Nitrogen (N) is one of most important nutrients for crop production, which makes up 1%-5% of total plant dry matter (Marschner, 2012). Due to the limited availability of N in soil, application of N fertilizers has...Nitrogen (N) is one of most important nutrients for crop production, which makes up 1%-5% of total plant dry matter (Marschner, 2012). Due to the limited availability of N in soil, application of N fertilizers has been an important agronomic practice to increase crop yield. However, over-application of N fertilizers has caused pollution of N in soil, water and air. It was estimated that the nitrogen use efficiency (NUE, the total biomass or grain yield produced per unit of applied fertilizer N) in cereal crops is as low as 33% (Raun and Johnson, 1999). Therefore, improving NUE together with reducing application of N fertilizers is an important issue for environment and sustainable production of crops. This is especially important for rice, which is a staple food for half population in the world.展开更多
文摘Nitrogen (N) is one of most important nutrients for crop production, which makes up 1%-5% of total plant dry matter (Marschner, 2012). Due to the limited availability of N in soil, application of N fertilizers has been an important agronomic practice to increase crop yield. However, over-application of N fertilizers has caused pollution of N in soil, water and air. It was estimated that the nitrogen use efficiency (NUE, the total biomass or grain yield produced per unit of applied fertilizer N) in cereal crops is as low as 33% (Raun and Johnson, 1999). Therefore, improving NUE together with reducing application of N fertilizers is an important issue for environment and sustainable production of crops. This is especially important for rice, which is a staple food for half population in the world.