A New Critical Nitrogen Dilution Curve for Rice Nitrogen Status Diagnosis in Northeast China
A New Critical Nitrogen Dilution Curve for Rice Nitrogen Status Diagnosis in Northeast China作者机构:International Center for Agro-Informatics and Sustainable Development College of Resources and Environmental Sciences China Agricultural University Beijing 100193 (China) Institute of Geography University of Cologne K5ln 50923 (Germany) Precision Agriculture Center Department of Soil Water and Climate University of Minnesota St. Paul 55108 (USA) National Engineering and Technology Center for Information Agriculture Nanjing Agricultural University Nanjing 210095 (China) Qixing Farm Jiansanjiang Jiamusi 156399 (China)
出 版 物:《Pedosphere》 (土壤圈(英文版))
年 卷 期:2018年第28卷第5期
页 面:814-822页
核心收录:
基 金:supported by the Key National Research and Development Program (No. 2016YFD0200602) the National Basic Research Program (No. 2015CB150405) the National Natural Science Foundation (No. 31421092) the SINOGRAIN Project (No. CHN-2152, 14-0039) of China
主 题:japonica rice nitrogen nutrition index nitrogen use efficiency plant nitrogen concentration precision nitrogen mana-gement
摘 要:In-season diagnosis of crop nitrogen(N) status is crucial for precision N management. Critical N(N_c) dilution curve and N nutrition index(NNI) have been proposed as effective methods to diagnose N status of different crops. The N_c dilution curves have been developed for indica rice in the tropical and temperate zones and japonica rice in the subtropical-temperate zone, but they have not been evaluated for short-season japonica rice in Northeast China. The objectives of this study were to evaluate the previously developed N_c dilution curves for rice in Northeast China and to develop a more suitable N_c dilution curve in this region. A total of17 N rate experiments were conducted in Sanjiang Plain, Heilongjiang Province in Northeast China from 2008 to 2013. The results indicated that none of the two previously developed N_c dilution curves was suitable to diagnose N status of the short-season japonica rice in Northeast China. A new N_c dilution curve was developed and can be described by the equation N_c = 27.7 W^(-0.34) if W ≥ 1 Mg dry matter(DM) ha^(-1) or N_c = 27.7 g kg^(-1) DM if W 1 Mg DM ha^(-1), where W is the aboveground biomass. This new curve was lower than the previous curves. It was validated using a separate dataset, and it could discriminate non-N-limiting and N-limiting nutritional conditions. Additional studies are needed to further evaluate it for diagnosing N status of different rice cultivars in Northeast China and develop efficient non-destructive methods to estimate NNI for practical applications.