Plant Description

1. Family- Apocynaceae
(Dog Bane Family)
Dr. Shriram Kunjam
Assistant Professor
Department of Botany
Govt. V.Y.T. PG Autonomous College, Durg (Chhattisgarh)
B.Sc. Part-II, Paper-I Unit-02

2. Systematic Position
• Division- Angiosperm
• Class- Dicotyledons
• Subclass- Gamopetaly
• Series – Bicarpellatae
• Order (Cohort)- Gentianales
• Family- Apocynaceae

3. Distribution
• Tropical and subtropical areas of the world.
• About 415 Genera & 4600 species
• Most of plants are mesophytes and some are xerophytes
• All members of this family are poisonous,
• Many species are used medicinally because of the
presence of cardiac glycosides and various alkaloids.

4. Major genera and species
• Catharanthus roseus (Vinca rosea)
• Nerium indicum (Oleander)
• Thevetia nerifolia (Pili kaner)
• Alstonia scholaris (Chhatim)
• Plumeria champaca (Champa)
• Tabernemontana (Mongra)
• Rouwolfia serpentina (Sapagandha)

5. VEGETATIVE CHARACTERS
Habit:
• Perennial Herbs – Catharanthus roseus
• Twining shrub - Vallaris solanacea
• Shrubs or Small Tree - Nerium indicum,
Thevetia nerifolia
• Climbing shrubs - Landolphia and
Clitandra
• Small sized Tree - Alstonia scholaris &
Plumeria acutifolia
• Tuber like stem e.g. Adenium

6. VEGETATIVE CHARACTERS
• Stem:
• Herbaceous
(Catharanthus)
• Green
• Erect, cylindrical
• Branched
• Woody
• Solid
• Succulent with milky latex.
Branched
Stem
Milky latex

7. VEGETATIVE CHARACTERS
Leaves
• Simple
• Opposite (Catharanthus)
• Whorled (Nerium, Alstonia,
Thevetia)
• Petiolate or sub-sessile
• Exstipulate
• Margin entire
• Unicostate reticulate
venation
Opposite Phyllotaxy
Whorled
Phyllotaxy

8. FLORAL CHARACTERS
Inflorescence
• Usually Cymose type
• Solitary - Catharanthus
• Terminal cymes - Plumeria
• Corymbose Cymes - Carissa
• Umbellate cyme (Rauwolfia)
• Umbellate branched penicled
cymes (Alstonia)
Plumeria
Carissa
Rauwolfia Catharanthus

9. FLORAL CHARACTERS
Flower
• Bracteate or ebracteate
• Bracteolate
• Pedicellate
• Complete
• Hermaphrodite
• Actinomorphic
• Tetra or pentamerous
often with corona
• Hypogynous
Radial symmetry
Hypogynous
condition

10. FLORAL CHARACTERS
Calyx:
• Sepals 5,
• Gamo/polysepalous
• Deeply lobed
• Imbricate / valvate
aestivation
• Small often glandular
at the base
Sepals

11. FLORAL CHARACTERS
Corolla:
• Petals 5,
• Gamopetalous
• United into a tube, Tubular
or funnel shaped;
• Twisted or rarely valvate,
• contain some corona like out
growths at the mouth of the
corolla tube.
Corona or hairy
outgrowth
Petals

12. Types of Corolla
Funnel or Bell shaped Corolla
Ex. Allamanda, Thevetia
Tubular Corolla
Ex. Vinca rosea

13. FLORAL CHARACTERS
Androecium: (Male Reproductive organs)
• Stamens 5
• Polyandrous
• Epipetalous, alternating with
petals
• Filament - short, free
• Anthers - dithecous, connate to
stigma, Introse, basifixed
• Dehiscing longitudinally

14. FLORAL CHARACTERS
Gynoecium (Female reproductive organs)
• Bicarpellary, Syncarpous
• Ovaries are free below but united
by style only
• Superior ovary
• Style short, enclosed in a tube
formed by the corolla;
• Stigma (Dumble or Drum shaped)
• Ovary is unilocular,
• Marginal placentations

15. Floral Formula
• Vinca rosea:
• Tabernaemontana divaricata:
• Nerium indicum:
• Thevetia nerifolia

16. Floral Diagram
Source: Textbook of Practical
Botany by Bendre & Kumar

17. FRUIT
• A drupe (Thevetia)
• Berry (Carissa)
• Follicle (Nerium and Amsonia)
• Pollination
• Entomophilies

18. ECONOMIC IMPORTANCE
Vegetables
• The pulpy fruits of Carissa carandus are edible and also
pickled.
Medicinal
• Rauwolfia serpentina- Alkaloids – Serpentine in root
• Root are used in lowering blood pressure, sedative,
stimulator for uterine contraction and in mental
diseases.
• The juice of leaves is used for removal of opacities of
the cornea of the eyes.
• Anti-cancerous drugs are extracted from Catharanthus
roseus (Catharanthine and Vindoline alkaloids)

19. Rubber
• Many species of Hancora, Dyera, Urceola are the
sources of rubber.
Poisonous
• The seeds of Thevetia contain Thevetine a
poisonous glycoside.
• The latex of Acokanthera is used for poisoning
arrows.
• The bark and wood of Nerium indicum provide
rat-poison.
ECONOMIC IMPORTANCE