Modifications of Roots and Their Significance | Plant Morphology

In this article, we will discuss about:- What is Modified Roots? Modified tap root for storage, Tap root modified for respiration and Modification of adventitious roots

What is Modified Roots?

Tap and adventitious roots are modified in different forms to perform special functions are

called as modified roots.

1 . Modified tap root for storage :

(i) Fusiform Roots: These root are thicker in the middle and tapering on both ends. In this type of roots root help in storage of food. Eg . :- Radish

(ii) Conical roots: These roots are thicker at their upper side and tapering at basal end eg. Carrot

(iii) Napiform: These roots become swollen and spherical at upper end and tapering like a

thread at their lower end. Eg. Turnip (Brassica rapa ), Sugarbeet (Beta vulgaris )

(iv) Tuberous root: Such roots do not have regular shape and get swollen & fleshy at any

portion of roots. Eg. Mirabilis.

(v) Nodulated root: Nodules are formed on branches of roots by nitrogen fixing bacteria. (Rhizobium ) 

2 . Tap root modified for respiration:

The plants which grow in marshy areas, scarcity of oxygen is found. The plants, which grow in this region some branches of tap root grow vertically upward and comes on surface of soil. These roots are called pneumatophores have minute pores called pneumathodes or lenticels by which air entered the plant and get oxygen for respiration. Eg. Rhizophora, Mangrove, Heritiera

3. Modification of adventitious roots:

(i) Tuberous adventitious root : When food is stored in these roots, they become swollen and form a bunch. Eg. Sweet potato (Ipomoea batatus)

(ii) Fasciculated roots: These are adventitious roots occurring in clusters and all of them are Swollen. (These roots have no definite shape ) Eg . Asparagus , Dahlia

(iii) Fibrous: Roots are very thin and filamentous. Eg. Grass, Wheat

(iv) Nodulose: In this type, tip s of roots swell up. Eg. Melilotus , Curcuma

(v) moniliform:  When root swell supl ike a bead at different places after a regular interval. Eg. Vitis , Momord ica (Bitter gourd), Portulaca

(vi) Stilt roots or brace roots: When root arises from lower nodes and enter in side the soil and form a rope like structure, known as stilt roots Eg. Maize , Sugarcane, Pandanus ( screw pine)

(vii) Prop root or pillar roots: When root arises from branches of plant and grows downward towards soil function as supporting stem for the plant. This type of roots are called prop root Eg. Banyan

(viii) Butress root: Such roots appear from the basal part of stem and spread in different directions in the soil. Eg. Terminalia

(ix) Climbing roots: These roots arise from nodes and helps the plant in climbing Eg. Money plant (pothos ), Monstera, Betel (Piper betel), Black pepper

(x) Respiratory root: When the quantity of oxygen is low in soil then some root comes out from the soil and helps in respiration. Eg.Avicennia, Jussiaea

(xi) Foliar root or Epiphyllous root: When roots arise from leaf are called as foliar roots Eg. Bryophyllum, Begonia

(xii) Sucking or haustorial roots or Parasitic roots : – In parasitic plants, roots enter in the stem of host plant to absorbed nutrition from host. Eg . Dendrophthoe , Cuscuta, Viscum.

(xiii) Annulated roots : If the swelling is in a series of ring on the roots. Eg. Ipecac