Mantell, A., Institute of Soils and Water, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
Frenkel, H., Institute of Soils and Water, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
Meiri, A., Institute of Soils and Water, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel

A two-year study was conducted in the Negev region of Israel, using the drip method, to determine the effect of four levels of water quality (EC =1.0, 3.2, 5.4 and 7.3 dS/m) in combination with three soil amendment treatments (gypsum spread on the soil surface along the drip laterals after planting, injection of H2SO4 into the water during each irrigation, and a control) on plant response, salt distribution in the soil profile, and soil sodification processes. Salinity did not reduce yields even at the highest level, in spite of sodium and chloride accumulation. The highest seed cotton yield (6.4 t/ha) was obtained with the local well water (EC =3.2 dS/m), indicating an optimal response to salinity. The addition of soil amendments during the irrigation season, although reducing exchangeable sodium accumulation near the emitter, endangers the next crop by increasing sodium accumulation under the plant row. It is therefore, recommended that the amendment be applied only before the winter. © 1985 Springer-Verlag.