FIXATION OF MOLECULAR NITROGEN AND YIELD OF SOYA INOCULATED BY NODULEBACTERIA AND RHIZOSPHERE PSEUDOMONADES

The increase in the weight of grains and aboveground parts of soya was observed in a microfield experiment on gray forest soil under combine d inoculation by nodule bacteria Bradyrhizobium japonicum 110 with rhi zosphere bacterium Pseudomonas fluorescens 20 or P. fluorescens 21, an d endomycorrhiza fungus G. mosseae. It was accompanied by an increase in the amounts of ''biological'' nitrogen, soil nitrogen, and ''starti ng'' mineral nitrogen in the yield. Significant accumulation of nitrog en in the soil was due to the nitrogen concentration in humic substanc es after growing soya inoculated by mixed bacterial cultures. Rhizosph ere pseudomonades improve nodulation and intensify symbiotic fixation of nitrogen. The efficiency of a mixed culture of B. japonicum 110 and P. fluorescens 21 and the accumulation of nitrogen in the substrate ( soil + sand) in the greenhouse experiment depended on the level of pho sphorus nutrition. Maximum gain in the green mass and accumulation of nitrogen in the substrate were observed in conditions of high phosphor us supply.