Improving Nutrient Use Efficiency by Exploiting Genetic Diversity of Crops

Abstract

Low nutrient use efficiency by crops needs to be increased to have lower unit crop production costs, higher economic returns and minimal negative environmental impact. In the twenty-first century, nutrient-efficient plants will play a major role in increasing crop yields compared to the twentieth century, mainly due to limited land and water resources available for crop production, higher cost of inorganic fertiliser inputs, declining trends in crop yields globally and increasing environmental concerns. Many studies have reported large genetic variation for nutrient efficiency in different crop species and cultivars. The efficient cultivars gave higher yield under nutrient stress and had higher agronomic use efficiency (AUE) than less efficient cultivars. The variation in nutrient efficiency of different crop cultivars was due to both their capability to use absorbed nutrients to produce yield and to their capacity to take up more nutrient per unit soil. The indication of higher expression of ammonium transporter, cytochrome oxidase and asparagine synthetase in potato leaves had been reported to be used as parameters to screen potato genotypes for high metabolism, utilisation, transport and storage of N. There is a need to establish linkage of nutrient efficiency with root and shoot parameters/DNA markers/genes to have/breed multi-nutrient-efficient crop varieties.