Does the nitrogen application associated with Azospirillum brasilense inoculation influence corn nutrition and yield?

ABSTRACT The aim of this study was to investigate the synergistic effect between inoculation with Azospirillum brasilense and nitrogen application, thus enabling a higher efficiency of nitrogen fertilization, as evaluated by nutritional value, components production, and grain yield of irrigated corn. The experiment was conducted in Selvíria, MS, Brazil, under a no-till system, on an Oxisol in the Brazilian Cerrado. The experiment was set up in a randomized block design with four replications, in a 4 × 2 factorial arrangement: four patterns of nitrogen application [application of 30 kg ha-1 of N at sowing and 150 kg ha-1 as cover (30 + 150); 30 kg ha-1 of N at sowing, split into two applications of 75 kg ha-1 as cover (30 + 75 + 75); 180 kg ha-1 of N at sowing (180); and 150 kg ha-1 of N at sowing and 30 kg ha-1 as cover (150 + 30)]; with and without inoculation of the seeds with A. brasilense. The application of 30 kg ha-1 of N at sowing and a single application of 150 kg ha-1 or two applications of 75 kg ha-1 in topdressing, inoculated with Azospirillum brasilense provided better nutrition and development, with a positive reflection on irrigated corn grain yield in the Brazilian Cerrado.