Biotechnological approaches to develop nitrogen-fixing cereals: A review Boujenna, Asma García Del Moral Garrido, Luis F. Biological nitrogen fixation Nitrogenase Nif genes O2 tolerance Plastids Mitochondria Plant growth-promoting rhizobacteria Funding: This work has been funded by the Junta de Andalucia through the research group AGR123. Agricultural yields are often limited by nitrogen (N) availability, especially in countries of the developing world, whereas in industrialized nations the application of chemical N fertilizers has reached unsustainable levels that have resulted in severe environmental consequences. Finding alternatives to inorganic fertilizers is critical for sustainable and secure food production. Although gaseous nitrogen (N2) is abundant in the atmosphere, it cannot be assimilated by most living organisms. Only a selected group of microorganisms termed diazotrophs, have evolved the ability to reduce N2 to generate NH3 in a process known as biological nitrogen fixation (BNF) catalysed by nitrogenase, an oxygen-sensitive enzyme complex. This ability presents an opportunity to improve the nutrition of crop plants, through the introduction into cereal crops of either the N fixing bacteria or the nitrogenase enzyme responsible for N fixation. This review explores three potential approaches to obtain N-fixing cereals: (a) engineering the nitrogenase enzyme to function in plant cells; (b) engineering the legume symbiosis into cereals; and (c) engineering cereals with the capability to associate with N-fixing bacteria. 2022-01-27T09:19:42Z 2022-01-27T09:19:42Z 2021-10-27 info:eu-repo/semantics/article Boujenna A; Garcia del Moral, LF (2021). Biotechnological approaches to develop nitrogen-fixing cereals: A review. Spanish Journal of Agricultural Research, Volume 19, Issue 4, e08R01. [https://doi.org/10.5424/sjar/2021194-18346] http://hdl.handle.net/10481/72512 10.5424/sjar/2021194-18346 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria