Transition from a maternal to external nitrogen source in maize seedlings

作     者：Kasra Sabermanesh Luke R. Holtham Jessey George Ute Roessner Berin A. Boughton Sigrid Heuer Mark Tester Darren C. Plett Trevor P. Garnett 

作者机构：Australian Centre for Plant Functional Genomics Waite Research Institute University of Adelaide Adelaide SA 5064 Australia School of Agriculture Food and Wine Waite Research Institute University of Adelaide Adelaide SA 5064 Australia Australian Centre for Plant Functional Genomics School of BioSciences University of Melbourne Parkville Vic. 3010 Australia Metabolomics Australia School of BioSciences University of Melbourne Vic. 3010 Australia King Abdullah University of Science and Technology Center for Desert Agriculture Thuwal 23955-6900 Kingdom of Saudi Arabia6. The Australian Plant Phenomics Facility The Plant Accelerator Waite Campus The University of Adelaide Adelaide SA 5064 Australia The Australian Plant Phenomics Facility The Plant Accelerator Waite Campus The University of Adelaide Adelaide SA 5064 Australia 

出 版 物：《Journal of Integrative Plant Biology》 (植物学报（英文版）)

年 卷 期：2017年第59卷第4期

页      面：261-274页

核心收录：

学科分类：0710[理学-生物学] 09[农学] 0901[农学-作物学] 0703[理学-化学] 0902[农学-园艺学] 

基　　金：Victorian Node of Metabolomics Australia,which is funded through Bioplatforms Australia Pty Ltd,a National Collaborative Research Infrastructure Strategy,5.1 Biomolecular Platforms and informatics investment,and co-investment from the Victorian State Government and The University of Melbourne supported by the Australian Centre for Plant Functional Genomics,the Australian Research Council(LP130101055) Du Pont Pioneer and the Grains Research and Development Corporation(GRS10437) 

主　　题：NRT Transition from a maternal to external nitrogen source in maize seedlings NO 

摘      要：Maximizing NO3 uptake during seedling development is important as it has a major influence on plant growth and yield. However, little is known about the processes leading to, and involved in, the initiation of root NO3 uptake capacity in developing seedlings. This study examines the physiological processes involved in root NO3 uptake and metabolism, to gain an understanding of how the NO3 uptake system responds to meet demand as maize seedlings transition from seed N use to external N capture. The concentrations of seedderived free amino acids within root and shoot tissues are initially high, but decrease rapidly until stabilizing eight days after imbibition （DAI）. Similarly, shoot N% decreases, but does not stabilize until 12-13 DAI. Following the decrease in free amino acid concentrations, root NO3- uptake capacity increases until shoot N% stabilizes. The increase in root NO3 uptake capacity corresponds with a rapid rise in transcript levels of putative NO3 transporters, ZmNRT2.1 and ZmNRT2.2. The processes underlying the increase in root NO3- uptake capacity to meet N demand provide an insight into the processes controlling N uptake.