Effect of Amendment Type and Leaching Requirements on Some Properties of Different Textured Soils Cultivated with Tomato (Solanum lycopersicum L.)

Abstract

 A pot experiment was conducted in 2024 under lath house conditions at the Department of Soil and Water Resources, College of Agriculture, University of Basrah (Karma- Ali site), to investigate the effect of adding soil amendments and different leaching requirements on the salinity of soils with varying textures and the concentrations of selected soluble ions in the soil solution of tomato-planted soils. Two soil textures were used—clay loam and sandy loam—along with two types of organic amendments (compost and cattle manure) in addition to a control treatment (no amendment). Two levels of leaching requirement (10% and 20% above field capacity) were also applied. The amendments were thoroughly mixed with the surface layer of the soil before planting tomato seedlings (Solanum lycopersicum L.), and soil moisture was maintained at field capacity throughout the experiment. Standard agronomic practices, including irrigation and fertilization, were carried out according to the treatment design. After 60 days of growth, the plants were harvested, and soil samples were collected to determine electrical conductivity (E.C.) and the concentrations of sodium (Na⁺) and chloride (Cl⁻) soluble ions in the soil solution.The results showed that the application of organic amendments significantly reduced soil electrical conductivity at the end of the experiment, from 6.11 and 1.88 dSm⁻¹ to 4.18 and 1.66 dSm⁻¹ for the clay loam and sandy loam soils, respectively. The reduction was more pronounced with compost compared to cattle manure. Furthermore, the 20% leaching requirement was more effective in reducing soil E.C., reaching a minimum value of 2.63 dSm⁻¹. Sodium and chloride ion concentrations in the soil leaching also decreased with amendment application, with the compost treatment combined with 20% leaching in sandy loam soil achieving the lowest concentrations of 37.6 and 99.0 mmol L⁻¹ for Na⁺ and Cl⁻, respectively.The Conclusion of this study is findings suggest that compost combined with a 20% leaching requirement can be effectively used in the reclamation of saline-affected soils and in improving their physical and chemical properties to create a more favorable environment for plant growth.