Efficiency of Zinc in Plants, its Deficiency and Sensitivity for Different Crops

Abstract
Optimal crop nutrition is a significant factor in increasing agricultural vintage and quality of products. Zinc (Zn) is an immobile important micronutrient, which is taken up by plants in Zn2+ form to complete their life cycle efficiently. It plays a critical metabolic role in plants and is an important constituent of proteins and other large-molecules, and serves as structural and functional unit, or controlling cofactor for a wide range of enzymes. The Zn is needed in small and in appropriate amounts for plants main physiological processes to work normally. These processes play critical roles in photosynthetic activity of plants and forming carbohydrates, synthesis of protein, reproduction and seed development, growth, and disease protection. After Zn deficiency in plants, these physical functions are decreased, and plant health and productivity suffer greatly, subsequent in reduced production or even failure of crops and often bad quality of crop products. Plant Zn deficiencies occur on variety of soils and are severe due to a combination of symptoms like chlorosis, resetting, dieback and suppressed or irregular vegetative development. In addition, various crops require varying amount of Zn. So the knowledge regarding this is not up to date. The present review discusses the Zn importance in plants, its deficiency in soil and required level of Zn for crops.