Split application of liquid urea as a tool to nitrogen loss minimization and NUE improvement of corn - A review

Ahmmed Md Motasim1, 2, Abd. Wahid Samsuri2*, Arina Shairah Abdul Sukor2, and Adibah Mohd. Amin2
Nitrogen loss minimization is the main challenge to sustainable crop production and reducing environmental and economic losses. There is a new approach to urea application in liquid form (LU) so that the NH4+ can be evenly distributed throughout the soil profile, soil particles adsorb it and reduce the local substrate concentration inhibiting further transformation. Liquid urea has been hydrolyzed even prior to soil a pplication, whereas the urea in granulated urea (GU) must be hydrolyzed after application before it can be transformed to NH4+. Increased urea application frequency with lower doses can lower the NH4+concentration in soil compared to a single application. These mechanisms reduce the N loss potential and increase the N crop uptake potential of applied N by conforming to the proper synchronization between N availability and crop N demand as well as reduce N loss potential as NH3 volatilization, NO3- leaching and N2O emission. The inconsistent results and clarifications from various studies highlight the importance and benefits of relating the effect of LU application on N loss minimization, N availability and corn (Zea mays L.) yield. This review summarizes the potential ways of N losses and their management and provides the scientific reference to achieve sustainable corn yield and reduce N losses.
Keywords: Corn, liquid urea, NH3 volatilization, NO3- leaching, N2O emission, split application, Zea mays.
1University of Putra Malaysia, Faculty of Agriculture, Department of Land Management, Serdang 43400, Malaysia.
2Soil Resource Development Institute, Faridpur-7800, Bangladesh. *Corresponding author (samsuriaw@upm.edu.my).