Potassium and Zinc Management in Rice (Oryza sativa L.) based on 4R concept - A Review

Plant growth is highly influenced by the nutrient supply from soil and the external application of fertilizers. Plants must receive essential nutrients like N, P, K, S and micronutrients for optimum plant growth and development. In current agricultural practices, especially, in cereal-based cropping systems, the soil nutrient balance like potassium and zinc are disturbed to the negative side due to intensive exploitation of native soil nutrients and low external input application. Employing 4R nutrient stewardship (right time, right dose, right source and right method) in soil nutrient management will ensure higher yield, nutrient uptake, nutrient use efficiency, increase in farm income, and minimal damage to the environment through its demand-specific supplement and management. Equilibrium between different pools of nutrients is the major driving factor for nutrient supply and demand in the soil which can be compensated by the external supply of nutrients through the 4R approach. Adoption of 4R stewardship in rice-based systems will ensure the attainment of maximum yield and nutrient use efficiency provided all other growth factors are in optimal supply and will assist in attaining self-sufficiency in rice production.