Tap Root System
The tap root system consists of a single main root called the primary root which gives out lateral branches. The main root grows vertically downwards and is longer than it branches. This kind of root is found in carrot, mustard, gram, radish, beans and pea. Dig out a mustard plant from the soil and study it.
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Fibrous Root System
A number of thread-like roots arising from the base of the stem are called fibrous roots. They spread out nit he soil to provide firm support to the plant. This kind of root system if found in grasses, wheat, rice, maize and barley. Dig out a wheat plant from the soil and study it.