Physiological and molecular characterization of the enhanced salt tolerance induced by low-dose gamma irradiation in Arabidopsis seedlings.

•50-Gy gamma irradiation markedly promotes the seedling growth under salt stress in Arabidopsis.•The contents of H2O2 and MDA are obviously reduced by low-dose gamma irradiation under salt stress.•Low-dose gamma irradiation stimulates the activities of antioxidant enzymes under salt stress.•Proline accumulation is required for the low-gamma-ray-induced salt tolerance.•Low gamma rays differentially regulate the expression of genes related to salt stress.