FABACEAE

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            1. SYSTEMATIC POSITION:
            Bentham & Hooker
            Division: Phanerogames (Seed Plants)
                  Class: Dicotyledones
                          Sub-class: Polypetalae
                                 Series: Thalamiflorae
                                       Order: Rosales
                                              Family: Fabaceae
           
            2. MORPHOLOGICAL CHARACTERS:
            Habit – Herbs, shrubs or trees, often climbing.
            Leaves – Compound, alternate.
            Inflorescence  – Racemose to cymose head or panicle.
            Flower – Hermaphrodite, actinomorphic or zygomorphic, slightly perigynous.
            Calyx – Sepals 4 or 5, free or united.
            Corolla – Petals 4 or 5, papilionaceous, aestivation vexillary or valvate or imbricate.
            Androecium – Stamens 10 or more, sometimes less, free or diadelphous.
            Gynoecium – Carpel one, ovary superior, unilocular, stigma capitates, style long, placentation marginal.
            Fruit – Legume or pod.
            Seed – Embryo large, cotyledon fleshy or leafy.
           
            3. FLORAL FORMULA: ⊕  or☿% Pα,K(4 or 5),C(4 or 5),A 10 or more,G1
            
            4. COMPARATIVE SYSTEMATIC POSITION AND AFFINITIES:
            Bentham & Hooker, Engler & Prantl and several others included the Fabaceae in the order Rosales. Bentham & Hooker and several other taxonomist divided the family Fabaceae into three sub-families like – Papilionaceae, Caesalpiniaceae and Mimosaceae. Hutchinson considered these three sub-families as a single family and placed in a single order Leguminales or Fabales.
            According to Hutchinson, of the three families, Cesalpiniaceae is the most primitive. According to him, it closest to Rosaceae and seems to have been derived from the rosaceous stock. He considered the fabales close to Sixifragales and derived from their immediate ancestors.
                5. ECONOMIC IMPORTANCE:
            1. Cicerarietinum (Gram), Lens culnaris (Lentil), Phaseolus aureus (Green gram), Pisum sativum (Pea), Arachis hypogaea (Ground nut), Cajanus cajan (Pigeon pea), Glycine max (Soyabean), Dolichos lablab (Broad bean) yields important food grains.
            2. Dalbergia sisso, Acacia melanoxylon, A. visco, Albizia lebbeck, A. procera, etc. yields valuable timber.
            3. Samanea saman (Rain tree) is planted as a shade tree on the road sides.
            4. Khair is obtained from the seeds of Acacia catechu.
            5. Cassia fistula (Gold mohur), Delonix regia (Indian laburnum) are planted as ornamental plants.

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