Slow‐release peat‐urea fertilizer increased sweet corn yield and nitrogen use efficiency compared to urea

Abstract Nitrogen (N) use efficiency of urea is often low, resulting in inefficient N utilization. Again, peat, a high organic carbon (OC)‐containing soil, is considered a problematic soil. However, enriching peat with urea may release fertilizer N slowly, and its application to agricultural soil can sequester OC in the soil. So, this experiment was undertaken to evaluate the effects of peat‐urea (PU) fertilizer on N release, post‐harvest soil health, growth, yield, N uptake, and use efficiency of sweet corn ( Zea mays L.) compared with urea. Two PU (PU‐I and PU‐II) granules were formulated, having a C/N ratio of 1.95 and 2.61, respectively. The size, moisture content, and crush strength of PU granules reflect their feasibility for field application. The Fourier transform infrared analysis confirms the urea‐N loading in the peat matrix. The N release was slower from PU than from urea. In the pot trial, urea, PU‐I, and PU‐II were applied at 100% and 75% of the recommended dose of N. PU application resulted in significantly higher chlorophyll, cob yield, and N uptake by sweet corn compared to the sole application of urea. Compared to urea, application of PU increased the cob yield by 23% and N uptake by 21%. The higher N uptake in PU‐treated plants facilitated 15.16% higher N use efficiency and 13.85% higher fertilizer N use efficiency of sweet corn than urea. In addition, the total N and OC in the post‐harvest soil also increased considerably due to PU application compared to urea.