@article{citation_3935, abstract = {
Nitrogen (N) is an essential but generally limiting nutrient for biological systems. Development of the Haber-Bosch industrial process for ammonia synthesis helped to relieve N-limitation of agricultural production, fueling the Green Revolution and reducing hunger. However, the massive use of industrial N-fertilizer has doubled the global N-cycle with dramatic environmental consequences that threaten planetary health. Consequently, there is an urgent need to reduce losses of reactive-N from agriculture, while ensuring sufficient N-inputs for food security. Here, we review current knowledge related to N use efficiency (NUE) in agriculture and identify research opportunities in the areas of agronomy, plant breeding, biological N fixation (BNF), soil N-cycling, and modeling to achieve responsible, sustainable use of N in agriculture. Amongst these opportunities, improved agricultural practices that synchronize crop N-demand with soil N-availability are low-hanging fruit. Crop breeding that targets root and shoot physiological processes will likely increase N uptake and utilization of soil N, while breeding for BNF effectiveness in legumes will enhance overall system NUE. Likewise, engineering of novel N-fixing symbioses in non-legumes could reduce the need for chemical fertilizers in agroecosystems but is a much longer-term goal. The use of simulation modeling to conceptualize the complex, interwoven processes that affect agroecosystem NUE, along with multi-objective optimization, will also accelerate NUE gains.
}, author = {M Udvardi and F E Below and M J Castellano and A J Eagle and K E Giller and J K Ladha and X Liu and T M Maaz and B Nova-Franco and N Raghuram and G P Robertson and S K Roy and M Saha and S Schmidt and M Tegeder and L M York and J W Peters}, title = {A research road map for responsible use of agricultural nitrogen}, year = {2021}, note = {LTER ack 1832042}, journal = {Frontiers in Sustainable Food Systems}, pages = {660155}, volume = {5}, doi = {10.3389/fsufs.2021.660155} }