Salt Profile Variations and Wheat Growth under Irrigation with Highly Saline Waters on Coarse Loamy Soils in South-Western Haryana

Seasonal variations in soil profiles were studied over a two year period in areas where highly saline subsoil waters are the only source of supplemental irrigation. Irrigation with saline waters of 15000–17000 micromhos/cm EC having Na/Ca+Mg ratio of about 1.0, which were reportedly in use for the last 6–15 years for growing wheat and barley crops only, resulted in wheat grain yield of 20–35 q/ha in sand to loamy sand, well drained, deep water table seated soils which received more than 500 mm rainfall annually, when the fields were kept fallow during the intervening monsoon. Salts accumulated in the preceding crop season were leached out during rains and saline soils (ECe=14.0–33.6 mmhos/cm) became completely non-saline up to a depth of at least 60 cm before the next wheat season commenced. Salt profiles of Na—Mg—Ca—SO4—Cl type ofter wheat harvest became Ca-Mg—Na—SO4—Cl type up to a depth of 75 cm and Na-Mg—Ca—SO4-Cl type beyond 90 cm after the monsoon. Generally the SAR of the soil did not approach the SAR of the irrigation water even up to a depth of 180 cm.