ⚥ K(5) C1+2+(2) A(9)+1 G1
Economic Importance
- Pulses : Gram, arhar, sem, moong, soyabean.
- Fodder : Trifolium, Sesbania, etc.
- Edible oil : Soyabean, groundnut, etc.
- Dyes : Indigofera
- Fibres : Sunhemp
- Ornamental : Lupin, sweet pea
- Medicines : Muliathi
Solanaceae
It is a large family, commonly called as the ‘potato family’. It is widely distributed in tropics, sub-tropics and temperate zone.
Vegetative Characters
Habit : Herbs, shrubs, small trees.
Root : Tap roots.
Stem : Herbaceous rarely woody, aerial, erect, cylindrical, solid, branched or hollow, hairy or glabrous (smooth), underground stem in potato (Solanum tuberosum).
Leaves : Alternate, simple, rarely pinnately compound, exstipulate, hairy, venation reticulate.
Floral Characters
Inflorescence : Solitary, axillary or cymose as in Solanum. omee
Flower : Bisexual, actinomorphic.
Calyx : Sepals five, united, persistent, valvate aestivation, gamosepalous.
Corolla : Petals five, gamopetalous, valvate aestivation.
Androecium : Stamens five, epipetalous, anthers bithecous.
Gynoecium : Bicarpellary, syncarpous, ovary superior with oblique septa, bilocular, placenta swollen with many ovules, placentation axile.
Fruit : A many seeded berry or capsule
Seed : Many, endospermous.
Floral formula:
Economic Importance:
- Food : Potato, tomato, brinjal.
- Spices : Chilli
- Tobacco : It comes from the dried and cured leaves of Nicotiana tabacum. It is a fumigatory plant
- Medicine : Belladonna, Ashwagandha
- Ornamental : Petunia
Liliaceae
It is commonly called ‘the lily family. The plants belonging to this family are monocotyledonous plants. They are widely distributed worldwide.
Vegetative Characters
Habit : Perennial herbs with underground bulbs, corms, rhizomes
Roots : Adventitious, fibrous.
Stem : Aerial or underground, herbaceous or woody.
Leaves : Mostly basal, alternate, linear, exstipulate with parallel venation.
Floral Characters
Inflorescence : Solitary/cymose, often umbellate clusters.
Flower : Bisexual, actinomorphic.
Perianth : Tepal six (3 + 3), often united into tube, valvate aestivation
Androecium : Stamen six, (3+ 3).
Gynoecium : Tricarpellary, syncarpous, Ovary superior, trilocular with many ovules, axile placentation.
Fruit : Capsule, rarely berry.
Seeds : Endospermous
Floral Formula:
Economic Importance:
- Food : Young shoots and root tubers of Asparagus species are cooked
- Medicines : Aloe is a source of medicine.
- Ornaments : Gloriosa and tulip.
- Colchicine : Colchicum autumnale yield colchicine which is used in doubling of chromosomes.
Family Gramineae (Poaceae) :
Most advanced family among monocots
(1) Inflorescence spike of spikelets (Triticum), panicle of spikelets (Avena).
(2) Flowers small, sessile, surrounded by two scales, lemma (fertile bract, inferior or outer palea) and palea (superior or inner palea). The lemma bears a long, stif process called awn.
(3) Flowers zygomorphic, incomplete, hypogynous
(4) Perianth represented by two or sometimes three lodicules.
(5) Androecium 3 or 6, polyandrous, versatile fixation of anthers.
(6) Monocarpellary, superior, unilocular ovary with basal placentation. Stigma is feathery.
(7) Fruit is caryopsis or nut (Dendrocalamus) or berry (Bambusa)
Floral Formula: Br%⚥P2A3G1
Important plants
(1) Avena sativa (Oat)
(2) Triticum aestivum (Wheat)
(3) Sorghum vulgare (Jowar)
(4) Pennisetum typhoides (Bajra)
(5) Saccharum officinalis (Sugarcane)
(6) Zea mays (Maize)
(7) Oryza sativa (Rice)
(8) Bambusa tulda (Bamboo)
(9) Secale cereale (Rye)
(10) Cymbopogon citratus (Lemon grass)