Effect of Different Nitrogen Application Rates on the Growth and Nitrogen Uptake of Rice in Chao Lake Basin
[Objective]The optimal nitrogen fertilizer application for rice in the Chao lake basin was studied to providing guidance for improving rice yield and nitrogen utilization efficiency in this region.[Method]The field experiment method was used to analyze the changes in rice growth and nitrogen use efficiency by setting up(N0)no nitrogen fertilizers,apply nitrogen 105 kg/hm2(N1),210 kg/hm2(N2),315 kg/hm2(N3)to four treatments,separately.[Result]The number of effective panicles in rice also showed a pattern of first increasing and then decreasing with the increase of nitrogen application,with N2 being the highest at 196.7×104/hm2;Nitrogen application could significantly increase the number of grains per panicle in rice,but there was no significant difference among different nitrogen application treatments;The relationship between nitrogen application and rice yield follows the law of diminishing returns,showed a parabolic curve with an opening downward.After fitting,when the nitrogen application rate was 202.6 kg/hm2,rice could reach the highest yield,which was 8 732.5 kg/hm2(R2=0.989 2);The nitrogen content in rice grains ranges from 8.91g/kg to 15.01 g/kg,and the nitrogen content in rice grains of each treatment was N3＞N2＞N1＞N0;There was a significant difference in nitrogen uptake by rice grains between different treatments,with N2 being the highest at 132.12 kg/hm2 and N0 being the lowest at 54.81 kg/hm2.The nitrogen uptake by rice grains in each treatment was N2＞N3＞N1＞N0;The nitrogen absorption of straw in each treatment was significantly lower than that of grains,while N2 and N3 treatments were significantly higher than N1 and N0 treatments;The nitrogen recovery rate of N2 was the highest in the current season,at 48.62%,while N1 had the highest nitrogen agronomic utilization rate and nitrogen partial productivity.[Conclusion]In the rice producing areas of the Chao lake basin,when nitrogeh 210 kg/hm2 was used for nitrogen application,the rice yield was higher and the nitrogen utilization efficiency was also higher,making it an appropriate nitrogen application amount.
RiceChao lake basinNitrogen fertilizer dosageNitrogen absorptionNitrogen utilization efficiency
万方数据
维普
