The examples of crop improvement by mutation breeding include:

Artificially induced mutations resulted in increase in yield, reduction in height, insensitivity to day length and resistance to mildew disease in many varieties of barley

Mutations in red grained Sonara 64 and Lerma Rojo 64A varieties of wheat resulted Sharbati Sonora and Pusa Lerma respectively

X-ray treatment induced semi-dwarfing in rice plants