The paper presents research on the copper content in potato tubers and green matter of fodder sunflower grown in 1986-2001 on podzolic soil developed from loess (static fertilization field). The plant growing experiment was established in a randomized sub-block design on a static fertilization field in a four-year rotation system with mineral NPKMg and NPKMgCa nutrition. The rotation included potato, spring barley, fodder cabbage and winter wheat in 1986-1989, and potato, spring barley, fodder sunflower and winter wheat in 1990-2001. Mineral nutrition consisted of NPK fertilization with constant Mg and varied NPK fertilization with constant Mg and Ca nutrition (liming). Liming was carried out in 1985, 1989, 1993 and in 1997 (4 t ha-1 CaO). The copper content in plants was determined with the FAAS technique after digesting plant samples in a mixture of HNO3, HClO4, H2SO4 at a 20:5:1 ratio. A reduction in the copper level in green biomass of fodder sunflower was observed. Mineral fertilization resulted in an increase of the copper content in sunflower green matter. No interaction between liming and mineral nutrition in shaping the copper content in green biomass of fodder sunflower was recorded. The copper content in potato tubers did not depend on liming, mineral nutrition or on the interaction of these treatments. Some tendency towards decreasing the copper content in potato tubers due to liming and mineral fertilization was noticeable.

19.2.2014