Tuesday, 23 September 2008
FAMILY OF THE WEEK : MELIACEAE
The Mahogany family contains 50 genera and 1400 species distributed exclusively in the tropical regions of the world. In India there are 19 genera and 72 species occurring mostly in the peninsular India.
They are mostly trees and shrubs, often with hard and scented wood.
The leaves are alternate, exstipulate and usually pinnate or rarely 3-pinnate(Melia azadirachta) or simple(Turraea). The leaflets are opposite or alternate., usually entire and more or less oblique at the base.
Inflorescence and flowers :
The inflorescence is usually an axillary cymose panicle.
The flowers are actinomorphic, hermaphrodite and hypogynous.
The calyx is composed of 3-6 sepals which are united or rarely free.
The corolla is also composed of 3-6 petals which are free or rarely connate at the base.
The androecium has four to 12 stamens which are inserted outside the base of the hypogynous disc. The filaments are mostly connate in a tube(monadelphous) but they are sometimes free as in Cedrela and Chloroxylon. The anthers are sessile on the staminal tube, included or axserted, dithecous, introrse and dehiscing longitudinally. A nectariferous disc is often present between the stamens and the ovary. The gynoecium is two to five carpellary and syncarpous with a superior two to five locular ovary. The style is short or absent and the stigma is discoid or capitate.
Fruits and seeds :
The fruit is loculicidal or septicidal capsule or sometimes baccate or drupaceous.
Pollination is usually by insects which visit them for nectar.
The winged seeds of toona are dispersed by wind. In others the dispersal may be by bats and birds or by squirrels.
Swietenia mahogani (West Indies Mahogany)
Khaya senegalensis (African Mahogany)
Toona ciliata Chickrassia tabularis (Chittagong wood)
Chloroxylon swietenia(Satin wood)
Melia azedarach(Bankayan)Bakana nimb
Melia dubia(कडू खजूर; निम्बारा )
Aphanamixis polystachya syn. Aphanamixis rohituka syn.Amoora rohituka
Posted by SATISFIED at 19:20