Effect of Water and Nitrogen Fertilizer Coupling on the Yield and Panicle Architecture of Japonica Rice in Cold Area

Abstract

This thesis has listed rice as the research object, and by way of water treatment (water-saving treatment and CK treatment) and nitrogen-fertilizer treatment (N0, N1, N2, N3, N4), to analyze the effects of water and nitrogen fertilizer coupling on the yield and panicle architecture of rice. Results show that compared with CK, water-saving irrigation is more effective in promoting the yield. Under N-fertilizer treatment of N1, N2 and N3, the rice yield was increased by more than 10%; while under N0 and N4, the yield difference was not significant. With the increased apply of Nitrogen, under the two watering means, the yield both showed a tendency of firstly increase and later decrease. The yield hit the highest point in water-saving irrigation under N3, followed by water-saving irrigation under N2, and CK under N3.Under N2 and N3, the yield increased in water-saving irrigation was mainly contributed by the increase of the second rachis branches. The yield was increased by 30.69% and 30.37% under N2 and N3 separately. With water-saving irrigation, the yield under N3 is more than that under N2, this is mainly contributed by the increase of the grain number per panicle and the thousand seed weight. Under N3, the yield difference was not significant in either watering treatments, but water-saving irrigation has increased the average value of yield traits. Analysis of the panicle architecture has revealed that compared with CK, water-saving irrigation is more effective in increase the rice yield, which was mainly realized by the significant increase in the number of second rachis branches.