Two field experiments were carried out at El-Hussynia Research Station, Port Said Governorate, during two successive winter seasons (2012|2013 and 2013|2014), to study the effect of sugar industrial wastes (filter mud and sugar lime); gypsum and elemental sulphur which was added alone or combined with them under different irrigation intervals on some soil physical and chemical properties and water use efficiency. The treatments that subjected in this study were eight treatments; untreated i.e, control, gypsum at a rate of 4 ton fed-1, elemental sulphur at a rate of 0.5 ton/fed, industrial wastes (mixture of filter mud and sugar lime 2:1 w/w) at a rate of 4.5 ton/fed as well as their combination under two irrigation intervals of 12 and 18 days.
With regard to soil physical properties, data revealed that application of amendments and/or sugar industrial wastes under two irrigation intervals increased the aggregates size distribution particularly of (2-1 mm) in diameter and total water stable aggregates. At the same time these treatments decreased the fine aggregates size ( >0.125 mm) in diameter. Consequently, infiltration rate and available water were increased while bulk density was decreased, particularly in the surface layer (0-20 cm) in the presence of applied gypsum+ sulphur combined with (filter mud + sugar lime) under 12 days of irrigation interval as compared with the other treatments.
As for the chemical properties, data showed that pH, EC, ESP and O.M were positively affected either by applied gypsum, sulphur and/or filter mud + sugar lime particularly in the surface layer (0-20 cm) under 12 days of irrigation interval as compared with other treatments. Also, the grain content of the three nutrients elements (N P and K) was increased.
Wheat grain yield, straw yield and water use efficiency were enhanced in response to application of amendments under irrigation intervals as compared with the untreated soil.
The improvement of some soil physical and chemical properties as well as increasing wheat yield and water use efficiency, was achieved for interaction between 1.5 ton gypsum + 0.5 ton sulphur + 2.0 ton filter mud + 1.0 ton sugar lime per feddan under 12 days irrigation interval.