Nutrient use efficiency

Abstract

Sustainable crop production delivering high yield to meet ever increasing demand for food requires optimum use of fertilizers (nutrients) by crops. Since fertilizers are costly both financially and environmentally, increasing efficiency of applied fertilizers is a prerequisite. Nutrient use efficiency (NUE) may be defined as yield per unit fertilizer input or in terms of recovery of applied fertilizer. The most appropriate expression of NUE is, however, determined by the question being asked and often by the spatial or temporal scale of interest for which reliable data are available. Analysis of global temporal trends in NUE for N, P and K showed that partial factor productivity (units of crop yield per unit of applied nutrient) and partial nutrient balance (units of nutrient uptake per unit of applied nutrient) for Africa, North America, Europe and the EU-15 are trending upwards, while in Latin America, India and China, they are trending downwards. Typical NUE values for crops are best set locally within the appropriate cropping system, soil, climate and management contexts. Development of new cultivars with higher NUE, coupled with the best management practices, will contribute to sustainable agricultural systems. Improvement in NUE thus requires simultaneous consideration of multiple aspects like crop improvement as well as crop management involving a multidisciplinary approach.