Great development in medicinal, spice, and aromatic plant crops has occurred in Mediterranean countries due to their high added value as a consequence of the reappearance of phitotherapy, among other reasons. The main objective of this study is to determine the effects of magnetic treatment, in addition to the geomagnetic field, on germination of Salvia officinalis L. and Calendula officinalis L. seeds. This objective has a practical application in agricultural science: to obtain the early growth of both plants. Groups of 100 seeds were exposed to a 125 mT stationary magnetic field generated by magnets at different times, whereas the other group of 100 seeds was subjected to a magnetic pre-treatment, and non-exposed seeds were used as control. Germination tests were performed under laboratory conditions. The selected germination parameters were: time for the first seed to germinate (T₁), time to reach 10-75% germination (T₁₀, T₂₅, T₅₀, and T₇₅), mean germination time (MGT), and number of germinated seeds (G_max), all provided by the Seed calculator software package.
The germination parameters recorded for Salvia officinalis L. seeds for each treatment and pre-treatment were lower than corresponding control value. Among the various treatments, chronic exposure to 125 mT provided best results; the MGT was significantly reduced compared to control, parameters (T₁-T₅₀) were also significantly reduced for most treatments. Results obtained for Calendula officinalis L. seeds showed that germination parameters were reduced, in most cases, for magnetic treatment versus control, and all parameters of germination were reduced for pre-treatment versus control. The best results were obtained from chronic exposure. Results indicated that magnetic field application enhanced germination rate and percentage of germinated seed on the treated group compared to the non-exposed in both cases.