The aim of the field experiment was to analyze the impact of various nitrogen and sulphur doses on the content and uptake of spring grains of iron, manganese, copper, and zinc. The study was conducted in southeastern Poland (2009–2011) on Cambisols (WRB 2007), in conditions of low soil sulphur content. The experiment included 4 doses of N fertilization (0, 40, 80, and 120 kg/ha) and 2 doses of S application (0 and 50 kg/ha). The analysis showed that fertilization with nitrogen and sulphur had a positive effect on the studied features of spring wheat. The combination resulted in beneficial content of Fe, Mn, Zn, and Cu (Fe 45.00, Mn 35.67, Zn 34.63, and Cu 3.65 mg/kg) and beneficial uptake of microelements by grain DM (Fe 216.1, Mn 171.3, Zn 166.4, and Cu 17.52 g/ha). The highest grain yield (5.43 t/ha) was obtained after the application of nitrogen at a dose of 80 kg/ha and sulphur at a dose of 50 kg/ha. In relation to control, this increase of grain yield amounted to 13.3%. Significant correlations were also found between grain yield and the content and uptake of all microelements, as well as between elements. No significant correlation was found only between the content and uptake of Fe and the content of Mn and between the content of Mn and Cu. Sulphur supplementation of NPK fertilization can be a good means of agronomic biofortification for spring wheat in order to increase the content and uptake of micronutrients such as Fe, Mn, Zn, and Cu.

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The aim of the study was to evaluate the effect of nitrogen (N) and sulphur (S) fertilizers on the content and uptake of macronutrients by grain dry mass (DM) of spring wheat. A field experiment was conducted in southeastern Poland on Cambisols (WRB 2007), in conditions of low S content in the soil. The experiment included 2 factors: fertilization with N (0, 40, 80, 120 kg ha-1) and with S (0, 50 kg ha-1).The experiment showed a positive response of spring wheat to N and S fertilization. The highest grain yield was found after application of 80 kg N ha-1 and addition of 50 kg S ha-1 (5.43 t ha-1). The described combination resulted in beneficial content of phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca) (P –4.267, K–4.533, Mg–1.567, Ca–0.433 g kg-1) and uptake of macroelements by grain dry mass (DM) (P–20.48, K–21.79, Mg–7.52, Ca–2.08 kg ha-1). A generally positive correlation was found between content and uptake of macronutrients with exception of P content. Fertilization with N caused significantly narrowed mass ratios of K+: Ca2+, K+: Mg2+ and mass and mole ratio of K+:(Ca2++Mg2+) and increased mass ratio of Ca:P. While S application narrowed significantly, mass ratios of K+:Ca2+ and K+: (Ca2+ + Mg2+) and increased mass ratio of Ca:P.

In recent years, sustainable agriculture has revitalized interest in crop rotations and their effects on crop performance and agroecosystem biodiversity, including weeds. This article used winter rye as an example and focused on the crop rotation (CR) impact on species, taxonomic and functional diversity of weed communities and analysed the contribution of crop rotation to protecting yield and regulating weed abundance. Long-term continuous rye cropping (CC) provided a background for comparison. Two variants of plant protection were also adopted: herbicide application (H+) and no plant protection (H−). The data from the 10th, 30th and 50th years of the experiment were included in the analysis. Diversified crop rotation with no chemical protection resulted in a satisfactory rye yield and reduced weed abundance—especially problem species—without a decrease in weed species diversity or functional diversity. When rye was grown under crop rotation, the herbicide application had no effect on yield protection, but it was harmful to weed biodiversity. The rye yield correlated negatively with weed biomass, but did not show a link with weed biodiversity. Continuation of long-term experiments as a research basis for contemporary and future scientific challenges is necessary.

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