Mainly seven types of chemical fertilisers are used in Nepal. These are Urea, Diammonium Phosphate (DAP), Murate of Potash (MOP), Ammonium Sulphate (AS), Single Super Phosphate (SSP), Ammonium Phosphate Sulphate (APS) and NPK. The use of chemical fertilisers has an increaseing trend.[12] Among them, Urea and DAP is the most used ones.[9]