Significance of Some Natural Amendments to Improve Soil Properties and Plant Growth

Many problems facing sandy, calcareous and heavy clay soils and restricts plant growth, nutrients availability and sustainable agriculture. Soil amendments are considered to be the most realistic soil management methods to improve soil chemical and physical properties. Improving some soil physical and chemical properties, study the correlation between soil properties and their effect on plant growth and nutrients uptake by faba bean plant (Vicia faba L. var.716) were the main purpose of this study. To achieve this purpose three factorial pot experiments were conducted by addition rates (0, 5 and10 ton. fed^-1 ) of farmyard manure (FYM), phosphate rock (PhR) and rice straw (RS) either alone or mixed to sandy, calcareous sandy loam and clay soils. Soils were incubated with the studied treatments for 15 days before planting. The main results showed that the addition rates of soil amendments led to slightly increase in soil salinity, total porosity and significant increase in organic matter content in the experimental soils. Bulk density and pH decreased with increased the rates of FYM and PhR either alone or mixed with RS. Decreasing in hydraulic conductivity in sandy and sandy loam soils, while it increases in clay soil. Generally, there are negative correlations between soil organic matter and both of hydraulic conductivity and bulk density in sandy and sandy loam soils, while, organic matter and hydraulic conductivity gave a positive effect in clay soil. Changes in soil properties had a positive effect of faba bean growth and macro nutrients uptake. The highest rates of the studied materials showed a significant increase in fresh and dry weight, NPK content and uptake of faba bean plant. Integrated use of the highest rates of FYM and PhR with RS were the best option for sustaining physical and chemical properties, enhancing faba bean growth and nutrients uptake of the studied soils.