Inoculation with Azospirillum brasilense Improves Nutrition and Increases Wheat Yield in Association with Nitrogen Fertilization

The management of nitrogen fertilization is performed in order to ensure adequate productivity, and depending on the N dynamics in the soil, large amount of N is added to the soil, raising production cost for the farmers. Considering the benefits attributed by seed inoculation with Azospirillum brasilense (diazotrophic bacteria), with emphasis on biological nitrogen fixation (BNF), greater development of the root system, and, consequently, greater absorption of water and nutrients, it infers that inoculation can improve crop performance allowing greater efficiency of nitrogen fertilization. Thus, the research that evaluates nutritional status and wheat yield, in terms of nitrogen rates in association with inoculation with A. brasilense is important. We found that increment of N rates in association with A. brasilense inoculation increases the wheat yield up to 139 kg ha−1 N, whereas without this inoculation linear increase occurred with lower maximum yield of wheat. That is, the inoculation afforded higher grain yield applying less nitrogen fertilizer in topdressing. This research demonstrated that inoculation with A. brasilense associated with nitrogen fertilization in topdressing is beneficial to nutrition and wheat yield. Therefore, inoculation is a low-cost technique, easy to apply and use, and nonpolluting, which fall within the desired sustainable context in actuality