Influence of the mineral fertilizers on the formation of symbiotic apparatus and air nitrogen consumption by soybean under conditions of a central zone of the non-chernozem region of the Russian Federation

The different doses of nitrogen fertilizers (N30, N60 and N90 kg per ha) were studied. The research showed that the nitrogen fertilizers increase the accumulation of nitrogen by soybean sowings, but they suppress the formation of symbiotic apparatus and decrease air nitrogen consumption the stronger the higher their dose is. The fractional introduction of nitrogen fertilizers does not have an advantage over the single before-sowing introduction of an entire dose. The share of air nitrogen in total accumulation in a variant with application K60VMo was 63.3%, in variants with the nitrogen fertilizers it was lowered: at a dose N60 kg per ha - up to 45.0%, at a dose N90 kg per ha - up to 38.8%.