Effect of the Continuous Use of Sodium and Bicarbonate-Rich Irrigation Water with Gypsum and Farmyard Manure on Soil Properties and the Yield of Wheat in a Fine Loamy Soil

Effect of the use of a sodic water (EC= 4 dS/m; SARiw=26, RSC=l5) alone and in conjunction with graded doses of gypsum (G) and FYM was investigated by growing wheat for eight years in sandy clay loam soil in a wheat-fallow sequence which received 290 and 345 cm of irrigation and rain water, respectively. Soil(0–15 cm) ESp in no-gypsum and FYM @ 25 t/ha/year was maximum (38–40) after the irrigation phase. Soil ESp and EC decrejsed by 20 to 30% and 47 to 50% respectively after monsoon. The highest ESp developed in 0–60 cm soil profile was not more than 50% over and above that of SARiw even in no-gypsum treatment. Gypsum addition decreased soil ESP in proportion to the neutralization of original SARiw. Wheat yield was not affected significantly in seven out of eight years by any of the treatments. The steady state infiltration rate was reduced under FYM @ 25 t/ha/year treatment even compared with no-gypsum plot, whereas it was considerably enhanced in gypsum applied plots relative to control.