Effects of fertiliser use and pre-sowing seed stimulation with a magnetic field on the mineral content and yield of three varieties of sugar beet roots

The study investigated the effects of using mineral fertilisers and pre-sowing stimulation of seeds on the yield of roots and the content of selected mineral elements in the roots of three sugar beet cultivars. The treatment consisted of applying a slowly changing magnetic field of 50 mT induction for a period of 60 seconds, so as to avoid heating the research material. The biological material was divided into four groups, taking into account the magnetic field and fertiliser applied. The first group was untreated seeds, the second one comprised seeds stimulated only with a magnetic field, the third one consisted of seeds pre-sowing stimulated with a magnetic field and then treated with mineral fertilisers and the last group was composed of seeds treated with mineral fertilisers. The assessment focused on the total yield of sugar beet roots as well as the content of eleven mineral elements, including three toxic metals analysed on an ICP-OES optical spectrometer. The application of mineral fertiliser resulted in a significant increase in the yield of sugar beet roots, and in a higher content of basic macroelements. On the other hand, stimulation with a magnetic field led to an increase in the yield of sugar beet roots which, although statistically higher than in the control group, was lower than after an application of mineral fertilisers. Additionally, the pre-sowing magnetic stimulation of sugar beet seeds resulted in a mild reduction in the transfer of elements from soil to plant, and a nearly complete blocking of such transfer in the case of harmful elements.