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      Biological nitrogen fixation and prospects for ecological intensification in cereal-based cropping systems


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          The demand for nitrogen (N) for crop production increased rapidly from the middle of the twentieth century and is predicted to at least double by 2050 to satisfy the on-going improvements in productivity of major food crops such as wheat, rice and maize that underpin the staple diet of most of the world’s population. The increased demand will need to be fulfilled by the two main sources of N supply – biological nitrogen (gas) (N 2) fixation (BNF) and fertilizer N supplied through the Haber-Bosch processes. BNF provides many functional benefits for agroecosystems. It is a vital mechanism for replenishing the reservoirs of soil organic N and improving the availability of soil N to support crop growth while also assisting in efforts to lower negative environmental externalities than fertilizer N. In cereal-based cropping systems, legumes in symbiosis with rhizobia contribute the largest BNF input; however, diazotrophs involved in non-symbiotic associations with plants or present as free-living N 2-fixers are ubiquitous and also provide an additional source of fixed N. This review presents the current knowledge of BNF by free-living, non-symbiotic and symbiotic diazotrophs in the global N cycle, examines global and regional estimates of contributions of BNF, and discusses possible strategies to enhance BNF for the prospective benefit of cereal N nutrition. We conclude by considering the challenges of introducing in planta BNF into cereals and reflect on the potential for BNF in both conventional and alternative crop management systems to encourage the ecological intensification of cereal and legume production.


          • Biological N fixation (BNF) is the single largest global input of reactive nitrogen.

          • Critical review of current knowledge of BNF in cereal-based cropping systems.

          • Global and regional estimates of the nutrient supply contribution of BNF.

          • Discussion of the challenges associated with introducing in planta BNF into cereals.

          • Overview of opportunities to enhance use of BNF in ecological intensification.

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          Most cited references345

          • Record: found
          • Abstract: found
          • Article: found

          Planetary boundaries: Guiding human development on a changing planet

          The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries—climate change and biosphere integrity—have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.
            • Record: found
            • Abstract: not found
            • Article: not found

            How a century of ammonia synthesis changed the world

              • Record: found
              • Abstract: found
              • Article: not found

              A draft sequence of the rice genome (Oryza sativa L. ssp. indica).

              J. Yu (2002)
              We have produced a draft sequence of the rice genome for the most widely cultivated subspecies in China, Oryza sativa L. ssp. indica, by whole-genome shotgun sequencing. The genome was 466 megabases in size, with an estimated 46,022 to 55,615 genes. Functional coverage in the assembled sequences was 92.0%. About 42.2% of the genome was in exact 20-nucleotide oligomer repeats, and most of the transposons were in the intergenic regions between genes. Although 80.6% of predicted Arabidopsis thaliana genes had a homolog in rice, only 49.4% of predicted rice genes had a homolog in A. thaliana. The large proportion of rice genes with no recognizable homologs is due to a gradient in the GC content of rice coding sequences.

                Author and article information

                Field Crops Res
                Field Crops Res
                Field Crops Research
                Elsevier Scientific Pub. Co
                01 July 2022
                01 July 2022
                : 283
                : 108541
                [a ]Department of Plant Sciences, University of California, Davis, CA, USA
                [b ]Commonwealth Scientific and Industrial Research Organisation, Canberra, Australia
                [c ]The Energy and Resources Institute, New Delhi, India
                [d ]Krishi Gobeshona Foundation, Dhaka, Bangladesh
                [e ]International Maize and Wheat Improvement Center, New Delhi, India
                [f ]International Maize and Wheat Improvement Center, Dhaka, Bangladesh
                Author notes
                [* ]Correspondence to: International Maize and Wheat Improvement Center (CIMMYT)- Bangladesh, House 10B. Road 53, Gulsha-2, Dhaka 1213, Bangladesh. t.krupnik@ 123456cgiar.org
                S0378-4290(22)00112-5 108541
                © 2022 The Authors

                This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

                : 7 August 2021
                : 29 March 2022
                : 3 April 2022
                Loomis Review

                nitrogen cycle,symbiotic nitrogen fixation,non-symbiotic nitrogen fixation,legumes,diazotrophs,crop nitrogen nutrition


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