Brazilian Semiarid Bradyrhizobium Strains Increase Nitrogen Accumulation and Modulate Physiological Parameters to Enable Superior Grain Production in Soybean Genotypes

The selection of rhizobia for soybean is a sustainable strategy to increase the yield of this crop. The aim of this study was to investigate the efficiency of Bradyrhizobium strains for nitrogen fixation and modulation of physiological parameters and grain production in inoculated soybean genotypes. The experiment was carried out with three soybean genotypes (M8349 IPRO, M8372 IPRO, and Bônus 8579 RSF) and six nitrogen (N) sources (UFLA06-19, UFLA06-22, UFLA06-24, a commercial inoculant, and two controls without inoculation (without and with nitrogen)). The UFLA strains increased nitrogen accumulation in the shoots of the M8372 IPRO genotype and modulated photosynthetic pigments and soluble carbohydrates contents in symbiosis with the M8349 IPRO genotype. Strains UFLA06-22 and UFLA06-24 were efficient in grain nitrogen accumulation in genotypes M8372 IPRO and M8349 IPRO. Principal component analysis shows the close positioning of several parameters in soybean genotypes inoculated with these strains. Our results demonstrate the potential of strains UFLA06-22 and UFLA06-24 for sustainable soybean production.