Effects of nitrogen fertilizer management on nitrogen contents in different forms in rice plants.

A pot experiment was done to study the contents of different nitrogen forms,such as total nitrogen,protein nitrogen,chlorophyll nitrogen,soluble protein nitrogen,Rubisco nitrogen,free amino acid nitrogen in rice plants and their responses to nitrogen fertilizer management with rice varieties Guichao 2 and Diejiazhan as test materials. The contents of the above-mentioned nitrogen forms showed the same tendency to nitrogen fertilizer management,which increased with increasing nitrogen levels or more fertilizer applied at the heading and maturity stage under the same nitrogen level. However,the increase of different nitrogen forms varied. Significantly influenced by nitrogen fertilizer management,the contents of Rubisco-N and free amino acid-N in rice plant at the heading and maturity stage were significantly different under different nitrogen fertilization patterns. Correlation analysis indicated that there were significantly positive correlations between the total nitrogen content and protein nitrogen content in rice plants at the heading and maturity stage in early and late seasons.