Characteristic features and economic importance of family Compositae or Asteraceae

  • This family is also known as Daisy family.
  • It includes the plants that are normally cultivated for ornamental flowers as well as for oil value.
  • They are annual garden herbs.

Roots:  They have tap root system and the roots are branched.


  • The stem is erect, branched and cylindrical.
  • It may be herbaceous or woody.
  • It is pubescent (covered with soft short hair) and green in color.


  • Simple leaves; entire and spathulate
  • They are cauline or ramal, alternate or exstipulate.
  • The leaves are sessile or petiolate, acute or serrate and with unicostate reticulate venation.


  • Racemose head or capitulum with three series of involucre of leafy bracts like in sunflower
  • Capitulum may be covered by green involucre consisting of single series of bracts.


  • 2 kinds of florets (central tubular disc florets surrounded by peripheral ray florets) in the large capitulum
  • Bracteate, regular, epigynous, sessile
  • May be bisexual or unisexual, actinomorphic or zygomorphic

Ray floret:

  • Bracteate or ebracteate, sessile
  • incomplete, unisexual, pistillate or neuter, ligulate
  • zygomorphic and epigynous, yellow to orange in color.


  • Sepals are normally absent.
  • If present, they are represented by 2 or 3 small scales or hairy pappus, superior


  • 3 to 5 teeth are present that represent the number of petals
  • Gamopetalous, ligulate with large flat strap-shaped limb and a basal hairy tube
  • Valvate, superior and yellow to orange in color

Androecium: Stamens are generally absent.


  • Bicarpellary syncarpous with inferior ovary
  • Ovary is unilocular with only one ovule with basal placentation.
  • Style is simple and slender whereas stigma is bifid and curved.

Disc floret:

  • Bracteate or ebracteate, sessile, actinomorphic
  • My be complete or incomplete, bisexual
  • Tubular, epigynous, actinomorphic
  • Small and yellow to orange in color


  • Absent or reduced and modified into 2 or 3 membranous white scales, superior


  • 5 teeth representing the number of petals
  • gamopetalous, tubular, valvate, superior
  • yellow to orange in color


  • 5 stamens are present, epipetalous, alternating with the petals, superior
  • filament is short and free
  • anther is large, dithecous with prolonged connective
  • syngenesious and introsse


  • bicarpellary syncarpous
  • ovary is inferior and unilocular with large ovule
  • basal placentation, style is simple whereas stigma is bifid

Fruit: Cypsela

Floral  diagram with floral formula (Helianthus annuus or sunflower):

Some important plants of the family:

  • Helianthus annuus (Sunflower)
  • Calendula officinalis (Englilsh marigold)
  • Tanacetum coccineum (The painted daisy)
  • Arctotis fastuosa (Monarch of the veld)
  • Townsendia jonesii (Townsend daisy)
  • Helianthus tuberosus (Jerusalem artichoke)
  • Carthamus tinctorius (safflower)
  • Chrysanthemum coccineum (pyrethrum)

Econonmic importance:

  • Helianthus annuus (sunflower) seeds yield edible oil.
  • Helianthus tuberosus (Jerusalem artichoke) root tubers are edible.
  • Carthamus tinctorius (safflower) petals yield an orange dye and the oil is used for the manufacture of soap, dye, varnish and is also edible.
  • Artemisia vulgaris (mugwort) and Artemisia maritima (sea wormwood) flowers yield santonine, a drug used for curing intestinal worms, asthma and brain disorders.
  • Chrysanthemum coccineum (pyrethrum) roots yield pyrethrum, an insecticide.
  • Enhydra fluctuans (water cress) leaves are used as vegetable and also to cure insomnia (sleeplessness).
  • Eclipta alba (false daisy) leaves are used as hair tonic.
  • Tagetes erecta (Mexican marigold) flowers are used for eye diseases, purification of blood and in ulcers.
  • Calendula spp.(marigold), Tagetes patula (the French marigold), Chrysanthemum spp. etc. have ornamental value (used as decorative plants).

Characteristic features and economic importance of family Compositae or Asteraceae