Maize inoculated with diazotrophic bacteria. (A) Hydroponic experiment. (B) Measurement of colonization levels in maize during the experiment. Two biological replicates were used for each treatment. The error bars represent the standard deviation. CT: mock sample; Hs: inoculation with H. seropedicae; Ab: inoculation with Azospirillum brasilense; d: days after inoculation.