Performance of Wheat in Five Soils of Different Textures under Freshwater and Wastewater Irrigation

This study investigated the effects of five soils of different textures on wheat cultivation under irrigation with freshwater (FW) and municipal wastewater (WW). The experimental design was a split-plot with irrigation water quality as main factor and soil texture as sub-factor in three replications. These factors respectively comprised 2 and 5 treatments. Soil texture significantly (p≤0.05) influenced plant height, leaf area index (LAI), spike length, number of grains per spike, above ground dry matter (ADM), grain yield, straw yield and biomass yield of wheat in most cases both under FW and WW irrigation. The harvest index (HI) of wheat responded significantly under FW irrigation only. Under FW, treatment T5 (silt loam) produced the highest grain yield (4.2 t ha–1) followed by T3 (loam-1) (3.1 t ha–1); the lowest yield (2.0 t ha–1) was in the control treatment, T1 (loamy sand). Under WW, treatment T2 (sandy loam) produced the highest grain yield (5.0 t ha–1) followed by T4 (loam-2) (4.5 t ha–1) both of which are statistically similar; the lowest yield (3.4 t ha–1) was in the control treatment. Treatments T2 and T4 provided the highest straw yield (5.6 t ha–1) and treatment T2 provided the highest biomass yield (10.6 t ha–1), both under WW; both T2 and T4 produced invariant biomass yields. Compared to other treatments, T2 and T4 gave statistically similar but significantly higher water productivity with respect to straw and grain yields. The lowest water productivity was in treatment T1 under both water qualities. The results of this study provided sound criteria in selecting suitable lands for wheat cultivation based on irrigation water quality, specifically in alluvial plains where soil texture is prone to high variations. Also, the observed facts of improved productivity of lower quality coarse-textured soils due to addition of easily available and inexpensive clay would provide guidance to bring unproductive sandy soils under production by clay amendments.