TAXONOMY: COMPOSITAE OR ASTERACEAE FAMILY

· The Compositae family is also known as the sunflower family.
· This is the largest family of angiosperm.
· There are about 1000 genera and 2300 species.
· They are cosmopolitan in distribution.

Some economically important members of the Compositae family are:
· Helianthus annuus, SUNFLOWER - Important for oil
· Chrysanthemum indicum, CHRYSANTHEMUM - Important ornamental flower
· Tagetes erecta, HAJARI PHOOL, Marigold - Important ornamental flower
· Artemesia indica, TITEPATI - Important medicine for skin disease and anti-helminthic
· Ageratum conyzoides, GANDHE - important medicine for cut and wound
· Carthamus tinctorius, KUSUM - important medicine

1. Habit/Habitat:
· Mostly they are annual herbs or perennial shrubs, some are climbers, wild or cultivated, ornamental, few are trees (Veronica arborea), hydrophytic, mesophytic or xerophytic.

2. Root: Taproot, branched or adventitious

3. Stem: Erect or prostrate, few are climbing, herbaceous or woody, solid or fistular, branched, cylindrical or angular, hairy or glabrous, sometimes underground or stem unbranched.

4. Leaf: Exstipulate or stipulate, petiolate, cauline and Ramal, alternate or opposite or whorled, simple or compound, pinnately compound, lanceolate, serrate or entire, acute, unicostate, reticulate venation, sometimes leaves are modified into spines or reduced.

5. Inflorescence:
· Head or capitulum,
· Head consists of two types of flowers Ray florets and disc florets,
· Head is surrounded by an involucre of bracts

6. Flowers:
A. Ray florets
· Bracteate, ebracteolate, sessile, zygomorphic, unisexual, incomplete, epigynous, ligulate
a. Calyx: Rudimentary, sometimes absent or hairy or scaly
b. Corolla: Petals – 3-5, gamopetalous, bilabiate, velvet aestivation.
c. Androecium: absent
d. Gynoecium:
· carpels – 2, bicarpellary, syncarpous,
· Ovary – inferior, unilocular, 
· Basal placentation,
· Style – Single,
· Stigma – bifid
e. Fruit: Cypsela
f. Seed: Non-endospermic, dicotyledonous


B. Disc Florets
· Bracteate, sessile, ebracteolate, actinomorphic, hermaphrodite, pentamerous, epigynous, sometimes unisexual.
a. Calyx: Reduced or absent or sometimes hair-like or scale-like – 2 - 5.
b. Corolla: Petals – 5, gamopetalous, tubular, bilobed, velvet aestivation.
c. Androecium: stamens – 5, polyandrous, syngenesis, epipetalous, Anther – dithecous, basifixed, introse.
d. Gynoecium: Carpels – 2, bicarpellary, syncarpous, Ovary – inferior unilocular, basal placentation, Style-long, Stigma-bifid.
e. Fruit: Cypsela
f. Seed: Dicotyledenous, Non-endospermic


Systemic position:
Class: Dicotyledonae
 Subclass: Gamopetalous
  Series: Inferae
   Order: Asterales
    Family: Compositae



Diagnostic characters of Compositae Family are:
· Leaves simple or compound, opposite or whorled.
· Inflorescence Head or capitulum.
· Flower - bracteate, epigynous, Two types-ray and disc florets.
· Sepals are rudimentary or hairy or scaly & 2-5 whereas Petals – 2-5, gamopetalous
· Stamens absent in ray florets but stamens – 5 in disc florets, polyandrous, syngenesious.
· Carpels – 2, bicarpellary, syncarpous.
· Ovary – inferior, unilocular, 
· Basal placentation, 
· Stigma-bifid


Common plants of the Compositae family are:
· Tagetes erecta – Marigold
· Tagetes patula – Marigold
· Helianthus annuus – Sunflower
· Calendula officianalis
· Eupatorium
· Chrysanthemum
· Artimesia vulgaris
· Dahlia
· Biden bidata

High Yielding Points from TAXONOMY

1. Shapes of corolla:
a. Cruciform: cross(x) like corolla eg. Cruciferae
b. Tubular: tube-like eg. sunflower
c. Papilionaceous: butterfly shape eg. legumes
d. Bilabiate: 2 lipped eg. libiatae
e. Personate (masked): bilabiate corolla with a narrow opening

2. Types of nomenclature:
a. Holotype: Specimen used by the author to confer scientific name to species
b. Isotype: Duplicate of holotype
c. Paratype: specimen cited with the original description other than holotype or isotype
d. Neotype: If the original specimen is lost it can be substituted by another specimen collected from the same locality
e. Lectotype: Specimen selected from the original material selected to serve as nomenclature type [@ HIPaNL]

3. Famous book ‘Species Plantarum’ 
was written by Carolus Linnaeus but ‘Genera Plantarum by Batham and Hooker

4. In the artificial system of classification, one or two characters are considered given by Carolus Linnaeus

5.
 In the natural system of classification, a large no. of traits are considered, given by Bantham and Hooker

6.
 Phylogenetic system of classification was given by A. Engler, Karl A. Prant and John Hutchinson.


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