Four different cultivations were compared relative to their effects on the ratios of total nitrogen, protein nitrogen, protein yield, and the activities of key enzymes of nitrogen metabolism in brown rice Xianzaoxian29. By filed experiments, the "Improved synthesized cultivation I" obtained the highest ratios of total nitrogen, the protein nitrogen and the protein yield in brown rice, showing an increase of 17.86%, 17.96% and 46.55%, respectively, compared with the "Conventional cultivation" . Furthermore, it improved activi...