Fabaceae (Papilionaceae) – Lathyrus odoratus

Fabaceae (Papilionaceae)

The members of the family are distributed in plains and hilly areas of temperate regions of both northern and southern hemisphere. Most of the plants are herbs and flowers during winter. Most members are cultivated for their economic value as they are the source of pulses, fodder, etc. The family comprises of 375 genera

Distinguish Features:

• Herb, shrubs or tree
• alternate leaves
• compound leaflets are modified into tendrils,
• stipulated
• flower hermaphrodite
• zygomorphic
• perigynous
• calyx 5 united
• Corolla has a papilionaceous shape
• stamen ten in number diadelphous
• The ovary is with single carpal
• The fruit is a pod.
• The representative species is Lathyrus odoratus (sweet pea)

Lathyrus odoratus (sweet pea):

Lathyrusodoratus (Sweet pea) Flower & Leafs

Habit:

• Climbing herb
• cultivated as an ornamental plant

Root:

• Taproot
• Branched
• Root nodulated

Stem:

• Herbaceous
• weak
• Hollow
• Branched
• Winged
• Climbing

Leaf:

• Ramal and cauline
• Petiolate
• Petiole
• Winged
• Stipulate
• Stipules
• Foliaceous
• Imparipinnate compound
• Upper leaflet modified into a tendril

Leaflets:

• Sessile
• Opposite
• Reticulate unicostate
• Oval
• Entire, acute.

Inflorescence:

Solitary axillary or pedunculate raceme.

Flower:

• Bracteate
• Pedicellate
• Complete
• Bisexual
• Irregular
• Zygomorphic
• Slightly perigynous

Sweet Pea (Lathyrus odoratus) Flower

Calyx:

• 5 sepals
• Gamosepalous
• Campanulate
• Green
• Hairy
• Inferior

Corolla:

• 5 petals
• polypetalous
• Papilionaceous: a large posterior standard or vexillum
• Two small lateral ones forming wings of alae
• Two anterior ones united to form keel or carina
• imbricate
• inferior

Androecium:

• Ten stamens
• diadelphous: nine stamens united to form a tube around the ovary
• 10th posterior stamens free
• Anthers basifixed
• Introse
• Enclose in the keel

Gynoecium:

• Monocarpellary
• Ovary unilocular with numerous ovules and superior
• Placentation marginal
• Ovule numerous
• Style slightly hairy and bent towards the posterior side of the flower
• Stigma terminal.

Floral Formula: K (5) C1+2+(2) A (9)+1 G_1

Read Also :- Acacia nilotica