1. Family Asteraceae
• The family contains about 950 genera and
probably 20000 species.
• Distribution:
• Cosmopolitan in distribution.
• Vegetative characters:
• Habit: Herbs, shrubs, very rarely climbers (e.g.
Mikania scandens) and trees (e.g. Lachanodes
arborea). Many plants possess milky juice
while in others the juice is watery and bitter.
4. • Root: Tap root; branched. In some cases
tuberously thickened e.g. H. tuberosus
• Stem: soft, some times woody; usually hairy;
erect.
• Leaf: simple or compound; Alternate, sometime
opposite and rarely whorled, exstipulate;
petiolate, some time scales leaves.
• Floral characters:
• Inflorescence: Racemose: head or capitulum
• Flower: flowers of the capitulum, i.e. florets may
be hermaphrodite, unisexual or neutor;
pentamerous; actinomorphic or zygomorphic,
epigynous.
18. • Economic Importance of Asteraceae:
• 1. Food:
• Leaves of Lactuca sativa are used as salad. The
roots of Helianthus tuberosus are edible.
• 2. Oil:
• The seeds of Helianthus and Artemisia yield oil.
• 4. Rubber:
• It is obtained from Solidago laevenworthii and
Taraxacum.
• 5. Insecticide:
• The capitula of Chrysanthemum roseum and C.
cinerriefolium are dried, powdered and used as
insecticide.
19. • Medicinal:
• Solidago used in dropsy.
• Artemisia yields santonin which is used as
vermifuge.
• The roots of Taraxacum used in bowel disorders.
• The juice of Emillia sonchifolia leaves has cooling
effect and is used in eye inflammation and also
for night blindness.
• Eclipta alba used as tonic in spleen enlargement.
• Centipeda orbicularis is used in cold and
toothache.
20. • Ornamental:
• Zinnia, Dahila, Cosmos, Chrysanthemum,
Calendula, Helichrysium, Aster, Helianthus etc.
are well known garden plants.
• 7. Weeds:
• Xanthium, Blumea, Sonchus, Vernonia are the
common weeds.