NCERT 11TH STANDARD BIOLOGY – FLOWER FAMILIES , FLORAL FORMULAS
Fabaceae
This family was earlier called Papilionoideae, a subfamily of family Leguminosae. It is distributed all over the world.
Vegetative Characters
Trees, shrubs, herbs; root with root nodules
Stem: erect or climber
Leaves: alternate, pinnately compound or simple; leaf base, pulvinate; stipulate; venation reticulate.
Floral characters
Inflorescence: racemose
Flower: bisexual, zygomorphic
Calyx: sepals five, gamosepalous; valvate/imbricate aestivation
Corolla: petals 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, mono carpellary, unilocular with many ovules, style single
Fruit: legume; seed: one to many, non-endospermic
Floral Formula: % ⚥ K(5) C1+2+(2) A(9)+1G1
Economic importance
Many plants belonging to the family are sources of pulses (gram, arhar,sem, moong, soyabean; edible oil (soyabean, groundnut); dye (Indigofera);fibres (sunhemp); fodder (Sesbania, Trifolium), ornamentals (lupin, sweet pea); medicine (muliathi).
Solanaceae
It is a large family, commonly called as the ‘potato family’. It is widely distributed in tropics, subtropics and even temperate zones.
Vegetative Characters
Plants mostly herbs, shrubs and rarely small trees
Stem: herbaceous rarely woody, aerial; erect, cylindrical, branched, solid or hollow, hairy or glabrous, underground stem in potato (Solanum tuberosum)
Leaves: alternate, simple, rarely pinnately compound, exstipulate; venation reticulate
Floral Characters
Inflorescence : Solitary, axillary or cymose as in Solanum
Flower: bisexual, actinomorphic
Calyx: sepals five, united, persistent, valvate aestivation
Corolla: petals five, united; valvate aestivation
Androecium: stamens five, epipetalous
Gynoecium: bicarpellary obligately placed, syncarpous; ovary superior, bilocular, placenta swollen with many ovules, axile
Fruits: berry or capsule
Seeds: many, endospermous
Floral Formula: ⨁⚥K(5)C(5) ͡ A5G(2)
Economic Importance
Many plants belonging to this family are source of food (tomato, brinjal, potato), spice (chilli); medicine (belladonna, ashwagandha); fumigatory (tobacco); ornamentals (petunia).
Liliaceae
Commonly called the ‘Lily family’ is a characteristic representative of monocotyledonous plants. It is distributed world wide.
Vegetative characters:
Perennial herbs with underground bulbs/corms/rhizomes
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, epitepalous
Gynoecium: tricarpellary, syncarpous, ovary superior, trilocular with many ovules; axile placentation
Fruit: capsule, rarely berry
Seed: endospermous
Floral Formula: Br ⨁⚥P(3+3) ͡ A(3+3) G(3)
Economic Importance
Many plants belonging to this family are good ornamentals (tulip, Gloriosa), source of medicine (Aloe), vegetables (Asparagus), and colchicine (Colchicum autumnale).
