Plants depend for their micronutrient needs on their availability in the rooting zone. This is a function of their total content, derived from the soilforming minerals in the parent material, and the several soil chemical and physical properties. The latter determine the dynamics of the equilibrium between the total content of a micronutrient in the soil and its labile pool, from which they are acquired by plant roots. The acquisition of micronutrients from the labile pool is also affected by biological activities in the soil, the physical factors of the environment (temperature, pH, light intensity, etc.) and cultural practices. Genetic attributes and stress disposition of plants also influence the acquisition of micronutrients. Sustained growth and yield of crop plants is a function of the interactive influences of the soil, plant and environmental factors. Any one or more of these factors may adversely affect the availability of micronutrients and reduce it to deficiency concentrations.