EFFICIENCY OF GREEN MANURE NITROGEN AT THE APPLICATION OF RYZOAGRIN FOR SPRING WHEAT (<i>TRITICUM AESTIVUM</i> L.)
The investigations of the effect of biopreparation ryzoagrin on the yield and grain quality of spring wheat on soddy-podzolic light loamy soil are presented. Inoculation of seeds by biopreparation provided the increase of grain yield by 20 %. Using the method of isotope display with the stable nitrogen isotope <sup>15</sup>N enabled to establish that the fraction of nitrogen fixed by rhizosphere diazotrophs in the yield formation was 20% on the background of PK, the utilization ratio of nitrogen from organic fertilizers amounted 38%. At the sealing of green manure into the soil and seed inoculation with ryzoagrin the ratio of nitrogen utilization by plants from green manure biomass reached 39%. Seed inoculation with biopreparation increased the removal of nitrogen with the yield by 25% on the potassium-phosphorus background and by 17% in the variant with green manure. In the experiment on soddy-podzolic soil with a low content of organic matter 56% of the green manure nitrogen was immobilized.