Sodium nitroprusside (SNP) is an important signaling molecule with diverse physiological functions in plants. In the present  study, grains of maize (strain G₄) which were irradiated with gamma irradiation doses (15 and 30 Gy) or sprayed  with sodium nitroprusside (150 and 300µM) induced significant enhancement on growth, photosynthetic pigments, and the content of Fe, Zn , Mg , Ca and Cu. The most enhancement effect was observed with spraying treatment (300µM SNP) or (15 Gy) gamma radiation dose. Antioxidant enzymes peroxidase, malate dehydrogenase, and Polyphenyl oxidase (PPO) isoenzymes electrophoresis showed appearance and disappearance of some bands with variation in density.