Fabaceae and Papilionaceae: Characters, Economic Importance, Distribution and Types

Diagnostic characters of Fabaceae:

1. Habit: Annual or perennial, Herbs, shrubs, vines, or trees.

2. Roots: Fibrous tap root often develops nodules in herbs. Nitrogen fixing bacteria live in these nodules.

3. Stem: Herbaceous or woody: Cylindrical, tendril climbers.

4. Leaves: Petiolate: alternate: compound of pinnate type, Stipulate, stipules maybe reshape / modified into leaves or thrones: parallel venation.

5. Inflorescence: Racemose or cymose, the flowers are clustered in heads.

6. Flower: Pedicillate; bracteate; actinomorphic or zygomorphic; regular, complete; hermaphrodite: pentamerous; hypogynous but slightly perigynous.

7. Calyx: 5 or sometimes 4 sepals: free or fused green.

8. Corolla: 5 sometimes 4 petals; free or united, colour.

9. Stamens: 10 or numerous stamens; polvandrous, in some causes diadelphous. anther

basifixed.

10. Carpel: Monocarpillary; ovary superior, placentation marginal.

11. Fruits: Legume or sometimes lometum.

12. Seed: Non-endospermic seed.

Sub-families (Families):

This family is divided into three sub-families. Now these sub-families are given the rank of families.

(a) Papilionaceae (Pea family):

This sub-family has about 400 genera and 9000 Species around the world. The members of this family occur globally, particularly warm and temperate regions/zones.

1. Habit: These are trees, shrubs and herbs.

2. Roots: It has tap roots. Roots bear nodule in which nitrogen fixing bacteria lives.

3. Stem: It may be herbaceous, woody or climber with tendrils. Tendrils are wiry, coiled and thread like formation/structure.

4. Leaves: They have a compound (rarely simple), alternate, and stipulate leaves. The stipules are often leafy. Sometimes, these leaves are partially or completely modified into tendrils form.

5. Inflorescence: It may be Racemose or solitary axillary.

6. Flowers: They have bisexual, zygomorphic, bracteate, pedicillate, perigynous,

pentamerous and papilionaceous flowers.

7. Calyx: They have 5 sepals. These petals are mostly united/joined to form a tube. These

are hairy (softly thorns).

8. Corolla: They have papilionaceous corolla. In this case, there are 5 clawed petals. These petals are not similar.

(a) Standard or Vexillum: It is the upper posterior petal. It is large and conspicuous.

(b) Wings: These are two lateral free petals.

(c) Keel or Carina: These are two anterior most petals. They fuse to form a bost-shaped structure.

9. Androecium: They have 10 mostly diadelphous stamens. The 9 stamens fused to form a sheath around the pistil. The 10th posterior stamen is free.

10. Gynoecium: It has a simple pistil. This pistil has a single carpel (monocarpellary) with a single locule. The ovary is superior. The style is long bent at its base. The placentation is marginal.

11. Fruit: Fruit is usually a legume or pod.

12. Seed: Seed is exalbuminous. It is usually flattened.

Floral formula of Papilionaceae:

K(5) C1+2+(2) A(9)+1 G1

Floral diagram of Papilionaceae:

Economic Importance of Papilionaceae:

1. Food: Most of the important pulses are belonged to family Papilionaceae. These pulses are used as food for living beings. Pulses are enrich source of proteins. The common species of pulses are Gram, Pea and Kidney bean etc.

2. Fodders: Medicago sativa (Alfalfa) belongs to the family Papilionaceae is one of the best forage crops. Vicia Melilotu and Trifolium are also cultivated as main fodder (edible for animals) crops.

3. Timber: Many plant of the family Papilionaceae provide timber for manufacturing of building, furniture and fuel. The main timber plants are Butea, Dalbergia etc.

4. Vegetable oil: The seed of Archis hypogea (generally known as peanut) are edible. They are also used for extraction of peanut oil. This peanut oil is hydrogenated and used as Vegetable oil.

5. Dyes: Some of its plants give yellow and indigo dyes.

6. Medicinal plants: Many plants of this family are used in medicines, Glycyrrhiza, glabra is used for cough and cold. Clitoria ternatea is use against snake bite.

7. Ornamental plants: Some important ornamental plants are Lathyrus (pea) Lupinus, Clitoria, Butea etc.

Common Species of Papilionaceae:

1. Lathyrus odoratus generally known as Sweet pea.

2. Arachis hypogea generally known as Peanut.

3. Cicer arietinum generally known as Chick pea.

4. Dalbergia sisso generally known as Shisham.