Asteraceae

Family: Asteraceae (Compositae)
Lecture of: Sir Muhammad Ajaib
Department of Botany
G C University Lahore
Provided by: Taha Arooj

This Family is known as sunflower or daisy Family. It is the largest Family of Angiosperms. It includes about 1535 genera and 23,000 species distributed in 3 sub families and 17 tribes. It has a cosmopolitan distribution. There are around 650 species distributed in 15 tribes in Pakistan.
Vegetative Characters:
Habit: Mostly annual, biennial or perennial herbs, sometimes shrubs and rarely trees.
Root: Taproot, branched.
Stem: Herbaceous or woody, erect, branched.
Leaves: Simple, Alternate and opposite, exstipulate, petiolate, hairy, reticulate venations, toothed, lobed or variously dissected.
Inflorescence: Head or capitulum, terminal or axillary. Florets surrounded by involucre of bracts also called phyllaries.
Flower: Bisexual, pentamarous, heterochlaymadeous, epigynous.
Ray florets: Towards periphery, sessile, bracteate, pistillate or neutral, zygomorphic, ligulate.
Calyx: absent or hairy pappus, or scaly persistent.
Corolla: Petals 5, Gamopetalous, ligulate.
Androecium: Absent.
Gynoecium: Bicarpillary, syncarpous, unilocular, one ovule, basal placentation, style narrow, stigma branched, ovary inferior.
Disc Florets: Towards the center, bracteate, bisexual, actinomorphic, tubular, epigynous.
Calyx: Absent or modified to pappus.
Corolla: petals 5, gamopetalous, tubular.
Androecium: stamens 2, epipetalous.
Gynoecium: Bicarpillary, syncarpous, unilocular, one ovule, on basal placentation, style single, stigma bifid.
Neutral Florets: Both Androecium and gynoecium are absent. Remaining characters are similar.
Fruit: Cypsela.
Seed: Non-endospermic.
Common Examples:
Edible
  1. Lactuca sativa L. (Lettuce, Salad)
  2. Helianthus tuberosus L. tubers edible, seeds yield oil
  3. Helianthus annus L. yield oil which is used for cooking
Medicinal
  1. Carthamus tinctorius L. commonly called American Zafran. Oil used for treating injuries.
  2. Artemisia absinthium L. called chaho, yields santonin used for treating intestinal worms.
  3. Xanthium stramonium L. commonly called Bahangra booti. Leaves are used for treating tooth ache and fever.
Ornamental
  1. Helianthus annus L. Sunflower yields oil.
  2. Tagetes erecta L. Marigold.
  3. Dendranthema indicum (L.) Des Moul. (Chrysanthemum indicum L.) Gul-e-daudi.
  4. Vernonia elaeagnifolia DC. Sehra bel, Curtain creepers.

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