Effects of N Application and Planting Density on yield and grain quality of Early Season Rice Ganzhaoxian 52

Results showed that under the local soil and climate,on an average,the rice variety-Ganzaoxian 52 absorbed 158.3 kg/hm2 N fertilizer during its whole growth period with a grain yield of about 6 000 kg/hm2.The highest yield of 6 525 kg/hm2 was obtained with 150 kg/hm2 N fertilizer and planting density of 20.0 cm×16.7 cm.Nitrogen fertilizer and planting density showed a significant interaction on grain yield.Owing to different amount of N fertilizer and different planting density,populations with different quantitative and qualitative characters formed.A population with optimum LAI of 5.9 at booting stage was good for high grain yield and grain quality such as the ratio of head rice,chalky rice percentage and protein content.