Synergism of sulfur availability and agronomic nitrogen use efficiency

Authors: Agyin-Birikorang, Sampson; BOUBAKARY, CISSE - International Crops Research Institute For Semi-Arid Tropics (ICRISAT) - Nigeria; KADYAMPAKENI, DAVIE - University Of Florida; ADU-GYAMFI, RAPHAEL - University Of Ghana; Chambers, Rachel; TINDJINA, IGNATIUS - International Fertilizer Development Center (IFDC); FUSENI, ABDUL-RAHMAN - International Fertilizer Development Center (IFDC)

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/11/2023
Publication Date: 1/30/2024
Citation: Agyin-Birikorang, S., Boubakary, C., Kadyampakeni, D.M., Adu-Gyamfi, R., Chambers, R.A., Tindjina, I., Fuseni, A.A. 2024. Synergism of sulfur availability and agronomic nitrogen use efficiency. Agronomy Journal. 2024:1-12. https://doi.org/10.1002/agj2.21535.
DOI: https://doi.org/10.1002/agj2.21535

Interpretive Summary: Management strategies that exploits the synergistic interaction of nutrient elements to enhance nitrogen use efficiency (NUE) is needed economic and environmental reasons. A field study was carried out during the 2020–2022 growing seasons at six locations in three countries: two each in the USA, Ghana, and Mali using three sulfur (S) sources with different bioavailability levels (micronized elemental sulfur [MES], untreated elemental sulfur [ES], and ammonium sulfate [AS]); applied at five S application rates [(i) site-specific recommended S rate (SR), ¼ of the recommended S rate (25% SR) (iii) ½ of the recommended S rate (50% SR), (iv) ¾ of the recommended S rate (75% SR); and (v) 1¼ of the recommended S rate (125% SR)]; and a single N application rate (the site-specific recommended N application rate) to comprehensively elucidate the positive influence of S availability on nitrogen use efficiency (NUE). Specific objectives were to evaluate the influence of S availability on corn yield, N uptake, and NUE. Regardless of the S source and the experimental site, there was a highly significant strong positive correlation (r2 > 0.88) between the aboveground S and N uptake. Increasing the S application rate resulted in increasing apparent N recovery efficiency and agronomic NUE at each site, irrespective of the S source. The combined data showed that the efficiency of applied N fertilizer sources can be improved significantly by increasing S availability in soils. With the rising N fertilizer cost in recent times, N losses from the applied fertilizer are of great economic and environmental concern. Thus, increasing NUE is a desirable approach to increase returns on investment in crop production systems, safeguard against excessive N application, and reduce N losses that can disrupt the ecosystem function.

Technical Abstract: The importance of nitrogen (N) fertilization in crop production cannot be overemphasized because its deficiency significantly reduces crop yield. However, excessive use of N fertilizers has severe environmental consequences. Therefore, it is critical to implement N management strategies that could enhance the efficiency of N use in cropping systems. A field study was carried out during the 2020–2022 growing seasons at six locations in three countries: two each in the USA, Ghana, and Mali using three S sources with different bioavailability levels (micronized elemental sulfur [MES; 14.5% S, 32% N], untreated elemental sulfur [ES; 92% S], and ammonium sulfate (AS; 24% S, 21% N]); applied at five S application rates [(i) site-specific recommended S rate (SR), ¼ of the recommended S rate (25% SR) (iii) ½ of the recommended S rate (50% SR), (iv) ¾ of the recommended S rate (75% SR); and (v) 1¼ of the recommended S rate (125% SR)]; and a single N application rate (the site-specific recommended N application rate) to comprehensively elucidate the positive influence of S availability on nitrogen use efficiency (NUE). Specific objectives were to evaluate the influence of S availability on corn yield, N uptake, and NUE. For the entire duration of the study, the agronomic effectiveness of the S sources followed the order: AS = MES > ES at all experimental sites, and the that of the application rate followed the order: 125% SR = SR > 75% SR > 50% SR > 25% SR > control with AS. With MES it was in this order: 125% SR = SR = 75% SR > 50% SR > 25% SR = control, and with ES the following order was observed: 125% SR > SR > 75% SR = 50% SR = 25% SR = control. Regardless of the S source and the experimental site, there was a highly significant strong positive correlation (r2 > 0.88) between the aboveground S and N uptake. increasing the S application rate resulted in increasing apparent N recovery efficiency and agronomic NUE at each site. The combined data show that the efficiency of applied N fertilizer sources can be improved significantly by increasing S availability in soils. With the rising N fertilizer cost in recent times, N losses from the applied fertilizer are of great economic and environmental concern. Thus, increasing NUE is a desirable approach, not only to increase returns on investment in crop production systems, prevent excessive N application, and reduce N losses that can disrupt the ecosystem function, but will also meet the increasing demand for food and fiber.