Abstract
The results of experiments with various terms and seed spacing and with differentiation of the supply of nitrogen fertilizer carried out in 1977 - 1979, are presented. Soybean was grown on two soil complexes with soil inoculation with Rhizobium japonicum bacteria. It appeared, that the most profitable seeding time of the medium-early phylum and cultivars of soybean falls is the turn between April and May and optimum seed spacing is 80 seeds por 1 m2 when row spacing is 25 cm. Nitrogen fertilizer influences the yield of seeds, but prolongs the soybean vegetation period one day per 10 kg N/ha. Fertilization above 60 kg N/ha causes soybean to ripen unequally and its technical value deteriorates. The effectiveness of nitrogen fertilizer is higher on the sandy soil of the good rye complex than on soil of the very good wheat complex. The favourable influence of soil inoculation with Rhizobium japonicum bacteria on the yield of soybean significantly increases with their activity.