The paper presents results of studies on the influence of liming and mineral fertilization on the yields and boron content of potato tubers and green matter of fodder sunflower grown in four and three rotations, respectively, on soil developed from loess. The experiment was set up on a field submitted to long-term fertilization and located in the village Krasne near Rzeszow, lying in the Rzeszów Foothills (Poland). Boron was determined colorimetrically with diantrimide after digestion of dried plant material at 550°C and dissolution of the residue in hydrochloric acid solution. Average yields of potato tubers and green matter of fodder sunflower were higher after liming, but statistical significance was confirmed only for fodder sunflower. Mineral NPK fertilization, regardless of liming, significantly enhanced the yield of green matter of fodder sunflower and, in most fertilization treatments, raised potato tuber yields. Potato tubers accumulated much smaller amounts of boron (2.2-7.5 mg kg-1 DM) than aerial parts of fodder sunflower (20-60 mg kg-1 DM). The boron content was significantly lower in potato tubers from the limed variant than in plants from the non-limed field. The response of sunflower to soil liming was opposite. The mineral fertilization applied, regardless of liming, had no significant effect on the boron content of potato tubers. Mineral nutrition reduced the boron content in the sunflower biomass under the influence of increasing doses of nitrogen and against the background of constant phosphorus-potassium fertilization.

22.2.2017