Plants are generally subjected to a combination of different conditions such as magnetic field and soil bacteria in their life. The present investigation tried to compare the effects and interactions of magnetic field and rhizobial inoculant in alfalfa. A pot experiment was performed under a natural condition by a factorial design to investigate the influences of magnetic field with 0.75 and 1.5 mT intensities on treated and untreated alfalfa seed with Sinorhizobium meliloti. Results showed that 1.5 mT magnetic intensity reduces growth parameters, protein content, catalase, ascorbate peroxidase, and peroxidase activity as a stress factor while superoxide dismutase activity, malondialdehyde, and reducing sugars content increased. Interaction of rhizobial inoculant and 1.5 mT intensity can reduce the damage caused by magnetic field generated in the plant. Application of 0.75 mT intensity and rhizobial inoculant (individual and together) led to a significant increase in growth parameters, protein content, catalase, ascorbate peroxidase, peroxidase, and superoxide dismutase enzyme activity while malondialdehyde and reducing sugars content reduced. Therefore, as an eco-friendly technique in agriculture, the application of 0.75 mT and rhizobial inoculant might improve the plant quality. This method could be used as a biofertilizer for vegetable production which reduces the environmental pollution caused by the application of biochemical fertilizers. پرونده مقاله