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.