Effects of different variants of basalt-sulphur improver in the fertilisation of spring oilseed rape

The aim of the research was to test of several variants of basalt-sulphur improver, differing in the ratio of the two components, and to select the most suitable one for oilseed rape. Basalt dust, which is a troublesome by-product of rock processing, and elemental sulphur were used to produce the improver. The study included 3 improver variants with 1, 1.5 and 2% S and a control treatment without an improver. The experiment was conducted in concreted microplots filled with two soils: sandy loam and loamy sand, in a split-block two-factor design, in 4 replicates. The most suitable variant for rapeseed was the variant containing 1.5% S, which resulted in a 12% increase in rape-seed yield on sandy loam. Moreover, for this variant, an increase in seed fat content, an increase in the bioavailable form of sulphur in the soil and an increase in the concentration of this nutrient in oilseed rape straw and seed were observed on both soils.