ABSTRACT
Cotton is one of the important cash crops and a fiber crop most widely grown and the highest yielding as well. Cotton fiber is woven to be the fabrics commonly used in our daily life due to its excellent performance and great production in the world, especially in China. To access to such high quantities must ensure the requirements of materials such as nutrients for plant growth and take care of the smallest details to make the production cost less, to improve the utilization efficiency, such as nitrogen (N) fertilizer. Hence, N fertilization studies are not only about the dosages, timing and ratio, but also the uptake processes by the plant, N effect on cotton yield and its formation, as well as the movement and metabolism within the plant. As economic and ecological issues are concerned, economizing N fertilization is paid more and more attention. Many approaches have been done and suggested in order to improve NUE like combine the plant sensing techniques and precision application. Simulations and recent field trials demonstrate that site-specific nitrogen management helped reduce technological constraints to higher AE achievement, profit and more sustainable N management. Therefore, improving nitrogen use efficiency (NUE) is one of the key points to ensure cotton production development sustainable. In this review, we try to highlight the accomplishments of N effect on cotton growth and yield, NUE and factors related to NUE in cotton production based on the current knowledge, and from our viewpoint we propose some possible approaches to improve NUE through N managements in terms of application splits, rates, and timing.