Addition of Chemical and Natural Urease Inhibitors in Reducing Ammonia and Nitrous Oxide Losses

Abstract

To examine the reduction of ammonia (NH3) volatilisation, nitrous oxide (N2O) emission and production of grain yield in maize from urea fertiliser with the addition of chemical and natural urease inhibitors, a field experiment was conducted for one growing season of maize on sandy soil at Jabatan Pertanian Perak, Malaysia. Four replicates of three treatments: Urea (control), urea coated with thiosulfinate (UThiol) and urea coated with triamida N-(n-butil) tiofosforica, known as NBPT (UNBPT). After fertiliser application, NH3 volatilisation, N2O emission and grain yield were monitored at different timing. The NH3 volatilisation was determined using the Draeger tube method while N2O emission was discovered using the closed chamber technique. UNBPT showed the lowest NH3 volatilisation as compared with urea, followed by UThiol. For N2O emission, there is no significant difference between UNBPT and UThiol but both treatments recorded significant difference with Urea (control). The maize production exhibited a positive significant result by increasing the maize yield in UNBPT and UThiol than Urea (control) treatment. These results suggest that using natural inhibitor may have the most potential to reduce N losses and improve yield nearly as efficiently as chemical inhibitor.