Design and Development of Controlled Release Fertilizers (CRFs) Technology for Enhancing Nutrient Use Efficiency

Abstract

The major problem faced by the agricultural practices world over is fertilizer use efficiency, particularly nitrogen fertilizer-use efficiency. The excess use of the chemical fertilizers is one of the major causes of the environmental pollution. Accumulation of nitrate, phosphate, metals, ammonia, and nitrous oxide in ecosystems through fertilizer has become a huge concern for health and environmental aspects. A controlled-release fertilizer (CRF) is a granulated fertilizer that releases nutrients gradually into the soil (i.e., with a controlled release period). Controlled-release fertilizer is also known as controlled-availability fertilizer, delayed-release fertilizer, metered-release fertilizer, or slow-acting fertilizer. Usually CRF refers to nitrogen-based fertilizers. Slow- and controlled-release involve only 0.15% (5,62,000 tons) of the fertilizer market. Fertilizer and plant nutrition research should be established to prevent the environmental pollution and at the same time meet the productivity and yield requirements. Controlled-release fertilizers can be used to improve the efficiency of fertilizers and should be improved and refined to reduce the environmental contamination.