This paper presents results of a study on the nickel content in grain of winter wheat and spring barley grown on a constantly fertilized field lying on loessial soil and situated in Podgórze Rzeszowskie. The experiment was set up in randomized sub-blocks, by growing potato, spring barley, fodder sunflower and winter wheat plants in 4 four-year crop rotation cycles. Fodder cabbage was grown in the second crop rotation instead of sunflower. The first variable factor was liming (A2) or its lack (A1), while the second one consisted of different doses of mineral fertilization. Mineral NPK nutrition was applied against the background of constant Mg as well as Mg and Ca fertilization (liming). The general fertilization level (N1P1K1) for spring barley was: 80 kg N ha-1, 43.6 kg P ha-1 and 99.6 kg K ha-1, while for winter wheat it was: 90 kg N ha-1, 34.9 kg P ha-1 and 83 kg K ha-1. Constant magnesium fertilization was applied at a 24.1 kg Mg ha-1 dose. Liming at a dose of 4 t CaO ha-1 was applied before starting the experiment and each year that completed a subsequent crop rotation. The nickel content in crops was determined with the FAAS technique (Hitachi, Z 2000) after digesting samples in a mixture of HNO3:HClO4:H2SO4, at a 20:5:1 ratio. There was a significant decrease in the nickel concentration in grain of winter wheat and spring barley due to liming. Mineral nutrition had no impact on variation in the amounts of elements in grain of the two cereals. However, some tendency towards a lower metal content in winter wheat grain resulting from increasing NPK doses applied at a constant N:P:K ratio was recorded. Interaction of liming with mineral fertilization (NPK) caused a several-fold decrease in the nickel content in grain of winter wheat from the limed treatments, while on the remaining plots it had no statistical influence on the concentration of this element in grain of spring barley.

24.1.2019