Over the last five decades the increase in rice yield has been associated with a dramatic increment in the use of nitrogen (N) fertilizers. Understanding of plant molecular responses to N is critical for our ability to improve the agricultural sustainability of rice cropping systems by developing a comprehensive approach that allows the selection of varieties with enhanced efficiency in their ability to use N and the development of new strategies to better manage N fertilization practices. In order to develop novel tools for real-time assessing of rice N nutritional status, we analyzed the expression profiles of seven putative gene expression markers in the shoots of rice plants grown under different N availability and environmental conditions. Our results suggest that five out of the seven genes analyzed have the potential to be used as agronomic tools to monitor and optimize the N nutritional status of rice
