ABSTRACT
An extremely important aspect of the problem of nutrient acquisition concerns the efficiency of the process and the influence of environmental damage on it. Moreover, the definition of "efficiency" applied to plant nutrients. It has long been questioned, owing to the contrasting methods of evaluation of both plant productivity and uptake of inorganic ions released by the mineralization of the soil organic fraction or by the supply of mineral fertilizers. The region of roots where microorganisms are most abundant is usually immediately behind the root hair zone, and the absorption of nutrients can be modified by these organisms in various ways. The pH of the root environment is a factor in the efficiency of processes of absorption, particularly when more than one form of the ion exists. Most crop plants are sensitive to the presence of salt in their root environment whether naturally occurring or induced by irrigation with semisaline water.
