Azospirillum is a free-living nitrogen-fixing bacterium which can colonize, by adhesion, the root surface or the intercellular spaces of the host plant roots.
They associate with economically important cereals and other grasses to promote plant growth by several mechanisms including nitrogen fixation and phytohormone (auxins, gibberellins, cytokinins etc.) production.Azospirillum brasilense and Azospirillum lipoferum are widely used as biofertilizers.
