Diversity of Bradyrhizobium populations associated to soybean-maize rotations in Québec, Eastern Canada, and their potential to improve growth of both plant species

► Bradyrhizobial diversity of 255 strains from soybean-maize rotations in Québec. ► Six IGS types; 40% and 30% in IGS I and III; plant species: no effect on diversity. ► Reference strains and commercial inoculants in IGS III and VI. ► 25 strains more effective symbiotically than reference strain (532c) with soybean. ► 20 PGPR strains with 10-20% increase in maize SDW.