This study aimed to evaluate different intervals between chemical desiccation or cut Brachiaria brizantha, inoculated or not with arbuscular mycorrhizal fungi, and soybean sowing. B. brizantha was sown in pots, in the presence or absence of Glomus etunicatum, Glomus fasciculatum and Scutellospora heterogama mixture. The grass was sown in different periods so as to present the same developmental stage at the time of chemical desiccation or cut, at 7, 14, 21 or 28 days before soybean sowing (DBS). Soybean sown in a single time was inoculated to a mixture of Bradyrhizobium strains (SEMIA 5019, SEMIA 5079, SEMIA 5080, and SEMIA 587). The soybean plant was evaluated at the flowering stage. No herbicide effect was verified on the soybean when desiccation was performed at 14, 21 or 28 DBS; however, at all times, soybean developed better when B. brizantha was mycorrhizal fungi inoculated. Desiccation at 7 DBS increased of leaf area, trifoliate and nodule number, and soybean leaf dry biomass, compared to the cut treatment. However, at this same time, mycorrhizal colonization and soybean root volume were found to decrease.
Bradyrhizobium; herbicide; arbuscular mycorrhiza; nodulation
