BOTANY Higher Secondary Second Year - Textbooks Online

1.3.3. RUBIACEAE – the coffee family
Systematic position
Class: Dicotyledonae
Sub-class: Gamopetalae
Series: Inferae
Order: Rubiales
Family: Rubiaceae
General characters
Distribution
Rubiaceae is one of the largest families consisting of nearly 500 genera
and more than 6,500 species. They are widely distributed in the tropical
and sub-tropical regions. In India, this family is represented by 76 genera
and more than 274 species.
Habit
Mostly trees (eg. Cinchona officinalis, Morinda tinctoria) or shrubs
(eg. Mussaenda) or herbs (eg. Rubia).
Root
A branched tap root system.
Stem
Aerial, erect, cylindrical, woody and branched but herbaceous in
Rubia.
Leaf
Simple, opposite decussate (eg. Ixora coccinea) or whorled (eg.
Galium), entire and stipulate. The stipules of opposite leaves are fused at
the node between the petioles. They are called interpetiolar stipules (eg.
Ixora coccinea). When the stipules of each leaf are fused at the angle
between petiole and stem, they are called intrapetiolar stipules. (eg.
Gardenia).
Inflorescence
Mostly terminal or axillary cymose (eg. Gardenia) or corymbose
cyme (eg. Ixora coccinea) or cymes are aggregated into dense head as in
Anthocephalus indicus (Kadamba tree).
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