The experiment was performed on sandy and silty soils different in physical and chemical characteristics. The forecrop on both soils was rye. Mineral fertilization comprised 3 doses of NPK (calculated in kg per ha): 1. 40 N, 13 P, 66 K; 2. 80 N, 26 P, 132 K; 3. 120 N, 39 P, 199 K (control object – without fertilization). Seeds were sown in October (2 kg ha–1) in rows 40 cm apart. Growth and development of plants depended upon both: soil conditions and fertilization. On silty soil plants were higher, developed more side branches and seed capsules. On
both soils fertilization promoted the growth and development of plants. On average, the yield of seeds on silty soil was twice as high on sandy one. Increasing fertilization, however, resulted in a higher seed yield only on sandy soil. Oil content in seeds was higher on silty soil (on average by 2.8%). Fertilization of this soil did not markedly affect oil content, while on sandy one it clearly decreased. The content of GLA in oil was slightly higher in seeds from sandy soil, increasing fertilization gave similar effect (on both soils).