[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.
关键词
水稻/巢湖流域/氮肥用量/氮素吸收/氮素利用效率
Key words
Rice/Chao lake basin/Nitrogen fertilizer dosage/Nitrogen absorption/Nitrogen utilization efficiency
维普
万方数据