Root Physiological and Morphological Characteristics of Two Rice Cultivars with Different Nitrogen-Use Efficiency

作     者：FAN Jian-Bo ZHANG Ya-Li D. TURNER DUAN Yin-Hua WANG Dong-Sheng SHEN Qi-Rong FAN Jian-Bo1,2,3, ZHANG Ya-Li1,2, D. TURNER4, DUAN Yin-Hua1,2, WANG Dong-Sheng1,2 and SHEN Qi-Rong1,2,2 1Jiangsu Provincial Key Laboratory for Solid Organic Waste Utilization, Nanjing Agricultural University, Nanjing 210095 (China) 2College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China) 3Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China) 4School of Resource Management, The University of Melbourne, Victoria 3010 (Australia)

作者机构：Jiangsu Provincial Key Laboratory for Solid Organic Waste Utilization Nanjing Agricultural University Nanjing 210095(China) College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 (China) Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) School of Resource Management The University of MelbourneVictoria 3010 (Australia) 

出 版 物：《Pedosphere》 (土壤圈（英文版）)

年 卷 期：2010年第20卷第4期

页      面：446-455页

核心收录：

学科分类：0818[工学-地质资源与地质工程] 09[农学] 0903[农学-农业资源与环境] 0901[农学-作物学] 

基　　金：Supported by the National Key Basic Research Program (973 Program) of China (No.2007CB109304) the NationalNatural Science Foundation of China (Nos.30771290 and 30671234) 

主　　题：N accumulation root bleeding rate root dry weight root surface area total root length 

摘      要：The variation in nitrogen （N） uptake by rice has been widely studied but differences in rice root morphology that may contribute to this variation are not completely understood. Field and greenhouse experiments were carried out to study N accumulation, root dry weights, total root lengths, root surface areas, and root bleeding rates of two rice cultivars, Elio with low N-use efficiency and Nanguang with high N-use efficiency. Low （1 mmol N L^-1） and high （5 mmol N L^-1） N applications were established in the greenhouse experiment, and the N rates were 0, 120, and 240 kg ha^-1 in the field experiments at Jiangning and Jiangpu farms, Nanjing, China. The results showed that the N accumulation, root dry weight, total root length, and root surface area increased with an increase in N application. At the heading stage, N accumulation in the shoots and roots of Nanguang was greater than that of Elio in the field experiments and that of Elio at 5 mmol N L^-1 in the greenhouse experiment. After the heading stage, N accumulation was higher for Nanguang at both 1 and 5 mmol N L^-1 in the greenhouse experiment. The total root length and root surface area were significantly different between the two cultivars. Over the range of the fertilizer application rates, the root lengths of Nanguang at Jiangning Farm were 49%-6170 greater at booting and 26%-39% greater at heading than those of Elio, and at Jiangpu Farm they were 22%-42% and 26%-38% greater, respectively. Nanguang had a greater root bleeding rate than Elio. It was concluded that the N-use efficiency of the two rice cultivars studied depended to a great extent on the root morphological parameters and root physiological characteristics at different growth stages.