
%0 Journal Article
%A Mehanni, AH 
%A West, DW 
%T Effect of nitrogen fertilizer on yield of perennial pastures irrigated with saline water
%J Australian Journal of Experimental Agriculture
%D 1992/12/01
%V 32
%N 8
%P 1087-1093
%K 
%R https://doi.org/10.1071/EA9921087
%U https://www.publish.csiro.au/paper/EA9921087 
%X This study examines the interaction between salinity and nitrogen (N) fertiliser in perennial pastures growing in the Shepparton Irrigation Area of northern Victoria. In a greenhouse experiment, perennial ryegrass was irrigated with 5 concentrations of sodium chloride (100-6000 mg NaCl/L) and fertilised with 5 concentrations of N (25-800 mg/L). Nitrogen at 200 mg/L was optimum for dry matter yield; at N concentrations >200 mg/L, yield declined. Dry matter yield was greater at 750 mg NaCl/L than at 100 mg NaCl/L but was reduced with further increases in salinity. Significant interactions between salinity and N were recorded for dry matter, and for chloride, Na, potassium, and magnesium concentrations in perennial ryegrass. In a field experiment, the growth of mixed perennial ryegrass-white clover pastures irrigated with saline water [53000 mg/L of total dissolved solids (TDS)] also responded to N applications. With no added N, yield (2-year average) decreased from 16 630 to 11 277 kg DM/ha (32% decrease) with an increase in salinity from 100 to 3000 mg TDS/L. With 150 kg N/ha, the average yield was 17681 kg DM/ha at 100 mg TDSL and 14 123 kg DM/ha at 3000 mg TDS/L (20% decrease). Form of N (calcium nitrate, ammonium nitrate, or urea) had no significant effect on yield at 150 kg N/ha. Application of urea at 150 kg N/ha to pastures irrigated with water of salinity up to 3000 mg TDS/L would be economically justifiable. 
