Response of soybean (Glycine max (L.) Merr.) to bacterial soil inoculants and foliar fertilization

Soybean yields can be considerably improved by inoculation with selected Bradyrhizobium japonicum strains and foliar fertilization. An exact field experiment was carried out in 2012-2014 at the Experimental Station of Cultivar Assessment in Przeclaw, Poland. The test plant was soybean cv. Aldana. The experimental factors were: bacterial inoculant Nitragina (Bradyrhizobium japonicum); foliar fertilization with Mikrokomplex; combined applications Nitragina + Mikrokomplex and the control treatment. Significant effect of Nitragina on an increase in the number of plants prior to harvest, plant height and the number of pods per plant was indicated. Fertilization with Mikrokomplex caused an increase in the number of pods per plant and thousand seed weight. Nitragina + Mikrokomplex increased the number of plants prior to harvest, plant height, the number of pods per plant and thousand seed weight. Seed yield was significantly higher in all the treatments compared to the control (2.31 t/ha). Higher soil plant analysis development values were found after the application of Nitragina + Mikrokomplex, and in the stage of pod development, also after foliar fertilization with Mikrokomplex. Application of Nitragina and Nitragina + Mikrokomplex resulted in an increase in leaf area index and mean tip angle and total protein in seeds. Fe content in seeds was the lowest in the control (69.2 mg/kg) and significantly higher in the other treatments (Nitragina, Nitragina + Mikrokomplex), and Mg content significantly increased after the application of Mikrokomplex and Nitragina + Mikrokomplex.