Host specificity among Bradyrhizobium japonicum strains and soybean cultivars with late maturation cycle

Abstract

In a greenhouse experiment, the host specificity among strains of Bradyrhizobium japonicum and the soybean cultivars Doko, Cristalina, EMGOPA-301, EMGOPA-303 and IAC-8, recommended for the state of Goiás, Brazil, was studied. The inoculation treatments were: no inoculation, CB 1809, R54a, 965, 29W, SEMIA 587, and the mixture of those strains. A dark-red latosol under cerrado vegetation was used. Plants were collected at the filling pods stage and, except for N contents in the shoots, there were no differences among cultivars in the various parameters. Effects were observed from inoculated strains, with great nodulation generally being associated with lower shoot N content. The most effective strains were CB1809 and R54a. As related to N shoot content, Cristalina performed best. There was no host specificity among B. japonicum strains and soybean cultivars.