Briefly explain the mutagens commonly used in mutation breeding.

Mutagens are mutation causing agents . Mutagens are of the following two types: (a) chemical and (b) physical mutagens. Chemical mutagens are a variety of chemicals like ethylmethane sulphonate (EMS ) and sodium azide that induce mutations. Similarly, physical mutagens are several kinds of radiation, e.g., X-rays, gamma-rays, ultraviolet rays etc , that cause mutation. These agents induce changes in DNA and chromosomes, which leads to the development of new characters in plants. The plants with desirable qualities are then selected and  developed.