Abstract

The capacity to transform atmospheric N₂ into ammonia, which initially enhanced the research, has become just one of the potentialities verified by diazotrophic bacteria, and today, it is known that these microorganisms produce various plant-growth-promoting substances. Due to the enormous data obtained so far, diazotrophic bacteria have the potential to be used as biofertilizers in different crops or grasses, it is expected that the application of this alternative fertilizer will reduce the need for N application in these crops, since an efficient nitrogen use is an essential factor for a sustainable agriculture and the world agribusiness. Investment in research and diffusion of biological nitrogen fixation (BNF), through multidisciplinary and integrated studies can bring great benefit to the planet, increasing food production, reducing the use of fossil fuels and the contamination of water resources, by decreasing the use of external sources of nitrogenous fertilizers. Therefore, this review will show the characteristics of diazotrophic bacteria (nitrogen-fixing), their way of acting with microorganism endophytes and their contribution when in association with grasses of economic importance.

Key words: Endophytic diazotrophic bacteria, inoculant, biological nitrogen fixation (BNF), grass.