Tap Root System

The first root to emerge from a germinated seed is the radicle. This radicle, in most dicotyledons, enlarges to form a prominent taproot.
Taproots can serve many functions. In the sugar beet and carrot, the taproot stores large reserves of food (starch). In poison ivy taproots are modified to be very long and are for reaching water deep in the ground (Moore et al., 1995).

Fibrous Root System

However in monocots, such as the rice plant, the radicle is short-lived and replaced by a mass of adventitious roots (Moore et al., 1995). This mass of similarly sized roots are called a fibrous root system.

This picture shows the fibrous root system of the rice plant.

These roots are extensive and cling to the soil particles and thus are excellent for preventing erosion.

Adventitious Roots

Adventitious roots are roots which form from organs of the plant other than roots. The stem of the rice plant is the initiation site of the adventitious roots in the above picture. They form most of the monocots root system.

The root mass of a rice plant showing adventitious roots.

Introduction | Flowers&Fruit | Roots | Stems | Leaves

© Thomas L. Rost 1997
Section of Plant Biology Division of Biological Sciences