Foliar application of growth regulators or fertilizers containing biostimulators can influence the uptake and accumulation of mineral elements by plants. The aim of the research was to determine the influence of foliar application of ‘Pentakeep V’ and diverse nitrogen fertilization on the content of: Ag, Al, Ba, Cd, Co, Cr, Ga, Li, Ni, Pb, Sb, Sr, Ti and V in spinach leaves. In 2006–2007 pot experiment with spinach Spinacia oleracea L. ‘Spinaker F₁’ cultivation on silty medium loam was carried out. The experiment design included two sub-blocks: with and without foliar nutrition. Plants with foliar nutrition were sprayed twice with 0.02% w/v ‘Pentakeep V’ fertilizer (3000 dm³ water per 1 ha). In each sub-block soil nitrogen fertilization (in the form of ammonium nitrate) was applied in following combinations: 1 – control (without N), 2 – 50% N dose prior to seed sowing (25 mg N∙dm^-3 of soil), 3 – 100% N dose prior to seed sowing (50 mg N∙dm^-3 of soil). Foliar application of ‘Pentakeep V’ resulted in (compared to not treated plants): a) significant reduction of the Ag, Al, Ba, Ga, Sr and Ti concentration in plants not fertilized with nitrogen, b) increase in Sr content in spinach fertilized with 100% of N dose, c) relatively weak tendency to lower V accumulation in control plants. The lowest concentration of cobalt was found in plants fertilized with 50% of N dose and not treated with ‘Pentakeep V’. No interaction between foliar nutrition and nitrogen fertilization was found in reference to Cd, Cr, Li, Ni, Pb and Sb content in spinach plants.

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