Straw Returning Combined with Sulfur-Coated Urea Enhances Rice Yield and Nitrogen Use Efficiency

Strategic Insights -

Agricultural researchers from Jilin Agricultural University in Changchun, People's Republic of China, have discovered a significant increase in rice yield and nitrogen use efficiency by combining straw returning and sulfur-coated urea (SCU) application. The study, published in the journal Agriculture, found that this approach led to a substantial boost in grain yield and nitrogen recovery efficiency.

Key Takeaways:

  • The researchers conducted a two-year field experiment from 2022 to 2023 with three treatments: straw returning combined with conventional urea (SRU), no straw returning combined with SCU (NRS), and straw returning combined with SCU (SRS).
  • Straw returning combined with the application of SCU increased rice yield and nitrogen use efficiency significantly, with SRS treatments increasing grain yield by 14.61-16.22% and 4.14-7.35% compared to SRU and NRS, respectively.
  • The SRS treatment increased nitrogen recovery efficiency by 79.53% and 22.97%, nitrogen agronomic efficiency by 18.68% and 17.37%, and nitrogen partial factor productivity by 10.51% and 9.81% compared to SRU and NRS treatments, respectively.
  • The enhanced nitrogen use efficiency in SRS was driven by higher leaf area index, SPAD value, net photosynthetic rate, carbon metabolic enzyme activity, nitrogen metabolic enzyme activity, sucrose and nitrogen content in leaves, and nitrogen accumulation in plants during grain filling.
  • The improved yield in SRS was closely related to superior nitrogen use efficiency.

Statistics:

  • 14.61-16.22% increase in grain yield with SRS treatments compared to SRU.
  • 4.14-7.35% increase in grain yield with SRS treatments compared to NRS.
  • 79.53% increase in nitrogen recovery efficiency with SRS treatment compared to SRU.
  • 22.97% increase in nitrogen recovery efficiency with SRS treatment compared to NRS.
  • 18.68% increase in nitrogen agronomic efficiency with SRS treatment compared to SRU.
  • 17.37% increase in nitrogen agronomic efficiency with SRS treatment compared to NRS.
  • 10.51% increase in nitrogen partial factor productivity with SRS treatment compared to SRU.
  • 9.81% increase in nitrogen partial factor productivity with SRS treatment compared to NRS.

Sources:

  • Zhu, G., et al. (2025) "Straw Returning Combined with Application of Sulfur-Coated Urea Improved Rice Yield and Nitrogen Use Efficiency Through Enhancing Carbon and Nitrogen Metabolism." Agriculture, 15(14), 1554. (Agriculture - http://www.mdpi.com/journal/agriculture)
  • NewsRx. Reports Outline Agriculture Study Findings from Jilin Agricultural University (Straw Returning Combined with Application of Sulfur-Coated Urea Improved Rice Yield and Nitrogen Use Efficiency Through Enhancing Carbon and Nitrogen Metabolism). Life Science Weekly. August 12, 2025; p 4006.