Effect of Liming and Mineral Fertilization on the Nickel Content in Potato Tubers (Solanum tuberosum L.) and Green Biomass of Fodder Sunflower (Helianthus annuus L.) Cultivated on Loessial Soil

Abstract

The publication presents the results of the research on the nickel content in potato tubers and green mass of fodder sunflower grown on a constant fertilization field on lessive soil developed from the loess located at the Rzeszów Foothills. The experiment established by randomized block design used a four-year crop rotation, which included potatoes, spring barley, fodder sunflower, and winter wheat. Mineral NPK fertilization was used on a background of constant Mg as well as Ca and Mg fertilization (liming). The nickel content in crops was determined by means of FAAS technique (Hitachi, Z 2000) after samples digestion in a mixture of HNO 3 :HClO 4 :H 2 SO 4 at 20:5:1 ratio. A decrease of the nickel concentration in potato tubers and in green matter of fodder sunflower due to liming was observed. Mineral nutrition (regardless of liming) did not considerably affect the element content in potato tubers, yet it was significant for the metal content in green mass of sunflower. It was shown that the interaction of liming treatment with mineral fertilization contributed to the lowering of nickel concentration in test crops, especially in the green matter of the fodder sunflower (most of limed fertilization objects), while in potato tubers-to a lesser extent.