Contrasting response of wheat to one-time root zone fertilization of ordinary and polymer coated urea for grain yield and nitrogen use efficiency

Appropriate fertilization methods and high efficiency of N fertilizers are crucial to achieve high yields and curtail N losses. This study documented the comparative effectiveness of one-time root zone fertilization (ORZF) and polymer coated urea (PCU) as alternate ways to enhance grain yield and reduce potential N losses in wheat. The study was planned using two N fertilization methods [split-surface broadcasting (SSB) and ORZF], two N sources [ordinary urea (OU) and PCU] along with a control treatment following a completely randomized design. The SSB proved more efficient by showing 9% higher grain yield than ORZF, irrespective of N sources. The PCU resulted in 8% and 10% more grain yield than OU when applied through SSB and ORZF method, respectively. Likewise, maximum total N uptake was achieved with PCU than OU with an increment of 15% (SSB) and 7% (ORZF). The NUE indices remained statistically similar between methods, however, SSB showed higher values than ORZF. On the other hand, N sources had a pronounced effect on these indices which improved considerably with the PCU than OU under both methods. Maximum N losses were quantified with the OU in both methods (56% in SSB, and 54% in ORZF). Conversely, these losses were significantly reduced to 42% in SSB and to 48% in ORZF with the addition of PCU. The findings suggested that the application of PCU can be an effective way to improve wheat productivity and reduce N losses but ORZF is not a suitable alternative to SSB for wheat crops.