The world-wide shortage of plant production menacing the survival of many people demands for more and better research, particularly on how to increase food and where it is most needed. Major problems of international concern for the scientific community are the availability in soil media of macro and micro nutrients and the efficiency of nutrient uptake by plant roots, the interactions between nutrients and other factors, the distribution of nutrients in different plant species, biochemical functions of nutrient elements, and their contribution to plant growth, yield and product quality....