Growth and yield of common bean co-inoculated with Rhizobium, Azospirillum and Bradyrhizobium in the field

Abstract

Biological nitrogen fixation is important sustainable management in common bean crop. This
work evaluated the effect of inoculation and coinoculation of rhizobia and growth promoting
bacteria on common bean (Phaseolus vulgaris) at field conditions. The experiment was conducted
in Macaé – RJ, a traditional bean cultivation area. Five N sources were evaluated:
absolute control; nitrogen control (80 kg N ha-1); rhizobial inoculation; rhizobial + Bradyrhizobium
coinoculation; rhizobial + Azospirillum coinoculation. Shoot, root and nodule dry weight
at flowering, and grain yield at maturity, were evaluated. No significant effect of treatments was
observed for all parameters. Native rhizobial population was effective for nodulation and grain
yield, since the absolute control reached 89% of the yield of the nitrogen control. Bradyrhizobium
coinoculation reached 91% of the yield of nitrogen control, while sole rhizobial inoculation
reached 86%.